diff options
Diffstat (limited to 'Documentation')
44 files changed, 1802 insertions, 1480 deletions
diff --git a/Documentation/ABI/testing/debugfs-olpc b/Documentation/ABI/testing/debugfs-olpc new file mode 100644 index 0000000..bd76cc6 --- /dev/null +++ b/Documentation/ABI/testing/debugfs-olpc @@ -0,0 +1,16 @@ +What: /sys/kernel/debug/olpc-ec/cmd +Date: Dec 2011 +KernelVersion: 3.4 +Contact: devel@lists.laptop.org +Description: + +A generic interface for executing OLPC Embedded Controller commands and +reading their responses. + +To execute a command, write data with the format: CC:N A A A A +CC is the (hex) command, N is the count of expected reply bytes, and A A A A +are optional (hex) arguments. + +To read the response (if any), read from the generic node after executing +a command. Hex reply bytes will be returned, *whether or not* they came from +the immediately previous command. diff --git a/Documentation/ABI/testing/sysfs-block-dm b/Documentation/ABI/testing/sysfs-block-dm new file mode 100644 index 0000000..87ca569 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-block-dm @@ -0,0 +1,25 @@ +What: /sys/block/dm-<num>/dm/name +Date: January 2009 +KernelVersion: 2.6.29 +Contact: dm-devel@redhat.com +Description: Device-mapper device name. + Read-only string containing mapped device name. +Users: util-linux, device-mapper udev rules + +What: /sys/block/dm-<num>/dm/uuid +Date: January 2009 +KernelVersion: 2.6.29 +Contact: dm-devel@redhat.com +Description: Device-mapper device UUID. + Read-only string containing DM-UUID or empty string + if DM-UUID is not set. +Users: util-linux, device-mapper udev rules + +What: /sys/block/dm-<num>/dm/suspended +Date: June 2009 +KernelVersion: 2.6.31 +Contact: dm-devel@redhat.com +Description: Device-mapper device suspend state. + Contains the value 1 while the device is suspended. + Otherwise it contains 0. Read-only attribute. +Users: util-linux, device-mapper udev rules diff --git a/Documentation/ABI/testing/sysfs-driver-samsung-laptop b/Documentation/ABI/testing/sysfs-driver-samsung-laptop index e82e7c2..678819a 100644 --- a/Documentation/ABI/testing/sysfs-driver-samsung-laptop +++ b/Documentation/ABI/testing/sysfs-driver-samsung-laptop @@ -17,3 +17,21 @@ Description: Some Samsung laptops have different "performance levels" Specifically, not all support the "overclock" option, and it's still unknown if this value even changes anything, other than making the user feel a bit better. + +What: /sys/devices/platform/samsung/battery_life_extender +Date: December 1, 2011 +KernelVersion: 3.3 +Contact: Corentin Chary <corentin.chary@gmail.com> +Description: Max battery charge level can be modified, battery cycle + life can be extended by reducing the max battery charge + level. + 0 means normal battery mode (100% charge) + 1 means battery life extender mode (80% charge) + +What: /sys/devices/platform/samsung/usb_charge +Date: December 1, 2011 +KernelVersion: 3.3 +Contact: Corentin Chary <corentin.chary@gmail.com> +Description: Use your USB ports to charge devices, even + when your laptop is powered off. + 1 means enabled, 0 means disabled. diff --git a/Documentation/Makefile b/Documentation/Makefile index 9b4bc5c..30b656e 100644 --- a/Documentation/Makefile +++ b/Documentation/Makefile @@ -1,3 +1,3 @@ obj-m := DocBook/ accounting/ auxdisplay/ connector/ \ filesystems/ filesystems/configfs/ ia64/ laptops/ networking/ \ - pcmcia/ spi/ timers/ vm/ watchdog/src/ + pcmcia/ spi/ timers/ watchdog/src/ diff --git a/Documentation/clk.txt b/Documentation/clk.txt new file mode 100644 index 0000000..1943fae --- /dev/null +++ b/Documentation/clk.txt @@ -0,0 +1,233 @@ + The Common Clk Framework + Mike Turquette <mturquette@ti.com> + +This document endeavours to explain the common clk framework details, +and how to port a platform over to this framework. It is not yet a +detailed explanation of the clock api in include/linux/clk.h, but +perhaps someday it will include that information. + + Part 1 - introduction and interface split + +The common clk framework is an interface to control the clock nodes +available on various devices today. This may come in the form of clock +gating, rate adjustment, muxing or other operations. This framework is +enabled with the CONFIG_COMMON_CLK option. + +The interface itself is divided into two halves, each shielded from the +details of its counterpart. First is the common definition of struct +clk which unifies the framework-level accounting and infrastructure that +has traditionally been duplicated across a variety of platforms. Second +is a common implementation of the clk.h api, defined in +drivers/clk/clk.c. Finally there is struct clk_ops, whose operations +are invoked by the clk api implementation. + +The second half of the interface is comprised of the hardware-specific +callbacks registered with struct clk_ops and the corresponding +hardware-specific structures needed to model a particular clock. For +the remainder of this document any reference to a callback in struct +clk_ops, such as .enable or .set_rate, implies the hardware-specific +implementation of that code. Likewise, references to struct clk_foo +serve as a convenient shorthand for the implementation of the +hardware-specific bits for the hypothetical "foo" hardware. + +Tying the two halves of this interface together is struct clk_hw, which +is defined in struct clk_foo and pointed to within struct clk. This +allows easy for navigation between the two discrete halves of the common +clock interface. + + Part 2 - common data structures and api + +Below is the common struct clk definition from +include/linux/clk-private.h, modified for brevity: + + struct clk { + const char *name; + const struct clk_ops *ops; + struct clk_hw *hw; + char **parent_names; + struct clk **parents; + struct clk *parent; + struct hlist_head children; + struct hlist_node child_node; + ... + }; + +The members above make up the core of the clk tree topology. The clk +api itself defines several driver-facing functions which operate on +struct clk. That api is documented in include/linux/clk.h. + +Platforms and devices utilizing the common struct clk use the struct +clk_ops pointer in struct clk to perform the hardware-specific parts of +the operations defined in clk.h: + + struct clk_ops { + int (*prepare)(struct clk_hw *hw); + void (*unprepare)(struct clk_hw *hw); + int (*enable)(struct clk_hw *hw); + void (*disable)(struct clk_hw *hw); + int (*is_enabled)(struct clk_hw *hw); + unsigned long (*recalc_rate)(struct clk_hw *hw, + unsigned long parent_rate); + long (*round_rate)(struct clk_hw *hw, unsigned long, + unsigned long *); + int (*set_parent)(struct clk_hw *hw, u8 index); + u8 (*get_parent)(struct clk_hw *hw); + int (*set_rate)(struct clk_hw *hw, unsigned long); + void (*init)(struct clk_hw *hw); + }; + + Part 3 - hardware clk implementations + +The strength of the common struct clk comes from its .ops and .hw pointers +which abstract the details of struct clk from the hardware-specific bits, and +vice versa. To illustrate consider the simple gateable clk implementation in +drivers/clk/clk-gate.c: + +struct clk_gate { + struct clk_hw hw; + void __iomem *reg; + u8 bit_idx; + ... +}; + +struct clk_gate contains struct clk_hw hw as well as hardware-specific +knowledge about which register and bit controls this clk's gating. +Nothing about clock topology or accounting, such as enable_count or +notifier_count, is needed here. That is all handled by the common +framework code and struct clk. + +Let's walk through enabling this clk from driver code: + + struct clk *clk; + clk = clk_get(NULL, "my_gateable_clk"); + + clk_prepare(clk); + clk_enable(clk); + +The call graph for clk_enable is very simple: + +clk_enable(clk); + clk->ops->enable(clk->hw); + [resolves to...] + clk_gate_enable(hw); + [resolves struct clk gate with to_clk_gate(hw)] + clk_gate_set_bit(gate); + +And the definition of clk_gate_set_bit: + +static void clk_gate_set_bit(struct clk_gate *gate) +{ + u32 reg; + + reg = __raw_readl(gate->reg); + reg |= BIT(gate->bit_idx); + writel(reg, gate->reg); +} + +Note that to_clk_gate is defined as: + +#define to_clk_gate(_hw) container_of(_hw, struct clk_gate, clk) + +This pattern of abstraction is used for every clock hardware +representation. + + Part 4 - supporting your own clk hardware + +When implementing support for a new type of clock it only necessary to +include the following header: + +#include <linux/clk-provider.h> + +include/linux/clk.h is included within that header and clk-private.h +must never be included from the code which implements the operations for +a clock. More on that below in Part 5. + +To construct a clk hardware structure for your platform you must define +the following: + +struct clk_foo { + struct clk_hw hw; + ... hardware specific data goes here ... +}; + +To take advantage of your data you'll need to support valid operations +for your clk: + +struct clk_ops clk_foo_ops { + .enable = &clk_foo_enable; + .disable = &clk_foo_disable; +}; + +Implement the above functions using container_of: + +#define to_clk_foo(_hw) container_of(_hw, struct clk_foo, hw) + +int clk_foo_enable(struct clk_hw *hw) +{ + struct clk_foo *foo; + + foo = to_clk_foo(hw); + + ... perform magic on foo ... + + return 0; +}; + +Below is a matrix detailing which clk_ops are mandatory based upon the +hardware capbilities of that clock. A cell marked as "y" means +mandatory, a cell marked as "n" implies that either including that +callback is invalid or otherwise uneccesary. Empty cells are either +optional or must be evaluated on a case-by-case basis. + + clock hardware characteristics + ----------------------------------------------------------- + | gate | change rate | single parent | multiplexer | root | + |------|-------------|---------------|-------------|------| +.prepare | | | | | | +.unprepare | | | | | | + | | | | | | +.enable | y | | | | | +.disable | y | | | | | +.is_enabled | y | | | | | + | | | | | | +.recalc_rate | | y | | | | +.round_rate | | y | | | | +.set_rate | | y | | | | + | | | | | | +.set_parent | | | n | y | n | +.get_parent | | | n | y | n | + | | | | | | +.init | | | | | | + ----------------------------------------------------------- + +Finally, register your clock at run-time with a hardware-specific +registration function. This function simply populates struct clk_foo's +data and then passes the common struct clk parameters to the framework +with a call to: + +clk_register(...) + +See the basic clock types in drivers/clk/clk-*.c for examples. + + Part 5 - static initialization of clock data + +For platforms with many clocks (often numbering into the hundreds) it +may be desirable to statically initialize some clock data. This +presents a problem since the definition of struct clk should be hidden +from everyone except for the clock core in drivers/clk/clk.c. + +To get around this problem struct clk's definition is exposed in +include/linux/clk-private.h along with some macros for more easily +initializing instances of the basic clock types. These clocks must +still be initialized with the common clock framework via a call to +__clk_init. + +clk-private.h must NEVER be included by code which implements struct +clk_ops callbacks, nor must it be included by any logic which pokes +around inside of struct clk at run-time. To do so is a layering +violation. + +To better enforce this policy, always follow this simple rule: any +statically initialized clock data MUST be defined in a separate file +from the logic that implements its ops. Basically separate the logic +from the data and all is well. diff --git a/Documentation/device-mapper/thin-provisioning.txt b/Documentation/device-mapper/thin-provisioning.txt index 1ff044d..3370bc4 100644 --- a/Documentation/device-mapper/thin-provisioning.txt +++ b/Documentation/device-mapper/thin-provisioning.txt @@ -75,10 +75,12 @@ less sharing than average you'll need a larger-than-average metadata device. As a guide, we suggest you calculate the number of bytes to use in the metadata device as 48 * $data_dev_size / $data_block_size but round it up -to 2MB if the answer is smaller. The largest size supported is 16GB. +to 2MB if the answer is smaller. If you're creating large numbers of +snapshots which are recording large amounts of change, you may find you +need to increase this. -If you're creating large numbers of snapshots which are recording large -amounts of change, you may need find you need to increase this. +The largest size supported is 16GB: If the device is larger, +a warning will be issued and the excess space will not be used. Reloading a pool table ---------------------- @@ -167,6 +169,38 @@ ii) Using an internal snapshot. dmsetup create snap --table "0 2097152 thin /dev/mapper/pool 1" +External snapshots +------------------ + +You can use an external _read only_ device as an origin for a +thinly-provisioned volume. Any read to an unprovisioned area of the +thin device will be passed through to the origin. Writes trigger +the allocation of new blocks as usual. + +One use case for this is VM hosts that want to run guests on +thinly-provisioned volumes but have the base image on another device +(possibly shared between many VMs). + +You must not write to the origin device if you use this technique! +Of course, you may write to the thin device and take internal snapshots +of the thin volume. + +i) Creating a snapshot of an external device + + This is the same as creating a thin device. + You don't mention the origin at this stage. + + dmsetup message /dev/mapper/pool 0 "create_thin 0" + +ii) Using a snapshot of an external device. + + Append an extra parameter to the thin target specifying the origin: + + dmsetup create snap --table "0 2097152 thin /dev/mapper/pool 0 /dev/image" + + N.B. All descendants (internal snapshots) of this snapshot require the + same extra origin parameter. + Deactivation ------------ @@ -189,7 +223,13 @@ i) Constructor <low water mark (blocks)> [<number of feature args> [<arg>]*] Optional feature arguments: - - 'skip_block_zeroing': skips the zeroing of newly-provisioned blocks. + + skip_block_zeroing: Skip the zeroing of newly-provisioned blocks. + + ignore_discard: Disable discard support. + + no_discard_passdown: Don't pass discards down to the underlying + data device, but just remove the mapping. Data block size must be between 64KB (128 sectors) and 1GB (2097152 sectors) inclusive. @@ -237,16 +277,6 @@ iii) Messages Deletes a thin device. Irreversible. - trim <dev id> <new size in sectors> - - Delete mappings from the end of a thin device. Irreversible. - You might want to use this if you're reducing the size of - your thinly-provisioned device. In many cases, due to the - sharing of blocks between devices, it is not possible to - determine in advance how much space 'trim' will release. (In - future a userspace tool might be able to perform this - calculation.) - set_transaction_id <current id> <new id> Userland volume managers, such as LVM, need a way to @@ -262,7 +292,7 @@ iii) Messages i) Constructor - thin <pool dev> <dev id> + thin <pool dev> <dev id> [<external origin dev>] pool dev: the thin-pool device, e.g. /dev/mapper/my_pool or 253:0 @@ -271,6 +301,11 @@ i) Constructor the internal device identifier of the device to be activated. + external origin dev: + an optional block device outside the pool to be treated as a + read-only snapshot origin: reads to