diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2009-01-09 19:52:14 (GMT) |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-01-09 19:52:14 (GMT) |
commit | d9e8a3a5b8298a3c814ed37ac5756e6f67b6be41 (patch) | |
tree | ffa1cf8b367b3f32155f6336d7b86b781a368019 | |
parent | 2150edc6c5cf00f7adb54538b9ea2a3e9cedca3f (diff) | |
parent | b9bdcbba010c2e49c8f837ea7a49fe006b636f41 (diff) | |
download | linux-d9e8a3a5b8298a3c814ed37ac5756e6f67b6be41.tar.xz |
Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx: (22 commits)
ioat: fix self test for multi-channel case
dmaengine: bump initcall level to arch_initcall
dmaengine: advertise all channels on a device to dma_filter_fn
dmaengine: use idr for registering dma device numbers
dmaengine: add a release for dma class devices and dependent infrastructure
ioat: do not perform removal actions at shutdown
iop-adma: enable module removal
iop-adma: kill debug BUG_ON
iop-adma: let devm do its job, don't duplicate free
dmaengine: kill enum dma_state_client
dmaengine: remove 'bigref' infrastructure
dmaengine: kill struct dma_client and supporting infrastructure
dmaengine: replace dma_async_client_register with dmaengine_get
atmel-mci: convert to dma_request_channel and down-level dma_slave
dmatest: convert to dma_request_channel
dmaengine: introduce dma_request_channel and private channels
net_dma: convert to dma_find_channel
dmaengine: provide a common 'issue_pending_all' implementation
dmaengine: centralize channel allocation, introduce dma_find_channel
dmaengine: up-level reference counting to the module level
...
-rw-r--r-- | Documentation/crypto/async-tx-api.txt | 96 | ||||
-rw-r--r-- | Documentation/dmaengine.txt | 1 | ||||
-rw-r--r-- | arch/avr32/mach-at32ap/at32ap700x.c | 15 | ||||
-rw-r--r-- | crypto/async_tx/async_tx.c | 350 | ||||
-rw-r--r-- | drivers/dca/dca-core.c | 2 | ||||
-rw-r--r-- | drivers/dma/Kconfig | 2 | ||||
-rw-r--r-- | drivers/dma/dmaengine.c | 778 | ||||
-rw-r--r-- | drivers/dma/dmatest.c | 129 | ||||
-rw-r--r-- | drivers/dma/dw_dmac.c | 119 | ||||
-rw-r--r-- | drivers/dma/fsldma.c | 5 | ||||
-rw-r--r-- | drivers/dma/ioat.c | 92 | ||||
-rw-r--r-- | drivers/dma/ioat_dma.c | 18 | ||||
-rw-r--r-- | drivers/dma/iop-adma.c | 30 | ||||
-rw-r--r-- | drivers/dma/mv_xor.c | 11 | ||||
-rw-r--r-- | drivers/mmc/host/atmel-mci.c | 103 | ||||
-rw-r--r-- | include/linux/async_tx.h | 17 | ||||
-rw-r--r-- | include/linux/atmel-mci.h | 6 | ||||
-rw-r--r-- | include/linux/dmaengine.h | 181 | ||||
-rw-r--r-- | include/linux/dw_dmac.h | 31 | ||||
-rw-r--r-- | include/linux/netdevice.h | 3 | ||||
-rw-r--r-- | include/net/netdma.h | 11 | ||||
-rw-r--r-- | net/core/dev.c | 149 | ||||
-rw-r--r-- | net/ipv4/tcp.c | 5 | ||||
-rw-r--r-- | net/ipv4/tcp_input.c | 2 | ||||
-rw-r--r-- | net/ipv4/tcp_ipv4.c | 2 | ||||
-rw-r--r-- | net/ipv6/tcp_ipv6.c | 2 |
26 files changed, 900 insertions, 1260 deletions
diff --git a/Documentation/crypto/async-tx-api.txt b/Documentation/crypto/async-tx-api.txt index c1e9545..9f59fcb 100644 --- a/Documentation/crypto/async-tx-api.txt +++ b/Documentation/crypto/async-tx-api.txt @@ -13,9 +13,9 @@ 3.6 Constraints 3.7 Example -4 DRIVER DEVELOPER NOTES +4 DMAENGINE DRIVER DEVELOPER NOTES 4.1 Conformance points -4.2 "My application needs finer control of hardware channels" +4.2 "My application needs exclusive control of hardware channels" 5 SOURCE @@ -150,6 +150,7 @@ ops_run_* and ops_complete_* routines in drivers/md/raid5.c for more implementation examples. 