unprovisioned areas of the + thin target will be mapped to this device. + The pool doesn't store any size against the thin devices. If you load a thin target that is smaller than you've been using previously, then you'll have no access to blocks mapped beyond the end. If you diff --git a/Documentation/device-mapper/verity.txt b/Documentation/device-mapper/verity.txt new file mode 100644 index 0000000..32e4879 --- /dev/null +++ b/Documentation/device-mapper/verity.txt @@ -0,0 +1,194 @@ +dm-verity +========== + +Device-Mapper's "verity" target provides transparent integrity checking of +block devices using a cryptographic digest provided by the kernel crypto API. +This target is read-only. + +Construction Parameters +======================= + <version> <dev> <hash_dev> <hash_start> + <data_block_size> <hash_block_size> + <num_data_blocks> <hash_start_block> + <algorithm> <digest> <salt> + +<version> + This is the version number of the on-disk format. + + 0 is the original format used in the Chromium OS. + The salt is appended when hashing, digests are stored continuously and + the rest of the block is padded with zeros. + + 1 is the current format that should be used for new devices. + The salt is prepended when hashing and each digest is + padded with zeros to the power of two. + +<dev> + This is the device containing the data the integrity of which needs to be + checked. It may be specified as a path, like /dev/sdaX, or a device number, + <major>:<minor>. + +<hash_dev> + This is the device that that supplies the hash tree data. It may be + specified similarly to the device path and may be the same device. If the + same device is used, the hash_start should be outside of the dm-verity + configured device size. + +<data_block_size> + The block size on a data device. Each block corresponds to one digest on + the hash device. + +<hash_block_size> + The size of a hash block. + +<num_data_blocks> + The number of data blocks on the data device. Additional blocks are + inaccessible. You can place hashes to the same partition as data, in this + case hashes are placed after <num_data_blocks>. + +<hash_start_block> + This is the offset, in <hash_block_size>-blocks, from the start of hash_dev + to the root block of the hash tree. + +<algorithm> + The cryptographic hash algorithm used for this device. This should + be the name of the algorithm, like "sha1". + +<digest> + The hexadecimal encoding of the cryptographic hash of the root hash block + and the salt. This hash should be trusted as there is no other authenticity + beyond this point. + +<salt> + The hexadecimal encoding of the salt value. + +Theory of operation +=================== + +dm-verity is meant to be setup as part of a verified boot path. This +may be anything ranging from a boot using tboot or trustedgrub to just +booting from a known-good device (like a USB drive or CD). + +When a dm-verity device is configured, it is expected that the caller +has been authenticated in some way (cryptographic signatures, etc). +After instantiation, all hashes will be verified on-demand during +disk access. If they cannot be verified up to the root node of the +tree, the root hash, then the I/O will fail. This should identify +tampering with any data on the device and the hash data. + +Cryptographic hashes are used to assert the integrity of the device on a +per-block basis. This allows for a lightweight hash computation on first read +into the page cache. Block hashes are stored linearly-aligned to the nearest +block the size of a page. + +Hash Tree +--------- + +Each node in the tree is a cryptographic hash. If it is a leaf node, the hash +is of some block data on disk. If it is an intermediary node, then the hash is +of a number of child nodes. + +Each entry in the tree is a collection of neighboring nodes that fit in one +block. The number is determined based on block_size and the size of the +selected cryptographic digest algorithm. The hashes are linearly-ordered in +this entry and any unaligned trailing space is ignored but included when +calculating the parent node. + +The tree looks something like: + +alg = sha256, num_blocks = 32768, block_size = 4096 + + [ root ] + / . . . \ + [entry_0] [entry_1] + / . . . \ . . . \ + [entry_0_0] . . . [entry_0_127] . . . . [entry_1_127] + / ... \ / . . . \ / \ + blk_0 ... blk_127 blk_16256 blk_16383 blk_32640 . . . blk_32767 + + +On-disk format +============== + +Below is the recommended on-disk format. The verity kernel code does not +read the on-disk header. It only reads the hash blocks which directly +follow the header. It is expected that a user-space tool will verify the +integrity of the verity_header and then call dmsetup with the correct +parameters. Alternatively, the header can be omitted and the dmsetup +parameters can be passed via the kernel command-line in a rooted chain +of trust where the command-line is verified. + +The on-disk format is especially useful in cases where the hash blocks +are on a separate partition. The magic number allows easy identification +of the partition contents. Alternatively, the hash blocks can be stored +in the same partition as the data to be verified. In such a configuration +the filesystem on the partition would be sized a little smaller than +the full-partition, leaving room for the hash blocks. + +struct superblock { + uint8_t signature[8] + "verity\0\0"; + + uint8_t version; + 1 - current format + + uint8_t data_block_bits; + log2(data block size) + + uint8_t hash_block_bits; + log2(hash block size) + + uint8_t pad1[1]; + zero padding + + uint16_t salt_size; + big-endian salt size + + uint8_t pad2[2]; + zero padding + + uint32_t data_blocks_hi; + big-endian high 32 bits of the 64-bit number of data blocks + + uint32_t data_blocks_lo; + big-endian low 32 bits of the 64-bit number of data blocks + + uint8_t algorithm[16]; + cryptographic algorithm + + uint8_t salt[384]; + salt (the salt size is specified above) + + uint8_t pad3[88]; + zero padding to 512-byte boundary +} + +Directly following the header (and with sector number padded to the next hash +block boundary) are the hash blocks which are stored a depth at a time +(starting from the root), sorted in order of increasing index. + +Status +====== +V (for Valid) is returned if every check performed so far was valid. +If any check failed, C (for Corruption) is returned. + +Example +======= + +Setup a device: + dmsetup create vroot --table \ + "0 2097152 "\ + "verity 1 /dev/sda1 /dev/sda2 4096 4096 2097152 1 "\ + "4392712ba01368efdf14b05c76f9e4df0d53664630b5d48632ed17a137f39076 "\ + "1234000000000000000000000000000000000000000000000000000000000000" + +A command line tool veritysetup is available to compute or verify +the hash tree or activate the kernel driver. This is available from +the LVM2 upstream repository and may be supplied as a package called +device-mapper-verity-tools: + git://sources.redhat.com/git/lvm2 + http://sourceware.org/git/?p=lvm2.git + http://sourceware.org/cgi-bin/cvsweb.cgi/LVM2/verity?cvsroot=lvm2 + +veritysetup -a vroot /dev/sda1 /dev/sda2 \ + 4392712ba01368efdf14b05c76f9e4df0d53664630b5d48632ed17a137f39076 diff --git a/Documentation/devicetree/bindings/arm/atmel-at91.txt b/Documentation/devicetree/bindings/arm/atmel-at91.txt index 1aeaf6f..ecc81e3 100644 --- a/Documentation/devicetree/bindings/arm/atmel-at91.txt +++ b/Documentation/devicetree/bindings/arm/atmel-at91.txt @@ -30,3 +30,63 @@ One interrupt per TC channel in a TC block: reg = <0xfffdc000 0x100>; interrupts = <26 4 27 4 28 4>; }; + +RSTC Reset Controller required properties: +- compatible: Should be "atmel,<chip>-rstc". + <chip> can be "at91sam9260" or "at91sam9g45" +- reg: Should contain registers location and length + +Example: + + rstc@fffffd00 { + compatible = "atmel,at91sam9260-rstc"; + reg = <0xfffffd00 0x10>; + }; + +RAMC SDRAM/DDR Controller required properties: +- compatible: Should be "atmel,at91sam9260-sdramc", + "atmel,at91sam9g45-ddramc", +- reg: Should contain registers location and length + For at91sam9263 and at91sam9g45 you must specify 2 entries. + +Examples: + + ramc0: ramc@ffffe800 { + compatible = "atmel,at91sam9g45-ddramc"; + reg = <0xffffe800 0x200>; + }; + + ramc0: ramc@ffffe400 { + compatible = "atmel,at91sam9g45-ddramc"; + reg = <0xffffe400 0x200 + 0xffffe600 0x200>; + }; + +SHDWC Shutdown Controller + +required properties: +- compatible: Should be "atmel,<chip>-shdwc". + <chip> can be "at91sam9260", "at91sam9rl" or "at91sam9x5". +- reg: Should contain registers location and length + +optional properties: +- atmel,wakeup-mode: String, operation mode of the wakeup mode. + Supported values are: "none", "high", "low", "any". +- atmel,wakeup-counter: Counter on Wake-up 0 (between 0x0 and 0xf). + +optional at91sam9260 properties: +- atmel,wakeup-rtt-timer: boolean to enable Real-time Timer Wake-up. + +optional at91sam9rl properties: +- atmel,wakeup-rtc-timer: boolean to enable Real-time Clock Wake-up. +- atmel,wakeup-rtt-timer: boolean to enable Real-time Timer Wake-up. + +optional at91sam9x5 properties: +- atmel,wakeup-rtc-timer: boolean to enable Real-time Clock Wake-up. + +Example: + + rstc@fffffd00 { + compatible = "atmel,at91sam9260-rstc"; + reg = <0xfffffd00 0x10>; + }; diff --git a/Documentation/devicetree/bindings/arm/atmel-pmc.txt b/Documentation/devicetree/bindings/arm/atmel-pmc.txt new file mode 100644 index 0000000..389bed5 --- /dev/null +++ b/Documentation/devicetree/bindings/arm/atmel-pmc.txt @@ -0,0 +1,11 @@ +* Power Management Controller (PMC) + +Required properties: +- compatible: Should be "atmel,at91rm9200-pmc" +- reg: Should contain PMC registers location and length + +Examples: + pmc: pmc@fffffc00 { + compatible = "atmel,at91rm9200-pmc"; + reg = <0xfffffc00 0x100>; + }; diff --git a/Documentation/devicetree/bindings/arm/spear.txt b/Documentation/devicetree/bindings/arm/spear.txt new file mode 100644 index 0000000..f8e54f0 --- /dev/null +++ b/Documentation/devicetree/bindings/arm/spear.txt @@ -0,0 +1,8 @@ +ST SPEAr Platforms Device Tree Bindings +--------------------------------------- + +Boards with the ST SPEAr600 SoC shall have the following properties: + +Required root node property: + +compatible = "st,spear600"; diff --git a/Documentation/devicetree/bindings/gpio/gpio-omap.txt b/Documentation/devicetree/bindings/gpio/gpio-omap.txt new file mode 100644 index 0000000..bff51a2 --- /dev/null +++ b/Documentation/devicetree/bindings/gpio/gpio-omap.txt @@ -0,0 +1,36 @@ +OMAP GPIO controller bindings + +Required properties: +- compatible: + - "ti,omap2-gpio" for OMAP2 controllers + - "ti,omap3-gpio" for OMAP3 controllers + - "ti,omap4-gpio" for OMAP4 controllers +- #gpio-cells : Should be two. + - first cell is the pin number + - second cell is used to specify optional parameters (unused) +- gpio-controller : Marks the device node as a GPIO controller. +- #interrupt-cells : Should be 2. +- interrupt-controller: Mark the device node as an interrupt controller + The first cell is the GPIO number. + The second cell is used to specify flags: + bits[3:0] trigger type and level flags: + 1 = low-to-high edge triggered. + 2 = high-to-low edge triggered. + 4 = active high level-sensitive. + 8 = active low level-sensitive. + +OMAP specific properties: +- ti,hwmods: Name of the hwmod associated to the GPIO: + "gpio<X>", <X> being the 1-based instance number from the HW spec + + +Example: + +gpio4: gpio4 { + compatible = "ti,omap4-gpio"; + ti,hwmods = "gpio4"; + #gpio-cells = <2>; + gpio-controller; + #interrupt-cells = <2>; + interrupt-controller; +}; diff --git a/Documentation/devicetree/bindings/gpio/gpio-twl4030.txt b/Documentation/devicetree/bindings/gpio/gpio-twl4030.txt new file mode 100644 index 0000000..16695d9 --- /dev/null +++ b/Documentation/devicetree/bindings/gpio/gpio-twl4030.txt @@ -0,0 +1,23 @@ +twl4030 GPIO controller bindings + +Required properties: +- compatible: + - "ti,twl4030-gpio" for twl4030 GPIO controller +- #gpio-cells : Should be two. + - first cell is the pin number + - second cell is used to specify optional parameters (unused) +- gpio-controller : Marks the device node as a GPIO controller. +- #interrupt-cells : Should be 2. +- interrupt-controller: Mark the device node as an interrupt controller + The first cell is the GPIO number. + The second cell is not used. + +Example: + +twl_gpio: gpio { + compatible = "ti,twl4030-gpio"; + #gpio-cells = <2>; + gpio-controller; + #interrupt-cells = <2>; + interrupt-controller; +}; diff --git a/Documentation/devicetree/bindings/gpio/gpio_i2c.txt b/Documentation/devicetree/bindings/gpio/gpio_i2c.txt new file mode 100644 index 0000000..4f8ec94 --- /dev/null +++ b/Documentation/devicetree/bindings/gpio/gpio_i2c.txt @@ -0,0 +1,32 @@ +Device-Tree bindings for i2c gpio driver + +Required properties: + - compatible = "i2c-gpio"; + - gpios: sda and scl gpio + + +Optional properties: + - i2c-gpio,sda-open-drain: sda as open drain + - i2c-gpio,scl-open-drain: scl as open drain + - i2c-gpio,scl-output-only: scl as output only + - i2c-gpio,delay-us: delay between GPIO operations (may depend on each platform) + - i2c-gpio,timeout-ms: timeout to get data + +Example nodes: + +i2c@0 { + compatible = "i2c-gpio"; + gpios = <&pioA 23 0 /* sda */ + &pioA 24 0 /* scl */ + >; + i2c-gpio,sda-open-drain; + i2c-gpio,scl-open-drain; + i2c-gpio,delay-us = <2>; /* ~100 kHz */ + #address-cells = <1>; + #size-cells = <0>; + + rv3029c2@56 { + compatible = "rv3029c2"; + reg = <0x56>; + }; +}; diff --git a/Documentation/devicetree/bindings/gpio/sodaville.txt b/Documentation/devicetree/bindings/gpio/sodaville.txt new file mode 100644 index 0000000..563eff2 --- /dev/null +++ b/Documentation/devicetree/bindings/gpio/sodaville.txt @@ -0,0 +1,48 @@ +GPIO controller on CE4100 / Sodaville SoCs +========================================== + +The bindings for CE4100's GPIO controller match the generic description +which is covered by the gpio.txt file in this folder. + +The only additional property is the intel,muxctl property which holds the +value which is written into the MUXCNTL register. + +There is no compatible property for now because the driver is probed via +PCI id (vendor 0x8086 device 0x2e67). + +The interrupt specifier consists of two cells encoded as follows: + - <1st cell>: The interrupt-number that identifies the interrupt source. + - <2nd cell>: The level-sense information, encoded as follows: + 4 - active high level-sensitive + 8 - active low level-sensitive + +Example of the GPIO device and one user: + + pcigpio: gpio@b,1 { + /* two cells for GPIO and interrupt */ + #gpio-cells = <2>; + #interrupt-cells = <2>; + compatible = "pci8086,2e67.2", + "pci8086,2e67", + "pciclassff0000", + "pciclassff00"; + + reg = <0x15900 0x0 0x0 0x0 0x0>; + /* Interrupt line of the gpio device */ + interrupts = <15 1>; + /* It is an interrupt and GPIO controller itself */ + interrupt-controller; + gpio-controller; + intel,muxctl = <0>; + }; + + testuser@20 { + compatible = "example,testuser"; + /* User the 11th GPIO line as an active high triggered + * level interrupt + */ + interrupts = <11 8>; + interrupt-parent = <&pcigpio>; + /* Use this GPIO also with the gpio functions */ + gpios = <&pcigpio 11 0>; + }; diff --git a/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt b/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt new file mode 100644 index 0000000..dbd4368 --- /dev/null +++ b/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt @@ -0,0 +1,33 @@ +* TI Highspeed MMC host controller for OMAP + +The Highspeed MMC Host Controller on TI OMAP family +provides an interface for MMC, SD, and SDIO types of memory cards. + +Required properties: +- compatible: + Should be "ti,omap2-hsmmc", for OMAP2 controllers + Should be "ti,omap3-hsmmc", for OMAP3 controllers + Should be "ti,omap4-hsmmc", for OMAP4 controllers +- ti,hwmods: Must be "mmc<n>", n is controller instance starting 1 +- reg : should contain hsmmc registers location and length + +Optional properties: +ti,dual-volt: boolean, supports dual voltage cards +<supply-name>-supply: phandle to the regulator device tree node +"supply-name" examples are "vmmc", "vmmc_aux" etc +ti,bus-width: Number of data lines, default assumed is 1 if the property is missing. +cd-gpios: GPIOs for card detection +wp-gpios: GPIOs for write protection +ti,non-removable: non-removable slot (like eMMC) +ti,needs-special-reset: Requires a special softreset sequence + +Example: + mmc1: mmc@0x4809c000 { + compatible = "ti,omap4-hsmmc"; + reg = <0x4809c000 0x400>; + ti,hwmods = "mmc1"; + ti,dual-volt; + ti,bus-width = <4>; + vmmc-supply = <&vmmc>; /* phandle to regulator node */ + ti,non-removable; + }; diff --git a/Documentation/devicetree/bindings/mtd/arm-versatile.txt b/Documentation/devicetree/bindings/mtd/arm-versatile.txt index 476845d..beace4b 100644 --- a/Documentation/devicetree/bindings/mtd/arm-versatile.txt +++ b/Documentation/devicetree/bindings/mtd/arm-versatile.txt @@ -4,5 +4,5 @@ Required properties: - compatible : must be "arm,versatile-flash"; - bank-width : width in bytes of flash interface. -Optional properties: -- Subnode partition map from mtd flash binding +The device tree may optionally contain sub-nodes describing partitions of the +address space. See partition.txt for more detail. diff --git a/Documentation/devicetree/bindings/mtd/atmel-dataflash.txt b/Documentation/devicetree/bindings/mtd/atmel-dataflash.txt index ef66ddd..1889a4d 100644 --- a/Documentation/devicetree/bindings/mtd/atmel-dataflash.txt +++ b/Documentation/devicetree/bindings/mtd/atmel-dataflash.txt @@ -3,6 +3,9 @@ Required properties: - compatible : "atmel,<model>", "atmel,<series>", "atmel,dataflash". +The device tree may optionally contain sub-nodes describing partitions of the +address space. See partition.txt for more detail. + Example: flash@1 { diff --git a/Documentation/devicetree/bindings/mtd/atmel-nand.txt b/Documentation/devicetree/bindings/mtd/atmel-nand.txt new file mode 100644 index 0000000..5903ecf --- /dev/null +++ b/Documentation/devicetree/bindings/mtd/atmel-nand.txt @@ -0,0 +1,41 @@ +Atmel NAND flash + +Required properties: +- compatible : "atmel,at91rm9200-nand". +- reg : should specify localbus address and size used for the chip, + and if availlable the ECC. +- atmel,nand-addr-offset : offset for the address latch. +- atmel,nand-cmd-offset : offset for the command latch. +- #address-cells, #size-cells : Must be present if the device has sub-nodes + representing partitions. + +- gpios : specifies the gpio pins to control the NAND device. detect is an + optional gpio and may be set to 0 if not present. + +Optional properties: +- nand-ecc-mode : String, operation mode of the NAND ecc mode, soft by default. + Supported values are: "none", "soft", "hw", "hw_syndrome", "hw_oob_first", + "soft_bch". +- nand-bus-width : 8 or 16 bus width if not present 8 +- nand-on-flash-bbt: boolean to enable on flash bbt option if not present false + +Examples: +nand0: nand@40000000,0 { + compatible = "atmel,at91rm9200-nand"; + #address-cells = <1>; + #size-cells = <1>; + reg = <0x40000000 0x10000000 + 0xffffe800 0x200 + >; + atmel,nand-addr-offset = <21>; + atmel,nand-cmd-offset = <22>; + nand-on-flash-bbt; + nand-ecc-mode = "soft"; + gpios = <&pioC 13 0 + &pioC 14 0 + 0 + >; + partition@0 { + ... + }; +}; diff --git a/Documentation/devicetree/bindings/mtd/fsl-upm-nand.txt b/Documentation/devicetree/bindings/mtd/fsl-upm-nand.txt index 00f1f54..fce4894 100644 --- a/Documentation/devicetree/bindings/mtd/fsl-upm-nand.txt +++ b/Documentation/devicetree/bindings/mtd/fsl-upm-nand.txt @@ -19,6 +19,10 @@ Optional properties: read registers (tR). Required if property "gpios" is not used (R/B# pins not connected). +Each flash chip described may optionally contain additional sub-nodes +describing partitions of the address space. See partition.txt for more +detail. + Examples: upm@1,0 { diff --git a/Documentation/devicetree/bindings/mtd/gpio-control-nand.txt b/Documentation/devicetree/bindings/mtd/gpio-control-nand.txt index 719f4dc..36ef07d 100644 --- a/Documentation/devicetree/bindings/mtd/gpio-control-nand.txt +++ b/Documentation/devicetree/bindings/mtd/gpio-control-nand.txt @@ -25,6 +25,9 @@ Optional properties: GPIO state and before and after command byte writes, this register will be read to ensure that the GPIO accesses have completed. +The device tree may optionally contain sub-nodes describing partitions of the +address space. See partition.txt for more detail. + Examples: gpio-nand@1,0 { diff --git a/Documentation/devicetree/bindings/mtd/mtd-physmap.txt b/Documentation/devicetree/bindings/mtd/mtd-physmap.txt index 80152cb..a63c2bd7 100644 --- a/Documentation/devicetree/bindings/mtd/mtd-physmap.txt +++ b/Documentation/devicetree/bindings/mtd/mtd-physmap.txt @@ -23,27 +23,8 @@ are defined: - vendor-id : Contains the flash chip's vendor id (1 byte). - device-id : Contains the flash chip's device id (1 byte). -In addition to the information on the mtd bank itself, the -device tree may optionally contain additional information -describing partitions of the address space. This can be -used on platforms which have strong conventions about which -portions of a flash are used for what purposes, but which don't -use an on-flash partition table such as RedBoot. - -Each partition is represented as a sub-node of the mtd device. -Each node's name represents the name of the corresponding -partition of the mtd device. - -Flash partitions - - reg : The partition's offset and size within the mtd bank. - - label : (optional) The label / name for this partition. - If omitted, the label is taken from the node name (excluding - the unit address). - - read-only : (optional) This parameter, if present, is a hint to - Linux that this partition should only be mounted - read-only. This is usually used for flash partitions - containing early-boot firmware images or data which should not - be clobbered. +The device tree may optionally contain sub-nodes describing partitions of the +address space. See partition.txt for more detail. Example: diff --git a/Documentation/devicetree/bindings/mtd/nand.txt b/Documentation/devicetree/bindings/mtd/nand.txt new file mode 100644 index 0000000..03855c8 --- /dev/null +++ b/Documentation/devicetree/bindings/mtd/nand.txt @@ -0,0 +1,7 @@ +* MTD generic binding + +- nand-ecc-mode : String, operation mode of the NAND ecc mode. + Supported values are: "none", "soft", "hw", "hw_syndrome", "hw_oob_first", + "soft_bch". +- nand-bus-width : 8 or 16 bus width if not present 8 +- nand-on-flash-bbt: boolean to enable on flash bbt option if not present false diff --git a/Documentation/devicetree/bindings/mtd/partition.txt b/Documentation/devicetree/bindings/mtd/partition.txt new file mode 100644 index 0000000..f114ce1 --- /dev/null +++ b/Documentation/devicetree/bindings/mtd/partition.txt @@ -0,0 +1,38 @@ +Representing flash partitions in devicetree + +Partitions can be represented by sub-nodes of an mtd device. This can be used +on platforms which have strong conventions about which portions of a flash are +used for what purposes, but which don't use an on-flash partition table such +as RedBoot. + +#address-cells & #size-cells must both be present in the mtd device and be +equal to 1. + +Required properties: +- reg : The partition's offset and size within the mtd bank. + +Optional properties: +- label : The label / name for this partition. If omitted, the label is taken + from the node name (excluding the unit address). +- read-only : This parameter, if present, is a hint to Linux that this + partition should only be mounted read-only. This is usually used for flash + partitions containing early-boot firmware images or data which should not be + clobbered. + +Examples: + + +flash@0 { + #address-cells = <1>; + #size-cells = <1>; + + partition@0 { + label = "u-boot"; + reg = <0x0000000 0x100000>; + read-only; + }; + + uimage@100000 { + reg = <0x0100000 0x200000>; + }; +]; diff --git a/Documentation/devicetree/bindings/usb/atmel-usb.txt b/Documentation/devicetree/bindings/usb/atmel-usb.txt new file mode 100644 index 0000000..60bd215 --- /dev/null +++ b/Documentation/devicetree/bindings/usb/atmel-usb.txt @@ -0,0 +1,49 @@ +Atmel SOC USB controllers + +OHCI + +Required properties: + - compatible: Should be "atmel,at91rm9200-ohci" for USB controllers + used in host mode. + - num-ports: Number of ports. + - atmel,vbus-gpio: If present, specifies a gpio that needs to be + activated for the bus to be powered. + - atmel,oc-gpio: If present, specifies a gpio that needs to be + activated for the overcurrent detection. + +usb0: ohci@00500000 { + compatible = "atmel,at91rm9200-ohci", "usb-ohci"; + reg = <0x00500000 0x100000>; + interrupts = <20 4>; + num-ports = <2>; +}; + +EHCI + +Required properties: + - compatible: Should be "atmel,at91sam9g45-ehci" for USB controllers + used in host mode. + +usb1: ehci@00800000 { + compatible = "atmel,at91sam9g45-ehci", "usb-ehci"; + reg = <0x00800000 0x100000>; + interrupts = <22 4>; +}; + +AT91 USB device controller + +Required properties: + - compatible: Should be "atmel,at91rm9200-udc" + - reg: Address and length of the register set for the device + - interrupts: Should contain macb interrupt + +Optional properties: + - atmel,vbus-gpio: If present, specifies a gpio that needs to be + activated for the bus to be powered. + +usb1: gadget@fffa4000 { + compatible = "atmel,at91rm9200-udc"; + reg = <0xfffa4000 0x4000>; + interrupts = <10 4>; + atmel,vbus-gpio = <&pioC 5 0>; +}; diff --git a/Documentation/devicetree/bindings/usb/tegra-usb.txt b/Documentation/devicetree/bindings/usb/tegra-usb.txt index 035d63d..007005d 100644 --- a/Documentation/devicetree/bindings/usb/tegra-usb.txt +++ b/Documentation/devicetree/bindings/usb/tegra-usb.txt @@ -11,3 +11,16 @@ Required properties : - phy_type : Should be one of "ulpi" or "utmi". - nvidia,vbus-gpio : If present, specifies a gpio that needs to be activated for the bus to be powered. + +Optional properties: + - dr_mode : dual role mode. Indicates the working mode for + nvidia,tegra20-ehci compatible controllers. Can be "host", "peripheral", + or "otg". Default to "host" if not defined for backward compatibility. + host means this is a host controller + peripheral means it is device controller + otg means it can operate as either ("on the go") + - nvidia,has-legacy-mode : boolean indicates whether this controller can + operate in legacy mode (as APX 2500 / 2600). In legacy mode some + registers are accessed through the APB_MISC base address instead of + the USB controller. Since this is a legacy issue it probably does not + warrant a compatible string of its own. diff --git a/Documentation/devicetree/usage-model.txt b/Documentation/devicetree/usage-model.txt new file mode 100644 index 0000000..c5a8009 --- /dev/null +++ b/Documentation/devicetree/usage-model.txt @@ -0,0 +1,412 @@ +Linux and the Device Tree +------------------------- +The Linux usage model for device tree data + +Author: Grant Likely <grant.likely@secretlab.ca> + +This article describes how Linux uses the device tree. An overview of +the device tree data format can be found on the device tree usage page +at devicetree.org[1]. + +[1] http://devicetree.org/Device_Tree_Usage + +The "Open Firmware Device Tree", or simply Device Tree (DT), is a data +structure and language for describing hardware. More specifically, it +is a description of hardware that is readable by an operating system +so that the operating system doesn't need to hard code details of the +machine. + +Structurally, the DT is a tree, or acyclic graph with named nodes, and +nodes may have an arbitrary number of named properties encapsulating +arbitrary data. A mechanism also exists to create arbitrary +links from one node to another outside of the natural tree structure. + +Conceptually, a common set of usage conventions, called 'bindings', +is defined for how data should appear in the tree to describe typical +hardware characteristics including data busses, interrupt lines, GPIO +connections, and peripheral devices. + +As much as possible, hardware is described using existing bindings to +maximize use of existing support code, but since property and node +names are simply text strings, it is easy to extend existing bindings +or create new ones by defining new nodes and properties. Be wary, +however, of creating a new binding without first doing some homework +about what already exists. There are currently two different, +incompatible, bindings for i2c busses that came about because the new +binding was created without first investigating how i2c devices were +already being enumerated in existing systems. + +1. History +---------- +The DT was originally created by Open Firmware as part of the +communication method for passing data from Open Firmware to a client +program (like to an operating system). An operating system used the +Device Tree to discover the topology of the hardware at runtime, and +thereby support a majority of available hardware without hard coded +information (assuming drivers were available for all devices). + +Since Open Firmware is commonly used on PowerPC and SPARC platforms, +the Linux support for those architectures has for a long time used the +Device Tree. + +In 2005, when PowerPC Linux began a major cleanup and to merge 32-bit +and 64-bit support, the decision was made to require DT support on all +powerpc platforms, regardless of whether or not they used Open +Firmware. To do this, a DT representation called the Flattened Device +Tree (FDT) was created which could be passed to the kernel as a binary +blob without requiring a real Open Firmware implementation. U-Boot, +kexec, and other bootloaders were modified to support both passing a +Device Tree Binary (dtb) and to modify a dtb at boot time. DT was +also added to the PowerPC boot wrapper (arch/powerpc/boot/*) so that +a dtb could be wrapped up with the kernel image to support booting +existing non-DT aware firmware. + +Some time later, FDT infrastructure was generalized to be usable by +all architectures. At the time of this writing, 6 mainlined +architectures (arm, microblaze, mips, powerpc, sparc, and x86) and 1 +out of mainline (nios) have some level of DT support. + +2. Data Model +------------- +If you haven't already read the Device Tree Usage[1] page, +then go read it now. It's okay, I'll wait.... + +2.1 High Level View +------------------- +The most important thing to understand is that the DT is simply a data +structure that describes the hardware. There is nothing magical about +it, and it doesn't magically make all hardware configuration problems +go away. What it does do is provide a language for decoupling the +hardware configuration from the board and device driver support in the +Linux kernel (or any other operating system for that matter). Using +it allows board and device support to become data driven; to make +setup decisions based on data passed into the kernel instead of on +per-machine hard coded selections. + +Ideally, data driven platform setup should result in less code +duplication and make it easier to support a wide range of hardware +with a single kernel image. + +Linux uses DT data for three major purposes: +1) platform identification, +2) runtime configuration, and +3) device population. + +2.2 Platform Identification +--------------------------- +First and foremost, the kernel will use data in the DT to identify the +specific machine. In a perfect world, the specific platform shouldn't +matter to the kernel because all platform details would be described +perfectly by the device tree in a consistent and reliable manner. +Hardware is not perfect though, and so the kernel must identify the +machine during early boot so that it has the opportunity to run +machine-specific fixups. + +In the majority of cases, the machine identity is irrelevant, and the +kernel will instead select setup code based on the machine's core +CPU or SoC. On ARM for example, setup_arch() in +arch/arm/kernel/setup.c will call setup_machine_fdt() in +arch/arm/kernel/devicetree.c which searches through the machine_desc +table and selects the machine_desc which best matches the device tree +data. It determines the best match by looking at the 'compatible' +property in the root device tree node, and comparing it with the +dt_compat list in struct machine_desc. + +The 'compatible' property contains a sorted list of strings starting +with the exact name of the machine, followed by an optional list of +boards it is compatible with sorted from most compatible to least. For +example, the root compatible properties for the TI BeagleBoard and its +successor, the BeagleBoard xM board might look like: + + compatible = "ti,omap3-beagleboard", "ti,omap3450", "ti,omap3"; + compatible = "ti,omap3-beagleboard-xm", "ti,omap3450", "ti,omap3"; + +Where "ti,omap3-beagleboard-xm" specifies the exact model, it also +claims that it compatible with the OMAP 3450 SoC, and the omap3 family +of SoCs in general. You'll notice that the list is sorted from most +specific (exact board) to least specific (SoC family). + +Astute readers might point out that the Beagle xM could also claim +compatibility with the original Beagle board. However, one should be +cautioned about doing so at the board level since there is typically a +high level of change from one board to another, even within the same +product line, and it is hard to nail down exactly what is meant when one +board claims to be compatible with another. For the top level, it is +better to err on the side of caution and not claim one board is +compatible with another. The notable exception would be when one +board is a carrier for another, such as a CPU module attached to a +carrier board. + +One more note on compatible values. Any string used in a compatible +property must be documented as to what it indicates. Add +documentation for compatible strings in Documentation/devicetree/bindings. + +Again on ARM, for each machine_desc, the kernel looks to see if +any of the dt_compat list entries appear in the compatible property. +If one does, then that machine_desc is a candidate for driving the +machine. After searching the entire table of machine_descs, +setup_machine_fdt() returns the 'most compatible' machine_desc based +on which entry in the compatible property each machine_desc matches +against. If no matching machine_desc is found, then it returns NULL. + +The reasoning behind this scheme is the observation that in the majority +of cases, a single machine_desc can support a large number of boards +if they all use the same SoC, or same family of SoCs. However, +invariably there will be some exceptions where a specific board will +require special setup code that is not useful in the generic case. +Special cases could be handled by explicitly checking for the +troublesome board(s) in generic setup code, but doing so very quickly +becomes ugly and/or unmaintainable if it is more than just a couple of +cases. + +Instead, the compatible list allows a generic machine_desc to provide +support for a wide common set of boards by specifying "less +compatible" value in the dt_compat list. In the example above, +generic board support can claim compatibility with "ti,omap3" or +"ti,omap3450". If a bug was discovered on the original beagleboard +that required special workaround code during early boot, then a new +machine_desc could be added which implements the workarounds and only +matches on "ti,omap3-beagleboard". + +PowerPC uses a slightly different scheme where it calls the .probe() +hook from each machine_desc, and the first one returning TRUE is used. +However, this approach does not take into account the priority of the +compatible list, and probably should be avoided for new architecture +support. + +2.3 Runtime configuration +------------------------- +In most cases, a DT will be the sole method of communicating data from +firmware to the kernel, so also gets used to pass in runtime and +configuration data like the kernel parameters string and the location +of an initrd image. + +Most of this data is contained in the /chosen node, and when booting +Linux it will look something like this: + + chosen { + bootargs = "console=ttyS0,115200 loglevel=8"; + initrd-start = <0xc8000000>; + initrd-end = <0xc8200000>; + }; + +The bootargs property contains the kernel arguments, and the initrd-* +properties define the address and size of an initrd blob. The +chosen node may also optionally contain an arbitrary number of +additional properties for platform-specific configuration data. + +During early boot, the architecture setup code calls of_scan_flat_dt() +several times with different helper callbacks to parse device tree +data before paging is setup. The of_scan_flat_dt() code scans through +the device tree and uses the helpers to extract information required +during early boot. Typically the early_init_dt_scan_chosen() helper +is used to parse the chosen node including kernel parameters, +early_init_dt_scan_root() to initialize the DT address space model, +and early_init_dt_scan_memory() to determine the size and +location of usable RAM. + +On ARM, the function setup_machine_fdt() is responsible for early +scanning of the device tree after selecting the correct machine_desc +that supports the board. + +2.4 Device population +--------------------- +After the board has been identified, and after the early configuration data +has been parsed, then kernel initialization can proceed in the normal +way. At some point in this process, unflatten_device_tree() is called +to convert the data into a more efficient runtime representation. +This is also when machine-specific setup hooks will get called, like +the machine_desc .init_early(), .init_irq() and .init_machine() hooks +on ARM. The remainder of this section uses examples from the ARM +implementation, but all architectures will do pretty much the same +thing when using a DT. + +As can be guessed by the names, .init_early() is used for any machine- +specific setup that needs to be executed early in the boot process, +and .init_irq() is used to set up interrupt handling. Using a DT +doesn't materially change the behaviour of either of these functions. +If a DT is provided, then both .init_early() and .init_irq() are able +to call any of the DT query functions (of_* in include/linux/of*.h) to +get additional data about the platform. + +The most interesting hook in the DT context is .init_machine() which +is primarily responsible for populating the Linux device model with +data about the platform. Historically this has been implemented on +embedded platforms by defining a set of static clock structures, +platform_devices, and other data in the board support .c file, and +registering it en-masse in .init_machine(). When DT is used, then +instead of hard coding static devices for each platform, the list of +devices can be obtained by parsing the DT, and allocating device +structures dynamically. + +The simplest case is when .init_machine() is only responsible for +registering a block of platform_devices. A platform_device is a concept +used by Linux for memory or I/O mapped devices which cannot be detected +by hardware, and for 'composite' or 'virtual' devices (more on those +later). While there is no 'platform device' terminology for the DT, +platform devices roughly correspond to device nodes at the root of the +tree and children of simple memory mapped bus nodes. + +About now is a good time to lay out an example. Here is part of the +device tree for the NVIDIA Tegra board. + +/{ + compatible = "nvidia,harmony", "nvidia,tegra20"; + #address-cells = <1>; + #size-cells = <1>; + interrupt-parent = <&intc>; + + chosen { }; + aliases { }; + + memory { + device_type = "memory"; + reg = <0x00000000 0x40000000>; + }; + + soc { + compatible = "nvidia,tegra20-soc", "simple-bus"; + #address-cells = <1>; + #size-cells = <1>; + ranges; + + intc: interrupt-controller@50041000 { + compatible = "nvidia,tegra20-gic"; + interrupt-controller; + #interrupt-cells = <1>; + reg = <0x50041000 0x1000>, < 0x50040100 0x0100 >; + }; + + serial@70006300 { + compatible = "nvidia,tegra20-uart"; + reg = <0x70006300 0x100>; + interrupts = <122>; + }; + + i2s1: i2s@70002800 { + compatible = "nvidia,tegra20-i2s"; + reg = <0x70002800 0x100>; + interrupts = <77>; + codec = <&wm8903>; + }; + + i2c@7000c000 { + compatible = "nvidia,tegra20-i2c"; + #address-cells = <1>; + #size-cells = <0>; + reg = <0x7000c000 0x100>; + interrupts = <70>; + + wm8903: codec@1a { + compatible = "wlf,wm8903"; + reg = <0x1a>; + interrupts = <347>; + }; + }; + }; + + sound { + compatible = "nvidia,harmony-sound"; + i2s-controller = <&i2s1>; + i2s-codec = <&wm8903>; + }; +}; + +At .machine_init() time, Tegra board support code will need to look at +this DT and decide which nodes to create platform_devices for. +However, looking at the tree, it is not immediately obvious what kind +of device each node represents, or even if a node represents a device +at all. The /chosen, /aliases, and /memory nodes are informational +nodes that don't describe devices (although arguably memory could be +considered a device). The children of the /soc node are memory mapped +devices, but the codec@1a is an i2c device, and the sound node +represents not a device, but rather how other devices are connected +together to create the audio subsystem. I know what each device is +because I'm familiar with the board design, but how does the kernel +know what to do with each node? + +The trick is that the kernel starts at the root of the tree and looks +for nodes that have a 'compatible' property. First, it is generally +assumed that any node with a 'compatible' property represents a device +of some kind, and second, it can be assumed that any node at the root +of the tree is either directly attached to the processor bus, or is a +miscellaneous system device that cannot be described any other way. +For each of these nodes, Linux allocates and registers a +platform_device, which in turn may get bound to a platform_driver. + +Why is using a platform_device for these nodes a safe assumption? +Well, for the way that Linux models devices, just about all bus_types +assume that its devices are children of a bus controller. For +example, each i2c_client is a child of an i2c_master. Each spi_device +is a child of an SPI bus. Similarly for USB, PCI, MDIO, etc. The +same hierarchy is also found in the DT, where I2C device nodes only +ever appear as children of an I2C bus node. Ditto for SPI, MDIO, USB, +etc. The only devices which do not require a specific type of parent +device are platform_devices (and amba_devices, but more on that +later), which will happily live at the base of the Linux /sys/devices +tree. Therefore, if a DT node is at the root of the tree, then it +really probably is best registered as a platform_device. + +Linux board support code calls of_platform_populate(NULL, NULL, NULL) +to kick off discovery of devices at the root of the tree. The +parameters are all NULL because when starting from the root of the +tree, there is no need to provide a starting node (the first NULL), a +parent struct device (the last NULL), and we're not using a match +table (yet). For a board that only needs to register devices, +.init_machine() can be completely empty except for the +of_platform_populate() call. + +In the Tegra example, this accounts for the /soc and /sound nodes, but +what about the children of the SoC node? Shouldn't they be registered +as platform devices too? For Linux DT support, the generic behaviour +is for child devices to be registered by the parent's device driver at +driver .probe() time. So, an i2c bus device driver will register a +i2c_client for each child node, an SPI bus driver will register +its spi_device children, and similarly for other bus_types. +According to that model, a driver could be written that binds to the +SoC node and simply registers platform_devices for each of its +children. The board support code would allocate and register an SoC +device, a (theoretical) SoC device driver could bind to the SoC device, +and register platform_devices for /soc/interrupt-controller, /soc/serial, +/soc/i2s, and /soc/i2c in its .probe() hook. Easy, right? + +Actually, it turns out that registering children of some +platform_devices as more platform_devices is a common pattern, and the +device tree support code reflects that and makes the above example +simpler. The second argument to of_platform_populate() is an +of_device_id table, and any node that matches an entry in that table +will also get its child nodes registered. In the tegra case, the code +can look something like this: + +static void __init harmony_init_machine(void) +{ + /* ... */ + of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL); +} + +"simple-bus" is defined in the ePAPR 1.0 specification as a property +meaning a simple memory mapped bus, so the of_platform_populate() code +could be written to just assume simple-bus compatible nodes will +always be traversed. However, we pass it in as an argument so that +board support code can always override the default behaviour. + +[Need to add discussion of adding i2c/spi/etc child devices] + +Appendix A: AMBA devices +------------------------ + +ARM Primecells are a certain kind of device attached to the ARM AMBA +bus which include some support for hardware detection and power +management. In Linux, struct amba_device and the amba_bus_type is +used to represent Primecell devices. However, the fiddly bit is that +not all devices on an AMBA bus are Primecells, and for Linux it is +typical for both amba_device and platform_device instances to be +siblings of the same bus segment. + +When using the DT, this creates problems for of_platform_populate() +because it must decide whether to register each node as either a +platform_device or an amba_device. This unfortunately complicates the +device creation model a little bit, but the solution turns out not to +be too invasive. If a node is compatible with "arm,amba-primecell", then +of_platform_populate() will register it as an amba_device instead of a +platform_device. diff --git a/Documentation/dma-buf-sharing.txt b/Documentation/dma-buf-sharing.txt index 225f96d..3bbd5c5 100644 --- a/Documentation/dma-buf-sharing.txt +++ b/Documentation/dma-buf-sharing.txt @@ -32,8 +32,12 @@ The buffer-user *IMPORTANT*: [see https://lkml.org/lkml/2011/12/20/211 for more details] For this first version, A buffer shared using the dma_buf sharing API: - *may* be exported to user space using "mmap" *ONLY* by exporter, outside of - this framework. -- may be used *ONLY* by importers that do not need CPU access to the buffer. + this framework. +- with this new iteration of the dma-buf api cpu access from the kernel has been + enable, see below for the details. + +dma-buf operations for device dma only +-------------------------------------- The dma_buf buffer sharing API usage contains the following steps: @@ -219,10 +223,120 @@ NOTES: If the exporter chooses not to allow an attach() operation once a map_dma_buf() API has been called, it simply returns an error. -Miscellaneous notes: +Kernel cpu access to a dma-buf buffer object +-------------------------------------------- + +The motivation to allow cpu access from the kernel to a dma-buf object from the +importers side are: +- fallback operations, e.g. if the devices is connected to a usb bus and the + kernel needs to shuffle the data around first before sending it away. +- full transparency for existing users on the importer side, i.e. userspace + should not notice the difference between a normal object from that subsystem + and an imported one backed by a dma-buf. This is really important for drm + opengl drivers that expect to still use all the existing upload/download + paths. + +Access to a dma_buf from the kernel context involves three steps: + +1. Prepare access, which invalidate any necessary caches and make the object + available for cpu access. +2. Access the object page-by-page with the dma_buf map apis +3. Finish access, which will flush any necessary cpu caches and free reserved + resources. + +1. Prepare access + + Before an importer can access a dma_buf object with the cpu from the kernel + context, it needs to notify the exporter of the access that is about to + happen. + + Interface: + int dma_buf_begin_cpu_access(struct dma_buf *dmabuf, + size_t start, size_t len, + enum dma_data_direction direction) + + This allows the exporter to ensure that the memory is actually available for + cpu access - the exporter might need to allocate or swap-in and pin the + backing storage. The exporter also needs to ensure that cpu access is + coherent for the given range and access direction. The range and access + direction can be used by the exporter to optimize the cache flushing, i.e. + access outside of the range or with a different direction (read instead of + write) might return stale or even bogus data (e.g. when the exporter needs to + copy the data to temporary storage). + + This step might fail, e.g. in oom conditions. + +2. Accessing the buffer + + To support dma_buf objects residing in highmem cpu access is page-based using + an api similar to kmap. Accessing a dma_buf is done in aligned chunks of + PAGE_SIZE size. Before accessing a chunk it needs to be mapped, which returns + a pointer in kernel virtual address space. Afterwards the chunk needs to be + unmapped again. There is no limit on how often a given chunk can be mapped + and unmapped, i.e. the importer does not need to call begin_cpu_access again + before mapping the same chunk again. + + Interfaces: + void *dma_buf_kmap(struct dma_buf *, unsigned long); + void dma_buf_kunmap(struct dma_buf *, unsigned long, void *); + + There are also atomic variants of these interfaces. Like for kmap they + facilitate non-blocking fast-paths. Neither the importer nor the exporter (in + the callback) is allowed to block when using these. + + Interfaces: + void *dma_buf_kmap_atomic(struct dma_buf *, unsigned long); + void dma_buf_kunmap_atomic(struct dma_buf *, unsigned long, void *); + + For importers all the restrictions of using kmap apply, like the limited + supply of kmap_atomic slots. Hence an importer shall only hold onto at most 2 + atomic dma_buf kmaps at the same time (in any given process context). + + dma_buf kmap calls outside of the range specified in begin_cpu_access are + undefined. If the range is not PAGE_SIZE aligned, kmap needs to succeed on + the partial chunks at the beginning and end but may return stale or bogus + data outside of the range (in these partial chunks). + + Note that these calls need to always succeed. The exporter needs to complete + any preparations that might fail in begin_cpu_access. + +3. Finish access + + When the importer is done accessing the range specified in begin_cpu_access, + it needs to announce this to the exporter (to facilitate cache flushing and + unpinning of any pinned resources). The result of of any dma_buf kmap calls + after end_cpu_access is undefined. + + Interface: + void dma_buf_end_cpu_access(struct dma_buf *dma_buf, + size_t start, size_t len, + enum dma_data_direction dir); + + +Miscellaneous notes +------------------- + - Any exporters or users of the dma-buf buffer sharing framework must have a 'select DMA_SHARED_BUFFER' in their respective Kconfigs. +- In order to avoid fd leaks on exec, the FD_CLOEXEC flag must be set + on the file descriptor. This is not just a resource leak, but a + potential security hole. It could give the newly exec'd application + access to buffers, via the leaked fd, to which it should otherwise + not be permitted access. + + The problem with doing this via a separate fcntl() call, versus doing it + atomically when the fd is created, is that this is inherently racy in a + multi-threaded app[3]. The issue is made worse when it is library code + opening/creating the file descriptor, as the application may not even be + aware of the fd's. + + To avoid this problem, userspace must have a way to request O_CLOEXEC + flag be set when the dma-buf fd is created. So any API provided by + the exporting driver to create a dmabuf fd must provide a way to let + userspace control setting of O_CLOEXEC flag passed in to dma_buf_fd(). + References: [1] struct dma_buf_ops in include/linux/dma-buf.h [2] All interfaces mentioned above defined in include/linux/dma-buf.h +[3] https://lwn.net/Articles/236486/ diff --git a/Documentation/filesystems/ext4.txt b/Documentation/filesystems/ext4.txt index 8c10bf3..1b7f9ac 100644 --- a/Documentation/filesystems/ext4.txt +++ b/Documentation/filesystems/ext4.txt @@ -144,9 +144,6 @@ journal_async_commit Commit block can be written to disk without waiting mount the device. This will enable 'journal_checksum' internally. -journal=update Update the ext4 file system's journal to the current - format. - journal_dev=devnum When the external journal device's major/minor numbers have changed, this option allows the user to specify the new journal location. The journal device is @@ -356,11 +353,6 @@ nouid32 Disables 32-bit UIDs and GIDs. This is for interoperability with older kernels which only store and expect 16-bit values. -resize Allows to resize filesystem to the end of the last - existing block group, further resize has to be done - with resize2fs either online, or offline. It can be - used only with conjunction with remount. - block_validity This options allows to enables/disables the in-kernel noblock_validity facility for tracking filesystem metadata blocks within internal data structures. This allows multi- diff --git a/Documentation/filesystems/files.txt b/Documentation/filesystems/files.txt index ac2facc..46dfc6b 100644 --- a/Documentation/filesystems/files.txt +++ b/Documentation/filesystems/files.txt @@ -113,8 +113,8 @@ the fdtable structure - if (fd >= 0) { /* locate_fd() may have expanded fdtable, load the ptr */ fdt = files_fdtable(files); - FD_SET(fd, fdt->open_fds); - FD_CLR(fd, fdt->close_on_exec); + __set_open_fd(fd, fdt); + __clear_close_on_exec(fd, fdt); spin_unlock(&files->file_lock); ..... diff --git a/Documentation/gpio.txt b/Documentation/gpio.txt index 792faa3..620a078 100644 --- a/Documentation/gpio.txt +++ b/Documentation/gpio.txt @@ -271,9 +271,26 @@ Some platforms may also use knowledge about what GPIOs are active for power management, such as by powering down unused chip sectors and, more easily, gating off unused clocks. -Note that requesting a GPIO does NOT cause it to be configured in any -way; it just marks that GPIO as in use. Separate code must handle any -pin setup (e.g. controlling which pin the GPIO uses, pullup/pulldown). +For GPIOs that use pins known to the pinctrl subsystem, that subsystem should +be informed of their use; a gpiolib driver's .request() operation may call +pinctrl_request_gpio(), and a gpiolib driver's .free() operation may call +pinctrl_free_gpio(). The pinctrl subsystem allows a pinctrl_request_gpio() +to succeed concurrently with a pin or pingroup being "owned" by a device for +pin multiplexing. + +Any programming of pin multiplexing hardware that is needed to route the +GPIO signal to the appropriate pin should occur within a GPIO driver's +.direction_input() or .direction_output() operations, and occur after any +setup of an output GPIO's value. This allows a glitch-free migration from a +pin's special function to GPIO. This is sometimes required when using a GPIO +to implement a workaround on signals typically driven by a non-GPIO HW block. + +Some platforms allow some or all GPIO signals to be routed to different pins. +Similarly, other aspects of the GPIO or pin may need to be configured, such as +pullup/pulldown. Platform software should arrange that any such details are +configured prior to gpio_request() being called for those GPIOs, e.g. using +the pinctrl subsystem's mapping table, so that GPIO users need not be aware +of these details. Also note that it's your responsibility to have stopped using a GPIO before you free it. @@ -302,6 +319,8 @@ where 'flags' is currently defined to specify the following properties: * GPIOF_INIT_LOW - as output, set initial level to LOW * GPIOF_INIT_HIGH - as output, set initial level to HIGH + * GPIOF_OPEN_DRAIN - gpio pin is open drain type. + * GPIOF_OPEN_SOURCE - gpio pin is open source type. since GPIOF_INIT_* are only valid when configured as output, so group valid combinations as: @@ -310,8 +329,19 @@ combinations as: * GPIOF_OUT_INIT_LOW - configured as output, initial level LOW * GPIOF_OUT_INIT_HIGH - configured as output, initial level HIGH -In the future, these flags can be extended to support more properties such -as open-drain status. +When setting the flag as GPIOF_OPEN_DRAIN then it will assume that pins is +open drain type. Such pins will not be driven to 1 in output mode. It is +require to connect pull-up on such pins. By enabling this flag, gpio lib will +make the direction to input when it is asked to set value of 1 in output mode +to make the pin HIGH. The pin is make to LOW by driving value 0 in output mode. + +When setting the flag as GPIOF_OPEN_SOURCE then it will assume that pins is +open source type. Such pins will not be driven to 0 in output mode. It is +require to connect pull-down on such pin. By enabling this flag, gpio lib will +make the direction to input when it is asked to set value of 0 in output mode +to make the pin LOW. The pin is make to HIGH by driving value 1 in output mode. + +In the future, these flags can be extended to support more properties. Further more, to ease the claim/release of multiple GPIOs, 'struct gpio' is introduced to encapsulate all three fields as: diff --git a/Documentation/i2c/busses/i2c-i801 b/Documentation/i2c/busses/i2c-i801 index 2871fd5..71f55bb 100644 --- a/Documentation/i2c/busses/i2c-i801 +++ b/Documentation/i2c/busses/i2c-i801 @@ -20,6 +20,7 @@ Supported adapters: * Intel Patsburg (PCH) * Intel DH89xxCC (PCH) * Intel Panther Point (PCH) + * Intel Lynx Point (PCH) Datasheets: Publicly available at the Intel website On Intel Patsburg and later chipsets, both the normal host SMBus controller diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 58eac23..c1601e5 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1699,6 +1699,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted. The default is to send the implementation identification information. + nfsd.nfs4_disable_idmapping= + [NFSv4] When set to the default of '1', the NFSv4 + server will return only numeric uids and gids to + clients using auth_sys, and will accept numeric uids + and gids from such clients. This is intended to ease + migration from NFSv2/v3. objlayoutdriver.osd_login_prog= [NFS] [OBJLAYOUT] sets the pathname to the program which @@ -1869,6 +1875,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted. shutdown the other cpus. Instead use the REBOOT_VECTOR irq. + nomodule Disable module load + nopat [X86] Disable PAT (page attribute table extension of pagetables) support. diff --git a/Documentation/laptops/asus-laptop.txt b/Documentation/laptops/asus-laptop.txt index 803e51f..a1e04d6 100644 --- a/Documentation/laptops/asus-laptop.txt +++ b/Documentation/laptops/asus-laptop.txt @@ -45,7 +45,7 @@ Status Usage ----- - Try "modprobe asus_acpi". Check your dmesg (simply type dmesg). You should + Try "modprobe asus-laptop". Check your dmesg (simply type dmesg). You should see some lines like this : Asus Laptop Extras version 0.42 diff --git a/Documentation/laptops/sony-laptop.txt b/Documentation/laptops/sony-laptop.txt index 2bd4e82..0d5ac7f 100644 --- a/Documentation/laptops/sony-laptop.txt +++ b/Documentation/laptops/sony-laptop.txt @@ -17,6 +17,11 @@ subsystem. See the logs of acpid or /proc/acpi/event and devices are created by the driver. Additionally, loading the driver with the debug option will report all events in the kernel log. +The "scancodes" passed to the input system (that can be remapped with udev) +are indexes to the table "sony_laptop_input_keycode_map" in the sony-laptop.c +module. For example the "FN/E" key combination (EJECTCD on some models) +generates the scancode 20 (0x14). + Backlight control: ------------------ If your laptop model supports it, you will find sysfs files in the diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index e1d94bf..6386f8c 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -95,7 +95,7 @@ described as 'basic' will be available. Capability: basic Architectures: all Type: system ioctl -Parameters: none +Parameters: machine type identifier (KVM_VM_*) Returns: a VM fd that can be used to control the new virtual machine. The new VM has no virtual cpus and no memory. An mmap() of a VM fd @@ -103,6 +103,11 @@ will access the virtual machine's physical address space; offset zero corresponds to guest physical address zero. Use of mmap() on a VM fd is discouraged if userspace memory allocation (KVM_CAP_USER_MEMORY) is available. +You most certainly want to use 0 as machine type. + +In order to create user controlled virtual machines on S390, check +KVM_CAP_S390_UCONTROL and use the flag KVM_VM_S390_UCONTROL as +privileged user (CAP_SYS_ADMIN). 