4 DRIVER DEVELOPMENT NOTES + 4.1 Conformance points: There are a few conformance points required in dmaengine drivers to accommodate assumptions made by applications using the async_tx API: @@ -158,58 +159,49 @@ accommodate assumptions made by applications using the async_tx API: 3/ Use async_tx_run_dependencies() in the descriptor clean up path to handle submission of dependent operations -4.2 "My application needs finer control of hardware channels" -This requirement seems to arise from cases where a DMA engine driver is -trying to support device-to-memory DMA. The dmaengine and async_tx -implementations were designed for offloading memory-to-memory -operations; however, there are some capabilities of the dmaengine layer -that can be used for platform-specific channel management. -Platform-specific constraints can be handled by registering the -application as a 'dma_client' and implementing a 'dma_event_callback' to -apply a filter to the available channels in the system. Before showing -how to implement a custom dma_event callback some background of -dmaengine's client support is required. - -The following routines in dmaengine support multiple clients requesting -use of a channel: -- dma_async_client_register(struct dma_client *client) -- dma_async_client_chan_request(struct dma_client *client) - -dma_async_client_register takes a pointer to an initialized dma_client -structure. It expects that the 'event_callback' and 'cap_mask' fields -are already initialized. - -dma_async_client_chan_request triggers dmaengine to notify the client of -all channels that satisfy the capability mask. It is up to the client's -event_callback routine to track how many channels the client needs and -how many it is currently using. The dma_event_callback routine returns a -dma_state_client code to let dmaengine know the status of the -allocation. - -Below is the example of how to extend this functionality for -platform-specific filtering of the available channels beyond the -standard capability mask: - -static enum dma_state_client -my_dma_client_callback(struct dma_client *client, - struct dma_chan *chan, enum dma_state state) -{ - struct dma_device *dma_dev; - struct my_platform_specific_dma *plat_dma_dev; - - dma_dev = chan->device; - plat_dma_dev = container_of(dma_dev, - struct my_platform_specific_dma, - dma_dev); - - if (!plat_dma_dev->platform_specific_capability) - return DMA_DUP; - - . . . -} +4.2 "My application needs exclusive control of hardware channels" +Primarily this requirement arises from cases where a DMA engine driver +is being used to support device-to-memory operations. A channel that is +performing these operations cannot, for many platform specific reasons, +be shared. For these cases the dma_request_channel() interface is +provided. + +The interface is: +struct dma_chan *dma_request_channel(dma_cap_mask_t mask, + dma_filter_fn filter_fn, + void *filter_param); + +Where dma_filter_fn is defined as: +typedef bool (*dma_filter_fn)(struct dma_chan *chan, void *filter_param); + +When the optional 'filter_fn' parameter is set to NULL +dma_request_channel simply returns the first channel that satisfies the +capability mask. Otherwise, when the mask parameter is insufficient for +specifying the necessary channel, the filter_fn routine can be used to +disposition the available channels in the system. The filter_fn routine +is called once for each free channel in the system. Upon seeing a +suitable channel filter_fn returns DMA_ACK which flags that channel to +be the return value from dma_request_channel. A channel allocated via +this interface is exclusive to the caller, until dma_release_channel() +is called. + +The DMA_PRIVATE capability flag is used to tag dma devices that should +not be used by the general-purpose allocator. It can be set at +initialization time if it is known that a channel will always be +private. Alternatively, it is set when dma_request_channel() finds an +unused "public" channel. + +A couple caveats to note when implementing a driver and consumer: +1/ Once a channel has been privately allocated it will no longer be + considered by the general-purpose allocator even after a call to + dma_release_channel(). +2/ Since capabilities are specified at the device level a dma_device + with multiple channels will either have all channels public, or all + channels private. 5 SOURCE -include/linux/dmaengine.h: core header file for DMA drivers and clients + +include/linux/dmaengine.h: core header file for DMA drivers and api users drivers/dma/dmaengine.c: offload engine channel management routines drivers/dma/: location for offload engine drivers include/linux/async_tx.h: core header file for the async_tx api diff --git a/Documentation/dmaengine.txt b/Documentation/dmaengine.txt new file mode 100644 index 0000000..0c1c2f6 --- /dev/null +++ b/Documentation/dmaengine.txt @@ -0,0 +1 @@ +See Documentation/crypto/async-tx-api.txt diff --git a/arch/avr32/mach-at32ap/at32ap700x.c b/arch/avr32/mach-at32ap/at32ap700x.c index ea7bc1e..3fbfd1e 100644 --- a/arch/avr32/mach-at32ap/at32ap700x.c +++ b/arch/avr32/mach-at32ap/at32ap700x.c @@ -1305,7 +1305,7 @@ struct platform_device *__init at32_add_device_mci(unsigned int id, struct mci_platform_data *data) { struct platform_device *pdev; - struct dw_dma_slave *dws; + struct dw_dma_slave *dws = &data->dma_slave; u32 pioa_mask; u32 piob_mask; @@ -1324,22 +1324,13 @@ at32_add_device_mci(unsigned int id, struct mci_platform_data *data) ARRAY_SIZE(atmel_mci0_resource))) goto fail; - if (data->dma_slave) - dws = kmemdup(to_dw_dma_slave(data->dma_slave), - sizeof(struct dw_dma_slave), GFP_KERNEL); - else - dws = kzalloc(sizeof(struct dw_dma_slave), GFP_KERNEL); - - dws->slave.dev = &pdev->dev; - dws->slave.dma_dev = &dw_dmac0_device.dev; - dws->slave.reg_width = DMA_SLAVE_WIDTH_32BIT; + dws->dma_dev = &dw_dmac0_device.dev; + dws->reg_width = DW_DMA_SLAVE_WIDTH_32BIT; dws->cfg_hi = (DWC_CFGH_SRC_PER(0) | DWC_CFGH_DST_PER(1)); dws->cfg_lo &= ~(DWC_CFGL_HS_DST_POL | DWC_CFGL_HS_SRC_POL); - data->dma_slave = &dws->slave; - if (platform_device_add_data(pdev, data, sizeof(struct mci_platform_data))) goto fail; diff --git a/crypto/async_tx/async_tx.c b/crypto/async_tx/async_tx.c index dcbf1be..f21147f 100644 --- a/crypto/async_tx/async_tx.c +++ b/crypto/async_tx/async_tx.c @@ -28,351 +28,18 @@ #include <linux/async_tx.h> #ifdef CONFIG_DMA_ENGINE -static enum dma_state_client -dma_channel_add_remove(struct dma_client *client, - struct dma_chan *chan, enum dma_state state); - -static struct dma_client async_tx_dma = { - .event_callback = dma_channel_add_remove, - /* .cap_mask == 0 defaults to all channels */ -}; - -/** - * dma_cap_mask_all - enable iteration over all operation types - */ -static dma_cap_mask_t dma_cap_mask_all; - -/** - * chan_ref_percpu - tracks channel allocations per core/opertion - */ -struct chan_ref_percpu { - struct dma_chan_ref *ref; -}; - -static int channel_table_initialized; -static struct chan_ref_percpu *channel_table[DMA_TX_TYPE_END]; - -/** - * async_tx_lock - protect modification of async_tx_master_list and serialize - * rebalance operations - */ -static spinlock_t async_tx_lock; - -static LIST_HEAD(async_tx_master_list); - -/* async_tx_issue_pending_all - start all transactions on all channels */ -void async_tx_issue_pending_all(void) -{ - struct dma_chan_ref *ref; - - rcu_read_lock(); - list_for_each_entry_rcu(ref, &async_tx_master_list, node) - ref->chan->device->device_issue_pending(ref->chan); - rcu_read_unlock(); -} -EXPORT_SYMBOL_GPL(async_tx_issue_pending_all); - -/* dma_wait_for_async_tx - spin wait for a transcation to complete - * @tx: transaction to wait on - */ -enum dma_status -dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx) -{ - enum dma_status status; - struct dma_async_tx_descriptor *iter; - struct dma_async_tx_descriptor *parent; - - if (!tx) - return DMA_SUCCESS; - - /* poll through the dependency chain, return when tx is complete */ - do { - iter = tx; - - /* find the root of the unsubmitted dependency chain */ - do { - parent = iter->parent; - if (!parent) - break; - else - iter = parent; - } while (parent); - - /* there is a small window for ->parent == NULL and - * ->cookie == -EBUSY - */ - while (iter->cookie == -EBUSY) - cpu_relax(); - - status = dma_sync_wait(iter->chan, iter->cookie); - } while (status == DMA_IN_PROGRESS || (iter != tx)); - - return status; -} -EXPORT_SYMBOL_GPL(dma_wait_for_async_tx); - -/* async_tx_run_dependencies - helper routine for dma drivers to process - * (start) dependent operations on their target channel - * @tx: transaction with dependencies - */ -void async_tx_run_dependencies(struct dma_async_tx_descriptor *tx) -{ - struct dma_async_tx_descriptor *dep = tx->next; - struct dma_async_tx_descriptor *dep_next; - struct dma_chan *chan; - - if (!dep) - return; - - chan = dep->chan; - - /* keep submitting up until a channel switch is detected - * in that case we will be called again as a result of - * processing the interrupt from async_tx_channel_switch - */ - for (; dep; dep = dep_next) { - spin_lock_bh(&dep->lock); - dep->parent = NULL; - dep_next = dep->next; - if (dep_next && dep_next->chan == chan) - dep->next = NULL; /* ->next will be submitted */ - else - dep_next = NULL; /* submit current dep and terminate */ - spin_unlock_bh(&dep->lock); - - dep->tx_submit(dep); - } - - chan->device->device_issue_pending(chan); -} -EXPORT_SYMBOL_GPL(async_tx_run_dependencies); - -static void -free_dma_chan_ref(struct rcu_head *rcu) -{ - struct dma_chan_ref *ref; - ref = container_of(rcu, struct dma_chan_ref, rcu); - kfree(ref); -} - -static void -init_dma_chan_ref(struct dma_chan_ref *ref, struct dma_chan *chan) -{ - INIT_LIST_HEAD(&ref->node); - INIT_RCU_HEAD(&ref->rcu); - ref->chan = chan; - atomic_set(&ref->count, 0); -} - -/** - * get_chan_ref_by_cap - returns the nth channel of the given capability - * defaults to returning the channel with the desired capability and the - * lowest reference count if the index can not be satisfied - * @cap: capability to match - * @index: nth channel desired, passing -1 has the effect of forcing the - * default return value - */ -static struct dma_chan_ref * -get_chan_ref_by_cap(enum