4.3 KVM_GET_MSR_INDEX_LIST @@ -213,6 +218,11 @@ allocation of vcpu ids. For example, if userspace wants single-threaded guest vcpus, it should make all vcpu ids be a multiple of the number of vcpus per vcore. +For virtual cpus that have been created with S390 user controlled virtual +machines, the resulting vcpu fd can be memory mapped at page offset +KVM_S390_SIE_PAGE_OFFSET in order to obtain a memory map of the virtual +cpu's hardware control block. + 4.8 KVM_GET_DIRTY_LOG (vm ioctl) Capability: basic @@ -1159,6 +1169,14 @@ following flags are specified: /* Depends on KVM_CAP_IOMMU */ #define KVM_DEV_ASSIGN_ENABLE_IOMMU (1 << 0) +/* The following two depend on KVM_CAP_PCI_2_3 */ +#define KVM_DEV_ASSIGN_PCI_2_3 (1 << 1) +#define KVM_DEV_ASSIGN_MASK_INTX (1 << 2) + +If KVM_DEV_ASSIGN_PCI_2_3 is set, the kernel will manage legacy INTx interrupts +via the PCI-2.3-compliant device-level mask, thus enable IRQ sharing with other +assigned devices or host devices. KVM_DEV_ASSIGN_MASK_INTX specifies the +guest's view on the INTx mask, see KVM_ASSIGN_SET_INTX_MASK for details. The KVM_DEV_ASSIGN_ENABLE_IOMMU flag is a mandatory option to ensure isolation of the device. Usages not specifying this flag are deprecated. @@ -1399,6 +1417,71 @@ The following flags are defined: If datamatch flag is set, the event will be signaled only if the written value to the registered address is equal to datamatch in struct kvm_ioeventfd. +4.59 KVM_DIRTY_TLB + +Capability: KVM_CAP_SW_TLB +Architectures: ppc +Type: vcpu ioctl +Parameters: struct kvm_dirty_tlb (in) +Returns: 0 on success, -1 on error + +struct kvm_dirty_tlb { + __u64 bitmap; + __u32 num_dirty; +}; + +This must be called whenever userspace has changed an entry in the shared +TLB, prior to calling KVM_RUN on the associated vcpu. + +The "bitmap" field is the userspace address of an array. This array +consists of a number of bits, equal to the total number of TLB entries as +determined by the last successful call to KVM_CONFIG_TLB, rounded up to the +nearest multiple of 64. + +Each bit corresponds to one TLB entry, ordered the same as in the shared TLB +array. + +The array is little-endian: the bit 0 is the least significant bit of the +first byte, bit 8 is the least significant bit of the second byte, etc. +This avoids any complications with differing word sizes. + +The "num_dirty" field is a performance hint for KVM to determine whether it +should skip processing the bitmap and just invalidate everything. It must +be set to the number of set bits in the bitmap. + +4.60 KVM_ASSIGN_SET_INTX_MASK + +Capability: KVM_CAP_PCI_2_3 +Architectures: x86 +Type: vm ioctl +Parameters: struct kvm_assigned_pci_dev (in) +Returns: 0 on success, -1 on error + +Allows userspace to mask PCI INTx interrupts from the assigned device. The +kernel will not deliver INTx interrupts to the guest between setting and +clearing of KVM_ASSIGN_SET_INTX_MASK via this interface. This enables use of +and emulation of PCI 2.3 INTx disable command register behavior. + +This may be used for both PCI 2.3 devices supporting INTx disable natively and +older devices lacking this support. Userspace is responsible for emulating the +read value of the INTx disable bit in the guest visible PCI command register. +When modifying the INTx disable state, userspace should precede updating the +physical device command register by calling this ioctl to inform the kernel of +the new intended INTx mask state. + +Note that the kernel uses the device INTx disable bit to internally manage the +device interrupt state for PCI 2.3 devices. Reads of this register may +therefore not match the expected value. Writes should always use the guest +intended INTx disable value rather than attempting to read-copy-update the +current physical device state. Races between user and kernel updates to the +INTx disable bit are handled lazily in the kernel. It's possible the device +may generate unintended interrupts, but they will not be injected into the +guest. + +See KVM_ASSIGN_DEV_IRQ for the data structure. The target device is specified +by assigned_dev_id. In the flags field, only KVM_DEV_ASSIGN_MASK_INTX is +evaluated. + 4.62 KVM_CREATE_SPAPR_TCE Capability: KVM_CAP_SPAPR_TCE @@ -1491,6 +1574,101 @@ following algorithm: Some guests configure the LINT1 NMI input to cause a panic, aiding in debugging. +4.65 KVM_S390_UCAS_MAP + +Capability: KVM_CAP_S390_UCONTROL +Architectures: s390 +Type: vcpu ioctl +Parameters: struct kvm_s390_ucas_mapping (in) +Returns: 0 in case of success + +The parameter is defined like this: + struct kvm_s390_ucas_mapping { + __u64 user_addr; + __u64 vcpu_addr; + __u64 length; + }; + +This ioctl maps the memory at "user_addr" with the length "length" to +the vcpu's address space starting at "vcpu_addr". All parameters need to +be alligned by 1 megabyte. + +4.66 KVM_S390_UCAS_UNMAP + +Capability: KVM_CAP_S390_UCONTROL +Architectures: s390 +Type: vcpu ioctl +Parameters: struct kvm_s390_ucas_mapping (in) +Returns: 0 in case of success + +The parameter is defined like this: + struct kvm_s390_ucas_mapping { + __u64 user_addr; + __u64 vcpu_addr; + __u64 length; + }; + +This ioctl unmaps the memory in the vcpu's address space starting at +"vcpu_addr" with the length "length". The field "user_addr" is ignored. +All parameters need to be alligned by 1 megabyte. + +4.67 KVM_S390_VCPU_FAULT + +Capability: KVM_CAP_S390_UCONTROL +Architectures: s390 +Type: vcpu ioctl +Parameters: vcpu absolute address (in) +Returns: 0 in case of success + +This call creates a page table entry on the virtual cpu's address space +(for user controlled virtual machines) or the virtual machine's address +space (for regular virtual machines). This only works for minor faults, +thus it's recommended to access subject memory page via the user page +table upfront. This is useful to handle validity intercepts for user +controlled virtual machines to fault in the virtual cpu's lowcore pages +prior to calling the KVM_RUN ioctl. + +4.68 KVM_SET_ONE_REG + +Capability: KVM_CAP_ONE_REG +Architectures: all +Type: vcpu ioctl +Parameters: struct kvm_one_reg (in) +Returns: 0 on success, negative value on failure + +struct kvm_one_reg { + __u64 id; + __u64 addr; +}; + +Using this ioctl, a single vcpu register can be set to a specific value +defined by user space with the passed in struct kvm_one_reg, where id +refers to the register identifier as described below and addr is a pointer +to a variable with the respective size. There can be architecture agnostic +and architecture specific registers. Each have their own range of operation +and their own constants and width. To keep track of the implemented +registers, find a list below: + + Arch | Register | Width (bits) + | | + PPC | KVM_REG_PPC_HIOR | 64 + +4.69 KVM_GET_ONE_REG + +Capability: KVM_CAP_ONE_REG +Architectures: all +Type: vcpu ioctl +Parameters: struct kvm_one_reg (in and out) +Returns: 0 on success, negative value on failure + +This ioctl allows to receive the value of a single register implemented +in a vcpu. The register to read is indicated by the "id" field of the +kvm_one_reg struct passed in. On success, the register value can be found +at the memory location pointed to by "addr". + +The list of registers accessible using this interface is identical to the +list in 4.64. + 5. The kvm_run structure Application code obtains a pointer to the kvm_run structure by @@ -1651,6 +1829,20 @@ s390 specific. s390 specific. + /* KVM_EXIT_S390_UCONTROL */ + struct { + __u64 trans_exc_code; + __u32 pgm_code; + } s390_ucontrol; + +s390 specific. A page fault has occurred for a user controlled virtual +machine (KVM_VM_S390_UNCONTROL) on it's host page table that cannot be +resolved by the kernel. +The program code and the translation exception code that were placed +in the cpu's lowcore are presented here as defined by the z Architecture +Principles of Operation Book in the Chapter for Dynamic Address Translation +(DAT) + /* KVM_EXIT_DCR */ struct { __u32 dcrn; @@ -1693,6 +1885,29 @@ developer registration required to access it). /* Fix the size of the union. */ char padding[256]; }; + + /* + * shared registers between kvm and userspace. + * kvm_valid_regs specifies the register classes set by the host + * kvm_dirty_regs specified the register classes dirtied by userspace + * struct kvm_sync_regs is architecture specific, as well as the + * bits for kvm_valid_regs and kvm_dirty_regs + */ + __u64 kvm_valid_regs; + __u64 kvm_dirty_regs; + union { + struct kvm_sync_regs regs; + char padding[1024]; + } s; + +If KVM_CAP_SYNC_REGS is defined, these fields allow userspace to access +certain guest registers without having to call SET/GET_*REGS. Thus we can +avoid some system call overhead if userspace has to handle the exit. +Userspace can query the validity of the structure by checking +kvm_valid_regs for specific bits. These bits are architecture specific +and usually define the validity of a groups of registers. (e.g. one bit + for general purpose registers) + }; 6. Capabilities that can be enabled @@ -1741,3 +1956,45 @@ HTAB address part of SDR1 contains an HVA instead of a GPA, as PAPR keeps the HTAB invisible to the guest. When this capability is enabled, KVM_EXIT_PAPR_HCALL can occur. + +6.3 KVM_CAP_SW_TLB + +Architectures: ppc +Parameters: args[0] is the address of a struct kvm_config_tlb +Returns: 0 on success; -1 on error + +struct kvm_config_tlb { + __u64 params; + __u64 array; + __u32 mmu_type; + __u32 array_len; +}; + +Configures the virtual CPU's TLB array, establishing a shared memory area +between userspace and KVM. The "params" and "array" fields are userspace +addresses of mmu-type-specific data structures. The "array_len" field is an +safety mechanism, and should be set to the size in bytes of the memory that +userspace has reserved for the array. It must be at least the size dictated +by "mmu_type" and "params". + +While KVM_RUN is active, the shared region is under control of KVM. Its +contents are undefined, and any modification by userspace results in +boundedly undefined behavior. + +On return from KVM_RUN, the shared region will reflect the current state of +the guest's TLB. If userspace makes any changes, it must call KVM_DIRTY_TLB +to tell KVM which entries have been changed, prior to calling KVM_RUN again +on this vcpu. + +For mmu types KVM_MMU_FSL_BOOKE_NOHV and KVM_MMU_FSL_BOOKE_HV: + - The "params" field is of type "struct kvm_book3e_206_tlb_params". + - The "array" field points to an array of type "struct + kvm_book3e_206_tlb_entry". + - The array consists of all entries in the first TLB, followed by all + entries in the second TLB. + - Within a TLB, entries are ordered first by increasing set number. Within a + set, entries are ordered by way (increasing ESEL). + - The hash for determining set number in TLB0 is: (MAS2 >> 12) & (num_sets - 1) + where "num_sets" is the tlb_sizes[] value divided by the tlb_ways[] value. + - The tsize field of mas1 shall be set to 4K on TLB0, even though the + hardware ignores this value for TLB0. diff --git a/Documentation/virtual/kvm/ppc-pv.txt b/Documentation/virtual/kvm/ppc-pv.txt index 2b7ce19..6e7c370 100644 --- a/Documentation/virtual/kvm/ppc-pv.txt +++ b/Documentation/virtual/kvm/ppc-pv.txt @@ -81,28 +81,8 @@ additional registers to the magic page. If you add fields to the magic page, also define a new hypercall feature to indicate that the host can give you more registers. Only if the host supports the additional features, make use of them. -The magic page has the following layout as described in -arch/powerpc/include/asm/kvm_para.h: - -struct kvm_vcpu_arch_shared { - __u64 scratch1; - __u64 scratch2; - __u64 scratch3; - __u64 critical; /* Guest may not get interrupts if == r1 */ - __u64 sprg0; - __u64 sprg1; - __u64 sprg2; - __u64 sprg3; - __u64 srr0; - __u64 srr1; - __u64 dar; - __u64 msr; - __u32 dsisr; - __u32 int_pending; /* Tells the guest if we have an interrupt */ -}; - -Additions to the page must only occur at the end. Struct fields are always 32 -or 64 bit aligned, depending on them being 32 or 64 bit wide respectively. +The magic page layout is described by struct kvm_vcpu_arch_shared +in arch/powerpc/include/asm/kvm_para.h. Magic page features =================== diff --git a/Documentation/vm/Makefile b/Documentation/vm/Makefile deleted file mode 100644 index 3fa4d06..0000000 --- a/Documentation/vm/Makefile +++ /dev/null @@ -1,8 +0,0 @@ -# kbuild trick to avoid linker error. Can be omitted if a module is built. -obj- := dummy.o - -# List of programs to build -hostprogs-y := page-types hugepage-mmap hugepage-shm map_hugetlb - -# Tell kbuild to always build the programs -always := $(hostprogs-y) diff --git a/Documentation/vm/hugepage-mmap.c b/Documentation/vm/hugepage-mmap.c deleted file mode 100644 index db0dd9a..0000000 --- a/Documentation/vm/hugepage-mmap.c +++ /dev/null @@ -1,91 +0,0 @@ -/* - * hugepage-mmap: - * - * Example of using huge page memory in a user application using the mmap - * system call. Before running this application, make sure that the - * administrator has mounted the hugetlbfs filesystem (on some directory - * like /mnt) using the command mount -t hugetlbfs nodev /mnt. In this - * example, the app is requesting memory of size 256MB that is backed by - * huge pages. - * - * For the ia64 architecture, the Linux kernel reserves Region number 4 for - * huge pages. That means that if one requires a fixed address, a huge page - * aligned address starting with 0x800000... will be required. If a fixed - * address is not required, the kernel will select an address in the proper - * range. - * Other architectures, such as ppc64, i386 or x86_64 are not so constrained. - */ - -#include <stdlib.h> -#include <stdio.h> -#include <unistd.h> -#include <sys/mman.h> -#include <fcntl.h> - -#define FILE_NAME "/mnt/hugepagefile" -#define LENGTH (256UL*1024*1024) -#define PROTECTION (PROT_READ | PROT_WRITE) - -/* Only ia64 requires this */ -#ifdef __ia64__ -#define ADDR (void *)(0x8000000000000000UL) -#define FLAGS (MAP_SHARED | MAP_FIXED) -#else -#define ADDR (void *)(0x0UL) -#define FLAGS (MAP_SHARED) -#endif - -static void check_bytes(char *addr) -{ - printf("First hex is %x\n", *((unsigned int *)addr)); -} - -static void write_bytes(char *addr) -{ - unsigned long i; - - for (i = 0; i < LENGTH; i++) - *(addr + i) = (char)i; -} - -static void read_bytes(char *addr) -{ - unsigned long i; - - check_bytes(addr); - for (i = 0; i < LENGTH; i++) - if (*(addr + i) != (char)i) { - printf("Mismatch at %lu\n", i); - break; - } -} - -int main(void) -{ - void *addr; - int fd; - - fd = open(FILE_NAME, O_CREAT | O_RDWR, 0755); - if (fd < 0) { - perror("Open failed"); - exit(1); - } - - addr = mmap(ADDR, LENGTH, PROTECTION, FLAGS, fd, 0); - if (addr == MAP_FAILED) { - perror("mmap"); - unlink(FILE_NAME); - exit(1); - } - - printf("Returned address is %p\n", addr); - check_bytes(addr); - write_bytes(addr); - read_bytes(addr); - - munmap(addr, LENGTH); - close(fd); - unlink(FILE_NAME); - - return 0; -} diff --git a/Documentation/vm/hugepage-shm.c b/Documentation/vm/hugepage-shm.c deleted file mode 100644 index 07956d8..0000000 --- a/Documentation/vm/hugepage-shm.c +++ /dev/null @@ -1,98 +0,0 @@ -/* - * hugepage-shm: - * - * Example of using huge page memory in a user application using Sys V shared - * memory system calls. In this example the app is requesting 256MB of - * memory that is backed by huge pages. The application uses the flag - * SHM_HUGETLB in the shmget system call to inform the kernel that it is - * requesting huge pages. - * - * For the ia64 architecture, the Linux kernel reserves Region number 4 for - * huge pages. That means that if one requires a fixed address, a huge page - * aligned address starting with 0x800000... will be required. If a fixed - * address is not required, the kernel will select an address in the proper - * range. - * Other architectures, such as ppc64, i386 or x86_64 are not so constrained. - * - * Note: The default shared memory limit is quite low on many kernels, - * you may need to increase it via: - * - * echo 268435456 > /proc/sys/kernel/shmmax - * - * This will increase the maximum size per shared memory segment to 256MB. - * The other limit that you will hit eventually is shmall which is the - * total amount of shared memory in pages. To set it to 16GB on a system - * with a 4kB pagesize do: - * - * echo 4194304 > /proc/sys/kernel/shmall - */ - -#include <stdlib.h> -#include <stdio.h> -#include <sys/types.h> -#include <sys/ipc.h> -#include <sys/shm.h> -#include <sys/mman.h> - -#ifndef SHM_HUGETLB -#define SHM_HUGETLB 04000 -#endif - -#define LENGTH (256UL*1024*1024) - -#define dprintf(x) printf(x) - -/* Only ia64 requires this */ -#ifdef __ia64__ -#define ADDR (void *)(0x8000000000000000UL) -#define SHMAT_FLAGS (SHM_RND) -#else -#define ADDR (void *)(0x0UL) -#define SHMAT_FLAGS (0) -#endif - -int main(void) -{ - int shmid; - unsigned long i; - char *shmaddr; - - if ((shmid = shmget(2, LENGTH, - SHM_HUGETLB | IPC_CREAT | SHM_R | SHM_W)) < 0) { - perror("shmget"); - exit(1); - } - printf("shmid: 0x%x\n", shmid); - - shmaddr = shmat(shmid, ADDR, SHMAT_FLAGS); - if (shmaddr == (char *)-1) { - perror("Shared memory attach failure"); - shmctl(shmid, IPC_RMID, NULL); - exit(2); - } - printf("shmaddr: %p\n", shmaddr); - - dprintf("Starting the writes:\n"); - for (i = 0; i < LENGTH; i++) { - shmaddr[i] = (char)(i); - if (!