dma_transaction_type cap, int index) -{ - struct dma_chan_ref *ret_ref = NULL, *min_ref = NULL, *ref; - - rcu_read_lock(); - list_for_each_entry_rcu(ref, &async_tx_master_list, node) - if (dma_has_cap(cap, ref->chan->device->cap_mask)) { - if (!min_ref) - min_ref = ref; - else if (atomic_read(&ref->count) < - atomic_read(&min_ref->count)) - min_ref = ref; - - if (index-- == 0) { - ret_ref = ref; - break; - } - } - rcu_read_unlock(); - - if (!ret_ref) - ret_ref = min_ref; - - if (ret_ref) - atomic_inc(&ret_ref->count); - - return ret_ref; -} - -/** - * async_tx_rebalance - redistribute the available channels, optimize - * for cpu isolation in the SMP case, and opertaion isolation in the - * uniprocessor case - */ -static void async_tx_rebalance(void) -{ - int cpu, cap, cpu_idx = 0; - unsigned long flags; - - if (!channel_table_initialized) - return; - - spin_lock_irqsave(&async_tx_lock, flags); - - /* undo the last distribution */ - for_each_dma_cap_mask(cap, dma_cap_mask_all) - for_each_possible_cpu(cpu) { - struct dma_chan_ref *ref = - per_cpu_ptr(channel_table[cap], cpu)->ref; - if (ref) { - atomic_set(&ref->count, 0); - per_cpu_ptr(channel_table[cap], cpu)->ref = - NULL; - } - } - - for_each_dma_cap_mask(cap, dma_cap_mask_all) - for_each_online_cpu(cpu) { - struct dma_chan_ref *new; - if (NR_CPUS > 1) - new = get_chan_ref_by_cap(cap, cpu_idx++); - else - new = get_chan_ref_by_cap(cap, -1); - - per_cpu_ptr(channel_table[cap], cpu)->ref = new; - } - - spin_unlock_irqrestore(&async_tx_lock, flags); -} - -static enum dma_state_client -dma_channel_add_remove(struct dma_client *client, - struct dma_chan *chan, enum dma_state state) -{ - unsigned long found, flags; - struct dma_chan_ref *master_ref, *ref; - enum dma_state_client ack = DMA_DUP; /* default: take no action */ - - switch (state) { - case DMA_RESOURCE_AVAILABLE: - found = 0; - rcu_read_lock(); - list_for_each_entry_rcu(ref, &async_tx_master_list, node) - if (ref->chan == chan) { - found = 1; - break; - } - rcu_read_unlock(); - - pr_debug("async_tx: dma resource available [%s]\n", - found ? "old" : "new"); - - if (!found) - ack = DMA_ACK; - else - break; - - /* add the channel to the generic management list */ - master_ref = kmalloc(sizeof(*master_ref), GFP_KERNEL); - if (master_ref) { - /* keep a reference until async_tx is unloaded */ - dma_chan_get(chan); - init_dma_chan_ref(master_ref, chan); - spin_lock_irqsave(&async_tx_lock, flags); - list_add_tail_rcu(&master_ref->node, - &async_tx_master_list); - spin_unlock_irqrestore(&async_tx_lock, - flags); - } else { - printk(KERN_WARNING "async_tx: unable to create" - " new master entry in response to" - " a DMA_RESOURCE_ADDED event" - " (-ENOMEM)\n"); - return 0; - } - - async_tx_rebalance(); - break; - case DMA_RESOURCE_REMOVED: - found = 0; - spin_lock_irqsave(&async_tx_lock, flags); - list_for_each_entry(ref, &async_tx_master_list, node) - if (ref->chan == chan) { - /* permit backing devices to go away */ - dma_chan_put(ref->chan); - list_del_rcu(&ref->node); - call_rcu(&ref->rcu, free_dma_chan_ref); - found = 1; - break; - } - spin_unlock_irqrestore(&async_tx_lock, flags); - - pr_debug("async_tx: dma resource removed [%s]\n", - found ? "ours" : "not ours"); - - if (found) - ack = DMA_ACK; - else - break; - - async_tx_rebalance(); - break; - case DMA_RESOURCE_SUSPEND: - case DMA_RESOURCE_RESUME: - printk(KERN_WARNING "async_tx: does not support dma