(i % (1024 * 1024))) - dprintf("."); - } - dprintf("\n"); - - dprintf("Starting the Check..."); - for (i = 0; i < LENGTH; i++) - if (shmaddr[i] != (char)i) - printf("\nIndex %lu mismatched\n", i); - dprintf("Done.\n"); - - if (shmdt((const void *)shmaddr) != 0) { - perror("Detach failure"); - shmctl(shmid, IPC_RMID, NULL); - exit(3); - } - - shmctl(shmid, IPC_RMID, NULL); - - return 0; -} diff --git a/Documentation/vm/map_hugetlb.c b/Documentation/vm/map_hugetlb.c deleted file mode 100644 index eda1a6d..0000000 --- a/Documentation/vm/map_hugetlb.c +++ /dev/null @@ -1,77 +0,0 @@ -/* - * Example of using hugepage memory in a user application using the mmap - * system call with MAP_HUGETLB flag. Before running this program make - * sure the administrator has allocated enough default sized huge pages - * to cover the 256 MB allocation. - * - * For ia64 architecture, Linux kernel reserves Region number 4 for hugepages. - * That means the addresses starting with 0x800000... will need to be - * specified. Specifying a fixed address is not required on ppc64, i386 - * or x86_64. - */ -#include <stdlib.h> -#include <stdio.h> -#include <unistd.h> -#include <sys/mman.h> -#include <fcntl.h> - -#define LENGTH (256UL*1024*1024) -#define PROTECTION (PROT_READ | PROT_WRITE) - -#ifndef MAP_HUGETLB -#define MAP_HUGETLB 0x40000 /* arch specific */ -#endif - -/* Only ia64 requires this */ -#ifdef __ia64__ -#define ADDR (void *)(0x8000000000000000UL) -#define FLAGS (MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB | MAP_FIXED) -#else -#define ADDR (void *)(0x0UL) -#define FLAGS (MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB) -#endif - -static void check_bytes(char *addr) -{ - printf("First hex is %x\n", *((unsigned int *)addr)); -} - -static void write_bytes(char *addr) -{ - unsigned long i; - - for (i = 0; i < LENGTH; i++) - *(addr + i) = (char)i; -} - -static void read_bytes(char *addr) -{ - unsigned long i; - - check_bytes(addr); - for (i = 0; i < LENGTH; i++) - if (*(addr + i) != (char)i) { - printf("Mismatch at %lu\n", i); - break; - } -} - -int main(void) -{ - void *addr; - - addr = mmap(ADDR, LENGTH, PROTECTION, FLAGS, 0, 0); - if (addr == MAP_FAILED) { - perror("mmap"); - exit(1); - } - - printf("Returned address is %p\n", addr); - check_bytes(addr); - write_bytes(addr); - read_bytes(addr); - - munmap(addr, LENGTH); - - return 0; -} diff --git a/Documentation/vm/page-types.c b/Documentation/vm/page-types.c deleted file mode 100644 index 0b13f02..0000000 --- a/Documentation/vm/page-types.c +++ /dev/null @@ -1,1102 +0,0 @@ -/* - * page-types: Tool for querying page flags - * - * This program is free software; you can redistribute it and/or modify it - * under the terms of the GNU General Public License as published by the Free - * Software Foundation; version 2. - * - * This program is distributed in the hope that it will be useful, but WITHOUT - * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or - * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for - * more details. - * - * You should find a copy of v2 of the GNU General Public License somewhere on - * your Linux system; if not, write to the Free Software Foundation, Inc., 59 - * Temple Place, Suite 330, Boston, MA 02111-1307 USA. - * - * Copyright (C) 2009 Intel corporation - * - * Authors: Wu Fengguang <fengguang.wu@intel.com> - */ - -#define _LARGEFILE64_SOURCE -#include <stdio.h> -#include <stdlib.h> -#include <unistd.h> -#include <stdint.h> -#include <stdarg.h> -#include <string.h> -#include <getopt.h> -#include <limits.h> -#include <assert.h> -#include <sys/types.h> -#include <sys/errno.h> -#include <sys/fcntl.h> -#include <sys/mount.h> -#include <sys/statfs.h> -#include "../../include/linux/magic.h" - - -#ifndef MAX_PATH -# define MAX_PATH 256 -#endif - -#ifndef STR -# define _STR(x) #x -# define STR(x) _STR(x) -#endif - -/* - * pagemap kernel ABI bits - */ - -#define PM_ENTRY_BYTES sizeof(uint64_t) -#define PM_STATUS_BITS 3 -#define PM_STATUS_OFFSET (64 - PM_STATUS_BITS) -#define PM_STATUS_MASK (((1LL << PM_STATUS_BITS) - 1) << PM_STATUS_OFFSET) -#define PM_STATUS(nr) (((nr) << PM_STATUS_OFFSET) & PM_STATUS_MASK) -#define PM_PSHIFT_BITS 6 -#define PM_PSHIFT_OFFSET (PM_STATUS_OFFSET - PM_PSHIFT_BITS) -#define PM_PSHIFT_MASK (((1LL << PM_PSHIFT_BITS) - 1) << PM_PSHIFT_OFFSET) -#define PM_PSHIFT(x) (((u64) (x) << PM_PSHIFT_OFFSET) & PM_PSHIFT_MASK) -#define PM_PFRAME_MASK ((1LL << PM_PSHIFT_OFFSET) - 1) -#define PM_PFRAME(x) ((x) & PM_PFRAME_MASK) - -#define PM_PRESENT PM_STATUS(4LL) -#define PM_SWAP PM_STATUS(2LL) - - -/* - * kernel page flags - */ - -#define KPF_BYTES 8 -#define PROC_KPAGEFLAGS "/proc/kpageflags" - -/* copied from kpageflags_read() */ -#define KPF_LOCKED 0 -#define KPF_ERROR 1 -#define KPF_REFERENCED 2 -#define KPF_UPTODATE 3 -#define KPF_DIRTY 4 -#define KPF_LRU 5 -#define KPF_ACTIVE 6 -#define KPF_SLAB 7 -#define KPF_WRITEBACK 8 -#define KPF_RECLAIM 9 -#define KPF_BUDDY 10 - -/* [11-20] new additions in 2.6.31 */ -#define KPF_MMAP 11 -#define KPF_ANON 12 -#define KPF_SWAPCACHE 13 -#define KPF_SWAPBACKED 14 -#define KPF_COMPOUND_HEAD 15 -#define KPF_COMPOUND_TAIL 16 -#define KPF_HUGE 17 -#define KPF_UNEVICTABLE 18 -#define KPF_HWPOISON 19 -#define KPF_NOPAGE 20 -#define KPF_KSM 21 -#define KPF_THP 22 - -/* [32-] kernel hacking assistances */ -#define KPF_RESERVED 32 -#define KPF_MLOCKED 33 -#define KPF_MAPPEDTODISK 34 -#define KPF_PRIVATE 35 -#define KPF_PRIVATE_2 36 -#define KPF_OWNER_PRIVATE 37 -#define KPF_ARCH 38 -#define KPF_UNCACHED 39 - -/* [48-] take some arbitrary free slots for expanding overloaded flags - * not part of kernel API - */ -#define KPF_READAHEAD 48 -#define KPF_SLOB_FREE 49 -#define KPF_SLUB_FROZEN 50 -#define KPF_SLUB_DEBUG 51 - -#define KPF_ALL_BITS ((uint64_t)~0ULL) -#define KPF_HACKERS_BITS (0xffffULL << 32) -#define KPF_OVERLOADED_BITS (0xffffULL << 48) -#define BIT(name) (1ULL << KPF_##name) -#define BITS_COMPOUND (BIT(COMPOUND_HEAD) | BIT(COMPOUND_TAIL)) - -static const char *page_flag_names[] = { - [KPF_LOCKED] = "L:locked", - [KPF_ERROR] = "E:error", - [KPF_REFERENCED] = "R:referenced", - [KPF_UPTODATE] = "U:uptodate", - [KPF_DIRTY] = "D:dirty", - [KPF_LRU] = "l:lru", - [KPF_ACTIVE] = "A:active", - [KPF_SLAB] = "S:slab", - [KPF_WRITEBACK] = "W:writeback", - [KPF_RECLAIM] = "I:reclaim", - [KPF_BUDDY] = "B:buddy", - - [KPF_MMAP] = "M:mmap", - [KPF_ANON] = "a:anonymous", - [KPF_SWAPCACHE] = "s:swapcache", - [KPF_SWAPBACKED] = "b:swapbacked", - [KPF_COMPOUND_HEAD] = "H:compound_head", - [KPF_COMPOUND_TAIL] = "T:compound_tail", - [KPF_HUGE] = "G:huge", - [KPF_UNEVICTABLE] = "u:unevictable", - [KPF_HWPOISON] = "X:hwpoison", - [KPF_NOPAGE] = "n:nopage", - [KPF_KSM] = "x:ksm", - [KPF_THP] = "t:thp", - - [KPF_RESERVED] = "r:reserved", - [KPF_MLOCKED] = "m:mlocked", - [KPF_MAPPEDTODISK] = "d:mappedtodisk", - [KPF_PRIVATE] = "P:private", - [KPF_PRIVATE_2] = "p:private_2", - [KPF_OWNER_PRIVATE] = "O:owner_private", - [KPF_ARCH] = "h:arch", - [KPF_UNCACHED] = "c:uncached", - - [KPF_READAHEAD] = "I:readahead", - [KPF_SLOB_FREE] = "P:slob_free", - [KPF_SLUB_FROZEN] = "A:slub_frozen", - [KPF_SLUB_DEBUG] = "E:slub_debug", -}; - - -static const char *debugfs_known_mountpoints[] = { - "/sys/kernel/debug", - "/debug", - 0, -}; - -/* - * data structures - */ - -static int opt_raw; /* for kernel developers */ -static int opt_list; /* list pages (in ranges) */ -static int opt_no_summary; /* don't show summary */ -static pid_t opt_pid; /* process to walk */ - -#define MAX_ADDR_RANGES 1024 -static int nr_addr_ranges; -static unsigned long opt_offset[MAX_ADDR_RANGES]; -static unsigned long opt_size[MAX_ADDR_RANGES]; - -#define MAX_VMAS 10240 -static int nr_vmas; -static unsigned long pg_start[MAX_VMAS]; -static unsigned long pg_end[MAX_VMAS]; - -#define MAX_BIT_FILTERS 64 -static int nr_bit_filters; -static uint64_t opt_mask[MAX_BIT_FILTERS]; -static uint64_t opt_bits[MAX_BIT_FILTERS]; - -static int page_size; - -static int pagemap_fd; -static int kpageflags_fd; - -static int opt_hwpoison; -static int opt_unpoison; - -static char hwpoison_debug_fs[MAX_PATH+1]; -static int hwpoison_inject_fd; -static int hwpoison_forget_fd; - -#define HASH_SHIFT 13 -#define HASH_SIZE (1 << HASH_SHIFT) -#define HASH_MASK (HASH_SIZE - 1) -#define HASH_KEY(flags) (flags & HASH_MASK) - -static unsigned long total_pages; -static unsigned long nr_pages[HASH_SIZE]; -static uint64_t page_flags[HASH_SIZE]; - - -/* - * helper functions - */ - -#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0])) - -#define min_t(type, x, y) ({ \ - type __min1 = (x); \ - type __min2 = (y); \ - __min1 < __min2 ? __min1 : __min2; }) - -#define max_t(type, x, y) ({ \ - type __max1 = (x); \ - type __max2 = (y); \ - __max1 > __max2 ? __max1 : __max2; }) - -static unsigned long pages2mb(unsigned long pages) -{ - return (pages * page_size) >> 20; -} - -static void fatal(const char *x, ...) -{ - va_list ap; - - va_start(ap, x); - vfprintf(stderr, x, ap); - va_end(ap); - exit(EXIT_FAILURE); -} - -static int checked_open(const char *pathname, int flags) -{ - int fd = open(pathname, flags); - - if (fd < 0) { - perror(pathname); - exit(EXIT_FAILURE); - } - - return fd; -} - -/* - * pagemap/kpageflags routines - */ - -static unsigned long do_u64_read(int fd, char *name, - uint64_t *buf, - unsigned long index, - unsigned long count) -{ - long bytes; - - if (index > ULONG_MAX / 8) - fatal("index overflow: %lu\n", index); - - if (lseek(fd, index * 8, SEEK_SET) < 0) { - perror(name); - exit(EXIT_FAILURE); - } - - bytes = read(fd, buf, count * 8); - if (bytes < 0) { - perror(name); - exit(EXIT_FAILURE); - } - if (bytes % 8) - fatal("partial read: %lu bytes\n", bytes); - - return bytes / 8; -} - -static unsigned long kpageflags_read(uint64_t *buf, - unsigned long index, - unsigned long pages) -{ - return do_u64_read(kpageflags_fd, PROC_KPAGEFLAGS, buf, index, pages); -} - -static unsigned long pagemap_read(uint64_t *buf, - unsigned long index, - unsigned long pages) -{ - return do_u64_read(pagemap_fd, "/proc/pid/pagemap", buf, index, pages); -} - -static unsigned long pagemap_pfn(uint64_t val) -{ - unsigned long pfn; - - if (val & PM_PRESENT) - pfn = PM_PFRAME(val); - else - pfn = 0; - - return pfn; -} - - -/* - * page flag names - */ - -static char *page_flag_name(uint64_t flags) -{ - static char buf[65]; - int present; - int i, j; - - for (i = 0, j = 0; i < ARRAY_SIZE(page_flag_names); i++) { - present = (flags >> i) & 1; - if (!page_flag_names[i]) { - if (present) - fatal("unknown flag bit %d\n", i); - continue; - } - buf[j++] = present ? page_flag_names[i][0] : '_'; - } - - return buf; -} - -static char *page_flag_longname(uint64_t flags) -{ - static char buf[1024]; - int i, n; - - for (i = 0, n = 0; i < ARRAY_SIZE(page_flag_names); i++) { - if (!page_flag_names[i]) - continue; - if ((flags >> i) & 1) - n += snprintf(buf + n, sizeof(buf) - n, "%s,", - page_flag_names[i] + 2); - } - if (n) - n--; - buf[n] = '\0'; - - return buf; -} - - -/* - * page list and summary - */ - -static void show_page_range(unsigned long voffset, - unsigned long offset, uint64_t flags) -{ - static uint64_t flags0; - static unsigned long voff; - static unsigned long index; - static unsigned long count; - - if (flags == flags0 && offset == index + count && - (!opt_pid || voffset == voff + count)) { - count++; - return; - } - - if (count) { - if (opt_pid) - printf("%lx\t", voff); - printf("%lx\t%lx\t%s\n", - index, count, page_flag_name(flags0)); - } - - flags0 = flags; - index = offset; - voff = voffset; - count = 1; -} - -static void show_page(unsigned long voffset, - unsigned long offset, uint64_t flags) -{ - if (opt_pid) - printf("%lx\t", voffset); - printf("%lx\t%s\n", offset, page_flag_name(flags)); -} - -static void show_summary(void) -{ - int i; - - printf(" flags\tpage-count MB" - " symbolic-flags\t\t\tlong-symbolic-flags\n"); - - for (i = 0; i < ARRAY_SIZE(nr_pages); i++) { - if (nr_pages[i]) - printf("0x%016llx\t%10lu %8lu %s\t%s\n", - (unsigned long long)page_flags[i], - nr_pages[i], - pages2mb(nr_pages[i]), - page_flag_name(page_flags[i]), - page_flag_longname(page_flags[i])); - } - - printf(" total\t%10lu %8lu\n", - total_pages, pages2mb(total_pages)); -} - - -/* - * page flag filters - */ - -static int bit_mask_ok(uint64_t flags) -{ - int i; - - for (i = 0; i < nr_bit_filters; i++) { - if (opt_bits[i] == KPF_ALL_BITS) { - if ((flags & opt_mask[i]) == 0) - return 0; - } else { - if ((flags & opt_mask[i]) != opt_bits[i]) - return 0; - } - } - - return 1; -} - -static uint64_t expand_overloaded_flags(uint64_t flags) -{ - /* SLOB/SLUB overload several page flags */ - if (flags & BIT(SLAB)) { - if (flags & BIT(PRIVATE)) - flags ^= BIT(PRIVATE) | BIT(SLOB_FREE); - if (flags & BIT(ACTIVE)) - flags ^= BIT(ACTIVE) | BIT(SLUB_FROZEN); - if (flags & BIT(ERROR)) - flags ^= BIT(ERROR) | BIT(SLUB_DEBUG); - } - - /* PG_reclaim is overloaded as PG_readahead in the read path */ - if ((flags & (BIT(RECLAIM) | BIT(WRITEBACK))) == BIT(RECLAIM)) - flags ^= BIT(RECLAIM) | BIT(READAHEAD); - - return flags; -} - -static uint64_t well_known_flags(uint64_t flags) -{ - /* hide flags intended only for kernel hacker */ - flags &= ~KPF_HACKERS_BITS; - - /* hide non-hugeTLB compound pages */ - if ((flags & BITS_COMPOUND) && !