channel" - " suspend/resume\n"); - break; - default: - BUG(); - } - - return ack; -} - -static int __init -async_tx_init(void) +static int __init async_tx_init(void) { - enum dma_transaction_type cap; - - spin_lock_init(&async_tx_lock); - bitmap_fill(dma_cap_mask_all.bits, DMA_TX_TYPE_END); - - /* an interrupt will never be an explicit operation type. - * clearing this bit prevents allocation to a slot in 'channel_table' - */ - clear_bit(DMA_INTERRUPT, dma_cap_mask_all.bits); - - for_each_dma_cap_mask(cap, dma_cap_mask_all) { - channel_table[cap] = alloc_percpu(struct chan_ref_percpu); - if (!channel_table[cap]) - goto err; - } - - channel_table_initialized = 1; - dma_async_client_register(&async_tx_dma); - dma_async_client_chan_request(&async_tx_dma); + dmaengine_get(); printk(KERN_INFO "async_tx: api initialized (async)\n"); return 0; -err: - printk(KERN_ERR "async_tx: initialization failure\n"); - - while (--cap >= 0) - free_percpu(channel_table[cap]); - - return 1; } static void __exit async_tx_exit(void) { - enum dma_transaction_type cap; - - channel_table_initialized = 0; - - for_each_dma_cap_mask(cap, dma_cap_mask_all) - if (channel_table[cap]) - free_percpu(channel_table[cap]); - - dma_async_client_unregister(&async_tx_dma); + dmaengine_put(); } /** @@ -387,16 +54,9 @@ __async_tx_find_channel(struct dma_async_tx_descriptor *depend_tx, { /* see if we can keep the chain on one channel */ if (depend_tx && - dma_has_cap(tx_type, depend_tx->chan->device->cap_mask)) + dma_has_cap(tx_type, depend_tx->chan->device->cap_mask)) return depend_tx->chan; - else if (likely(channel_table_initialized)) { - struct dma_chan_ref *ref; - int cpu = get_cpu(); - ref = per_cpu_ptr(channel_table[tx_type], cpu)->ref; - put_cpu(); - return ref ? ref->chan : NULL; - } else - return NULL; + return dma_find_channel(tx_type); } EXPORT_SYMBOL_GPL(__async_tx_find_channel); #else diff --git a/drivers/dca/dca-core.c b/drivers/dca/dca-core.c index d883e1b..5543384 100644 --- a/drivers/dca/dca-core.c +++ b/drivers/dca/dca-core.c @@ -270,6 +270,6 @@ static void __exit dca_exit(void) dca_sysfs_exit(); } -subsys_initcall(dca_init); +arch_initcall(dca_init); module_exit(dca_exit); diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig index 904e575..e34b064 100644 --- a/drivers/dma/Kconfig +++ b/drivers/dma/Kconfig @@ -33,7 +33,6 @@ config INTEL_IOATDMA config INTEL_IOP_ADMA tristate "Intel IOP ADMA support" depends on ARCH_IOP32X || ARCH_IOP33X || ARCH_IOP13XX - select ASYNC_CORE select DMA_ENGINE help Enable support for the Intel(R) IOP Series RAID engines. @@ -59,7 +58,6 @@ config FSL_DMA config MV_XOR bool "Marvell XOR engine support" depends on PLAT_ORION - select ASYNC_CORE select DMA_ENGINE ---help--- Enable support for the Marvell XOR engine. diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c index 6579965..403dbe7 100644 --- a/drivers/dma/dmaengine.c +++ b/drivers/dma/dmaengine.c @@ -31,32 +31,18 @@ * * LOCKING: * - * The subsystem keeps two global lists, dma_device_list and dma_client_list. - * Both of these are protected by a mutex, dma_list_mutex. + * The subsystem keeps a global list of dma_device structs it is protected by a + * mutex, dma_list_mutex. + * + * A subsystem can get access to a channel by calling dmaengine_get() followed + * by dma_find_channel(), or if it has need for an exclusive channel it can call + * dma_request_channel(). Once a channel is allocated a reference is taken + * against its corresponding driver to disable removal. * * Each device has a channels list, which runs unlocked but is never modified * once the device is registered, it's just setup by the driver. * - * Each client is responsible for keeping track of the channels it uses. See - * the definition of dma_event_callback in dmaengine.h. - * - * Each device has a kref, which is initialized to 1 when the device is - * registered. A kref_get is done for each device registered. When the - * device is released, the corresponding kref_put is done in the release - * method. Every time one of the device's channels is allocated to a client, - * a kref_get occurs. When the channel is freed, the corresponding kref_put - * happens. The device's release function does a completion, so - * unregister_device does a remove event, device_unregister, a kref_put - * for the first reference, then waits on the completion for all other - * references to finish. - * - * Each channel has an open-coded implementation of Rusty Russell's "bigref," - * with a kref and a per_cpu local_t. A dma_chan_get is called when a client - * signals that it wants to use a channel, and dma_chan_put is called when - * a channel is removed or a client using it is unregistered. A client can - * take extra references per outstanding transaction, as is the case with - * the NET DMA client. The release function does a kref_put on the device. - * -ChrisL, DanW + * See Documentation/dmaengine.txt for more details */ #include <linux/init.h> @@ -70,54 +56,85 @@ #include <linux/rcupdate.h> #include <linux/mutex.h> #include <linux/jiffies.h> +#include <linux/rculist.h> +#include <linux/idr.h> static DEFINE_MUTEX(dma_list_mutex); static LIST_HEAD(dma_device_list); -static LIST_HEAD(dma_client_list); +static long dmaengine_ref_count; +static struct idr dma_idr; /* --- sysfs implementation --- */ +/** + * dev_to_dma_chan - convert a device pointer to the its sysfs container object + * @dev - device node + * + * Must be called under dma_list_mutex + */ +static struct dma_chan *dev_to_dma_chan(struct device *dev) +{ + struct dma_chan_dev *chan_dev; + + chan_dev = container_of(dev, typeof(*chan_dev), device); + return chan_dev->chan; +} + static ssize_t show_memcpy_count(struct device *dev, struct device_attribute *attr, char *buf) { - struct dma_chan *chan = to_dma_chan(dev); + struct dma_chan *chan; unsigned long count = 0; int i; + int err; - for_each_possible_cpu(i) - count += per_cpu_ptr(chan->local, i)->memcpy_count; + mutex_lock(&dma_list_mutex); + chan = dev_to_dma_chan(dev); + if (chan) { + for_each_possible_cpu(i) + count += per_cpu_ptr(chan->local, i)->memcpy_count; + err = sprintf(buf, "%lu\n", count); + } else + err = -ENODEV; + mutex_unlock(&dma_list_mutex); - return sprintf(buf, "%lu\n", count); + return err; } static ssize_t show_bytes_transferred(struct device *dev, struct device_attribute *attr, char *buf) { - struct dma_chan *chan = to_dma_chan(dev); + struct dma_chan *chan; unsigned long count = 0; int i; + int err; - for_each_possible_cpu(i) - count += per_cpu_ptr(chan->local, i)->bytes_transferred; + mutex_lock(&dma_list_mutex); + chan = dev_to_dma_chan(dev); + if (chan) { + for_each_possible_cpu(i) + count += per_cpu_ptr(chan->local, i)->bytes_transferred; + err = sprintf(buf, "%lu\n", count); + } else + err = -ENODEV; + mutex_unlock(&dma_list_mutex); - return sprintf(buf, "%lu\n", count); + return err; } static