(flags & BIT(HUGE))) - flags &= ~BITS_COMPOUND; - - return flags; -} - -static uint64_t kpageflags_flags(uint64_t flags) -{ - flags = expand_overloaded_flags(flags); - - if (!opt_raw) - flags = well_known_flags(flags); - - return flags; -} - -/* verify that a mountpoint is actually a debugfs instance */ -static int debugfs_valid_mountpoint(const char *debugfs) -{ - struct statfs st_fs; - - if (statfs(debugfs, &st_fs) < 0) - return -ENOENT; - else if (st_fs.f_type != (long) DEBUGFS_MAGIC) - return -ENOENT; - - return 0; -} - -/* find the path to the mounted debugfs */ -static const char *debugfs_find_mountpoint(void) -{ - const char **ptr; - char type[100]; - FILE *fp; - - ptr = debugfs_known_mountpoints; - while (*ptr) { - if (debugfs_valid_mountpoint(*ptr) == 0) { - strcpy(hwpoison_debug_fs, *ptr); - return hwpoison_debug_fs; - } - ptr++; - } - - /* give up and parse /proc/mounts */ - fp = fopen("/proc/mounts", "r"); - if (fp == NULL) - perror("Can't open /proc/mounts for read"); - - while (fscanf(fp, "%*s %" - STR(MAX_PATH) - "s %99s %*s %*d %*d\n", - hwpoison_debug_fs, type) == 2) { - if (strcmp(type, "debugfs") == 0) - break; - } - fclose(fp); - - if (strcmp(type, "debugfs") != 0) - return NULL; - - return hwpoison_debug_fs; -} - -/* mount the debugfs somewhere if it's not mounted */ - -static void debugfs_mount(void) -{ - const char **ptr; - - /* see if it's already mounted */ - if (debugfs_find_mountpoint()) - return; - - ptr = debugfs_known_mountpoints; - while (*ptr) { - if (mount(NULL, *ptr, "debugfs", 0, NULL) == 0) { - /* save the mountpoint */ - strcpy(hwpoison_debug_fs, *ptr); - break; - } - ptr++; - } - - if (*ptr == NULL) { - perror("mount debugfs"); - exit(EXIT_FAILURE); - } -} - -/* - * page actions - */ - -static void prepare_hwpoison_fd(void) -{ - char buf[MAX_PATH + 1]; - - debugfs_mount(); - - if (opt_hwpoison && !hwpoison_inject_fd) { - snprintf(buf, MAX_PATH, "%s/hwpoison/corrupt-pfn", - hwpoison_debug_fs); - hwpoison_inject_fd = checked_open(buf, O_WRONLY); - } - - if (opt_unpoison && !hwpoison_forget_fd) { - snprintf(buf, MAX_PATH, "%s/hwpoison/unpoison-pfn", - hwpoison_debug_fs); - hwpoison_forget_fd = checked_open(buf, O_WRONLY); - } -} - -static int hwpoison_page(unsigned long offset) -{ - char buf[100]; - int len; - - len = sprintf(buf, "0x%lx\n", offset); - len = write(hwpoison_inject_fd, buf, len); - if (len < 0) { - perror("hwpoison inject"); - return len; - } - return 0; -} - -static int unpoison_page(unsigned long offset) -{ - char buf[100]; - int len; - - len = sprintf(buf, "0x%lx\n", offset); - len = write(hwpoison_forget_fd, buf, len); - if (len < 0) { - perror("hwpoison forget"); - return len; - } - return 0; -} - -/* - * page frame walker - */ - -static int hash_slot(uint64_t flags) -{ - int k = HASH_KEY(flags); - int i; - - /* Explicitly reserve slot 0 for flags 0: the following logic - * cannot distinguish an unoccupied slot from slot (flags==0). - */ - if (flags == 0) - return 0; - - /* search through the remaining (HASH_SIZE-1) slots */ - for (i = 1; i < ARRAY_SIZE(page_flags); i++, k++) { - if (!k || k >= ARRAY_SIZE(page_flags)) - k = 1; - if (page_flags[k] == 0) { - page_flags[k] = flags; - return k; - } - if (page_flags[k] == flags) - return k; - } - - fatal("hash table full: bump up HASH_SHIFT?\n"); - exit(EXIT_FAILURE); -} - -static void add_page(unsigned long voffset, - unsigned long offset, uint64_t flags) -{ - flags = kpageflags_flags(flags); - - if (!bit_mask_ok(flags)) - return; - - if (opt_hwpoison) - hwpoison_page(offset); - if (opt_unpoison) - unpoison_page(offset); - - if (opt_list == 1) - show_page_range(voffset, offset, flags); - else if (opt_list == 2) - show_page(voffset, offset, flags); - - nr_pages[hash_slot(flags)]++; - total_pages++; -} - -#define KPAGEFLAGS_BATCH (64 << 10) /* 64k pages */ -static void walk_pfn(unsigned long voffset, - unsigned long index, - unsigned long count) -{ - uint64_t buf[KPAGEFLAGS_BATCH]; - unsigned long batch; - long pages; - unsigned long i; - - while (count) { - batch = min_t(unsigned long, count, KPAGEFLAGS_BATCH); - pages = kpageflags_read(buf, index, batch); - if (pages == 0) - break; - - for (i = 0; i < pages; i++) - add_page(voffset + i, index + i, buf[i]); - - index += pages; - count -= pages; - } -} - -#define PAGEMAP_BATCH (64 << 10) -static void walk_vma(unsigned long index, unsigned long count) -{ - uint64_t buf[PAGEMAP_BATCH]; - unsigned long batch; - unsigned long pages; - unsigned long pfn; - unsigned long i; - - while (count) { - batch = min_t(unsigned long, count, PAGEMAP_BATCH); - pages = pagemap_read(buf, index, batch); - if (pages == 0) - break; - - for (i = 0; i < pages; i++) { - pfn = pagemap_pfn(buf[i]); - if (pfn) - walk_pfn(index + i, pfn, 1); - } - - index += pages; - count -= pages; - } -} - -static void walk_task(unsigned long index, unsigned long count) -{ - const unsigned long end = index + count; - unsigned long start; - int i = 0; - - while (index < end) { - - while (pg_end[i] <= index) - if (++i >= nr_vmas) - return; - if (pg_start[i] >= end) - return; - - start = max_t(unsigned long, pg_start[i], index); - index = min_t(unsigned long, pg_end[i], end); - - assert(start < index); - walk_vma(start, index - start); - } -} - -static void add_addr_range(unsigned long offset, unsigned long size) -{ - if (nr_addr_ranges >= MAX_ADDR_RANGES) - fatal("too many addr ranges\n"); - - opt_offset[nr_addr_ranges] = offset; - opt_size[nr_addr_ranges] = min_t(unsigned long, size, ULONG_MAX-offset); - nr_addr_ranges++; -} - -static void walk_addr_ranges(void) -{ - int i; - - kpageflags_fd = checked_open(PROC_KPAGEFLAGS, O_RDONLY); - - if (!nr_addr_ranges) - add_addr_range(0, ULONG_MAX); - - for (i = 0; i < nr_addr_ranges; i++) - if (!opt_pid) - walk_pfn(0, opt_offset[i], opt_size[i]); - else - walk_task(opt_offset[i], opt_size[i]); - - close(kpageflags_fd); -} - - -/* - * user interface - */ - -static const char *page_flag_type(uint64_t flag) -{ - if (flag & KPF_HACKERS_BITS) - return "(r)"; - if (flag & KPF_OVERLOADED_BITS) - return "(o)"; - return " "; -} - -static void usage(void) -{ - int i, j; - - printf( -"page-types [options]\n" -" -r|--raw Raw mode, for kernel developers\n" -" -d|--describe flags Describe flags\n" -" -a|--addr addr-spec Walk a range of pages\n" -" -b|--bits bits-spec Walk pages with specified bits\n" -" -p|--pid pid Walk process address space\n" -#if 0 /* planned features */ -" -f|--file filename Walk file address space\n" -#endif -" -l|--list Show page details in ranges\n" -" -L|--list-each Show page details one by one\n" -" -N|--no-summary Don't show summary info\n" -" -X|--hwpoison hwpoison pages\n" -" -x|--unpoison unpoison pages\n" -" -h|--help Show this usage message\n" -"flags:\n" -" 0x10 bitfield format, e.g.\n" -" anon bit-name, e.g.\n" -" 0x10,anon comma-separated list, e.g.\n" -"addr-spec:\n" -" N one page at offset N (unit: pages)\n" -" N+M pages range from N to N+M-1\n" -" N,M pages range from N to M-1\n" -" N, pages range from N to end\n" -" ,M pages range from 0 to M-1\n" -"bits-spec:\n" -" bit1,bit2 (flags & (bit1|bit2)) != 0\n" -" bit1,bit2=bit1 (flags & (bit1|bit2)) == bit1\n" -" bit1,~bit2 (flags & (bit1|bit2)) == bit1\n" -" =bit1,bit2 flags == (bit1|bit2)\n" -"bit-names:\n" - ); - - for (i = 0, j = 0; i < ARRAY_SIZE(page_flag_names); i++) { - if (!page_flag_names[i]) - continue; - printf("%16s%s", page_flag_names[i] + 2, - page_flag_type(1ULL << i)); - if (++j > 3) { - j = 0; - putchar('\n'); - } - } - printf("\n " - "(r) raw mode bits (o) overloaded bits\n"); -} - -static unsigned long long parse_number(const char *str) -{ - unsigned long long n; - - n = strtoll(str, NULL, 0); - - if (n == 0 && str[0] != '0') - fatal("invalid name or number: %s\n", str); - - return n; -} - -static void parse_pid(const char *str) -{ - FILE *file; - char buf[5000]; - - opt_pid = parse_number(str); - - sprintf(buf, "/proc/%d/pagemap", opt_pid); - pagemap_fd = checked_open(buf, O_RDONLY); - - sprintf(buf, "/proc/%d/maps", opt_pid); - file = fopen(buf, "r"); - if (!file) { - perror(buf); - exit(EXIT_FAILURE); - } - - while (fgets(buf, sizeof(buf), file) != NULL) { - unsigned long vm_start; - unsigned long vm_end; - unsigned long long pgoff; - int major, minor; - char r, w, x, s; - unsigned long ino; - int n; - - n = sscanf(buf, "%lx-%lx %c%c%c%c %llx %x:%x %lu", - &vm_start, - &vm_end, - &r, &w, &x, &s, - &pgoff, - &major, &minor, - &ino); - if (n < 10) { - fprintf(stderr, "unexpected line: %s\n", buf); - continue; - } - pg_start[nr_vmas] = vm_start / page_size; - pg_end[nr_vmas] = vm_end / page_size; - if (++nr_vmas >= MAX_VMAS) { - fprintf(stderr, "too many VMAs\n"); - break; - } - } - fclose(file); -} - -static void parse_file(const char *name) -{ -} - -static void parse_addr_range(const char *optarg) -{ - unsigned long offset; - unsigned long size; - char *p; - - p = strchr(optarg, ','); - if (!p) - p = strchr(optarg, '+'); - - if (p == optarg) { - offset = 0; - size = parse_number(p + 1); - } else if (p) { - offset = parse_number(optarg); - if (p[1] == '\0') - size = ULONG_MAX; - else { - size = parse_number(p + 1); - if (*p == ',') { - if (size < offset) - fatal("invalid range: %lu,%lu\n", - offset, size); - size -= offset; - } - } - } else { - offset = parse_number(optarg); - size = 1; - } - - add_addr_range(offset, size); -} - -static void add_bits_filter(uint64_t mask, uint64_t bits) -{ - if (nr_bit_filters >= MAX_BIT_FILTERS) - fatal("too much bit filters\n"); - - opt_mask[nr_bit_filters] = mask; - opt_bits[nr_bit_filters] = bits; - nr_bit_filters++; -} - -static uint64_t parse_flag_name(const char *str, int len) -{ - int i; - - if (!*str || !len) - return 0; - - if (len <= 8 && !strncmp(str, "compound", len)) - return BITS_COMPOUND; - - for (i = 0; i < ARRAY_SIZE(page_flag_names); i++) { - if (!page_flag_names[i]) - continue; - if (!strncmp(str, page_flag_names[i] + 2, len)) - return 1ULL << i; - } - - return parse_number(str); -} - -static uint64_t parse_flag_names(const char *str, int all) -{ - const char *p = str; - uint64_t flags = 0; - - while (1) { - if (*p == ',' || *p == '=' || *p == '\0') { - if ((*str != '~') || (*str == '~' && all && *++str)) - flags |= parse_flag_name(str, p - str); - if (*p != ',') - break; - str = p + 1; - } - p++; - } - - return flags; -} - -static void parse_bits_mask(const char *optarg) -{ - uint64_t mask; - uint64_t bits; - const char *p; - - p = strchr(optarg, '='); - if (p == optarg) { - mask = KPF_ALL_BITS; - bits = parse_flag_names(p + 1, 0); - } else if (p) { - mask = parse_flag_names(optarg, 0); - bits = parse_flag_names(p + 1, 0); - } else if (strchr(optarg, '~')) { - mask = parse_flag_names(optarg, 1); - bits = parse_flag_names(optarg, 0); - } else { - mask = parse_flag_names(optarg, 0); - bits = KPF_ALL_BITS; - } - - add_bits_filter(mask, bits); -} - -static void describe_flags(const char *optarg) -{ - uint64_t flags = parse_flag_names(optarg, 0); - - printf("0x%016llx\t%s\t%s\n", - (unsigned long long)flags, - page_flag_name(flags), - page_flag_longname(flags)); -} - -static const struct option opts[] = { - { "raw" , 0, NULL, 'r' }, - { "pid" , 1, NULL, 'p' }, - { "file" , 1, NULL, 'f' }, - { "addr" , 1, NULL, 'a' }, - { "bits" , 1, NULL, 'b' }, - { "describe" , 1, NULL, 'd' }, - { "list" , 0, NULL, 'l' }, - { "list-each" , 0, NULL, 'L' }, - { "no-summary", 0, NULL, 'N' }, - { "hwpoison" , 0, NULL, 'X' }, - { "unpoison" , 0, NULL, 'x' }, - { "help" , 0, NULL, 'h' }, - { NULL , 0, NULL, 0 } -}; - -int main(int argc, char *argv[]) -{ - int c; - - page_size = getpagesize(); - - while ((c = getopt_long(argc, argv, - "rp:f:a:b:d:lLNXxh", opts, NULL)) != -1) { - switch (c) { - case 'r': - opt_raw = 1; - break; - case 'p': - parse_pid(optarg); - break; - case 'f': - parse_file(optarg); - break; - case 'a': - parse_addr_range(optarg); - break; - case 'b': - parse_bits_mask(optarg); - break; - case 'd': - describe_flags(optarg); - exit(0); - case 'l': - opt_list = 1; - break; - case 'L': - opt_list = 2; - break; - case 'N': - opt_no_summary = 1; - break; - case 'X': - opt_hwpoison = 1; - prepare_hwpoison_fd(); - break; - case 'x': - opt_unpoison = 1; - prepare_hwpoison_fd(); - break; - case 'h': - usage(); - exit(0); - default: - usage(); - exit(1); - } - } - - if (opt_list && opt_pid) - printf("voffset\t"); - if (opt_list == 1) - printf("offset\tlen\tflags\n"); - if (opt_list == 2) - printf("offset\tflags\n"); - - walk_addr_ranges(); - - if (opt_list == 1) - show_page_range(0, 0, 0); /* drain the buffer */ - - if (opt_no_summary) - return 0; - - if (opt_list) - printf("\n\n"); - - show_summary(); - - return 0; -} diff --git a/Documentation/watchdog/00-INDEX b/Documentation/watchdog/00-INDEX deleted file mode 100644 index fc9082a..0000000 --- a/Documentation/watchdog/00-INDEX +++ /dev/null @@ -1,19 +0,0 @@ -00-INDEX - - this file. -convert_drivers_to_kernel_api.txt - - how-to for converting old watchdog drivers to the new kernel API. -hpwdt.txt - - information on the HP iLO2 NMI watchdog -pcwd-watchdog.txt - - documentation for Berkshire Products PC Watchdog ISA cards. -src/ - - directory holding watchdog related example programs. -watchdog-api.txt - - description of the Linux Watchdog driver API. -watchdog-kernel-api.txt - - description of the Linux WatchDog Timer Driver Core kernel API. -watchdog-parameters.txt - - information on driver parameters (for drivers other than - the ones that have driver-specific files here) -wdt.txt - - description of the Watchdog Timer Interfaces for Linux. diff --git a/Documentation/watchdog/convert_drivers_to_kernel_api.txt b/Documentation/watchdog/convert_drivers_to_kernel_api.txt index be8119b..271b885 100644 --- a/Documentation/watchdog/convert_drivers_to_kernel_api.txt +++ b/Documentation/watchdog/convert_drivers_to_kernel_api.txt @@ -59,6 +59,10 @@ Here is a overview of the functions and probably needed actions: WDIOC_GETTIMEOUT: No preparations needed + WDIOC_GETTIMELEFT: + It needs get_timeleft() callback to be defined. Otherwise it + will return EOPNOTSUPP + Other IOCTLs can be served using the ioctl-callback. Note that this is mainly intended for porting old drivers; new drivers should not invent private IOCTLs. Private IOCTLs are processed first. When the callback returns with diff --git a/Documentation/watchdog/watchdog-kernel-api.txt b/Documentation/watchdog/watchdog-kernel-api.txt index 9e16246..227f6cd 100644 --- a/Documentation/watchdog/watchdog-kernel-api.txt +++ b/Documentation/watchdog/watchdog-kernel-api.txt @@ -1,6 +1,6 @@ The Linux WatchDog Timer Driver Core kernel API. =============================================== -Last reviewed: 29-Nov-2011 +Last reviewed: 16-Mar-2012 Wim Van Sebroeck <wim@iguana.be> @@ -77,6 +77,7 @@ struct watchdog_ops { int (*ping)(struct watchdog_device *); unsigned int (*status)(struct watchdog_device *); int (*set_timeout)(struct watchdog_device *, unsigned int); + unsigned int (*get_timeleft)(struct watchdog_device *); long (*ioctl)(struct watchdog_device *, unsigned int, unsigned long); }; @@ -117,11 +118,13 @@ they are supported. These optional routines/operations are: status of the device is reported with watchdog WDIOF_* status flags/bits. * set_timeout: this routine checks and changes the timeout of the watchdog timer device. It returns 0 on success, -EINVAL for "parameter out of range" - and -EIO for "could not write value to the watchdog". On success the timeout - value of the watchdog_device will be changed to the value that was just used - to re-program the watchdog timer device. + and -EIO for "could not write value to the watchdog". On success this + routine should set the timeout value of the watchdog_device to the + achieved timeout value (which may be different from the requested one + because the watchdog does not necessarily has a 1 second resolution). (Note: the WDIOF_SETTIMEOUT needs to be set in the options field of the watchdog's info structure). +* get_timeleft: this routines returns the time that's left before a reset. * ioctl: if this routine is present then it will be called first before we do our own internal ioctl call handling. This routine should return -ENOIOCTLCMD if a command is not supported. The parameters that are passed to the ioctl |