ssize_t show_in_use(struct device *dev, struct device_attribute *attr, char *buf) { - struct dma_chan *chan = to_dma_chan(dev); - int in_use = 0; - - if (unlikely(chan->slow_ref) && - atomic_read(&chan->refcount.refcount) > 1) - in_use = 1; - else { - if (local_read(&(per_cpu_ptr(chan->local, - get_cpu())->refcount)) > 0) - in_use = 1; - put_cpu(); - } + struct dma_chan *chan; + int err; - return sprintf(buf, "%d\n", in_use); + mutex_lock(&dma_list_mutex); + chan = dev_to_dma_chan(dev); + if (chan) + err = sprintf(buf, "%d\n", chan->client_count); + else + err = -ENODEV; + mutex_unlock(&dma_list_mutex); + + return err; } static struct device_attribute dma_attrs[] = { @@ -127,76 +144,110 @@ static struct device_attribute dma_attrs[] = { __ATTR_NULL }; -static void dma_async_device_cleanup(struct kref *kref); - -static void dma_dev_release(struct device *dev) +static void chan_dev_release(struct device *dev) { - struct dma_chan *chan = to_dma_chan(dev); - kref_put(&chan->device->refcount, dma_async_device_cleanup); + struct dma_chan_dev *chan_dev; + + chan_dev = container_of(dev, typeof(*chan_dev), device); + if (atomic_dec_and_test(chan_dev->idr_ref)) { + mutex_lock(&dma_list_mutex); + idr_remove(&dma_idr, chan_dev->dev_id); + mutex_unlock(&dma_list_mutex); + kfree(chan_dev->idr_ref); + } + kfree(chan_dev); } static struct class dma_devclass = { .name = "dma", .dev_attrs = dma_attrs, - .dev_release = dma_dev_release, + .dev_release = chan_dev_release, }; /* --- client and device registration --- */ -#define dma_chan_satisfies_mask(chan, mask) \ - __dma_chan_satisfies_mask((chan), &(mask)) +#define dma_device_satisfies_mask(device, mask) \ + __dma_device_satisfies_mask((device), &(mask)) static int -__dma_chan_satisfies_mask(struct dma_chan *chan, dma_cap_mask_t *want) +__dma_device_satisfies_mask(struct dma_device *device, dma_cap_mask_t *want) { dma_cap_mask_t has; - bitmap_and(has.bits, want->bits, chan->device->cap_mask.bits, + bitmap_and(has.bits, want->bits, device->cap_mask.bits, DMA_TX_TYPE_END); return bitmap_equal(want->bits, has.bits, DMA_TX_TYPE_END); } +static struct module *dma_chan_to_owner(struct dma_chan *chan) +{ + return chan->device->dev->driver->owner; +} + /** - * dma_client_chan_alloc - try to allocate channels to a client - * @client: &dma_client + * balance_ref_count - catch up the channel reference count + * @chan - channel to balance ->client_count versus dmaengine_ref_count * - * Called with dma_list_mutex held. + * balance_ref_count must be called under dma_list_mutex */ -static void dma_client_chan_alloc(struct dma_client *client) +static void balance_ref_count(struct dma_chan *chan) { - struct dma_device *device; - struct dma_chan *chan; - int desc; /* allocated descriptor count */ - enum dma_state_client ack; + struct module *owner = dma_chan_to_owner(chan); - /* Find a channel */ - list_for_each_entry(device, &dma_device_list, global_node) { - /* Does the client require a specific DMA controller? */ - if (client->slave && client->slave->dma_dev - && client->slave->dma_dev != device->dev) - continue; + while (chan->client_count < dmaengine_ref_count) { + __module_get(owner); + chan->client_count++; + } +} - list_for_each_entry(chan, &device->channels, device_node) { - if (!dma_chan_satisfies_mask(chan, client->cap_mask)) - continue; +/** + * dma_chan_get - try to grab a dma channel's parent driver module + * @chan - channel to grab + * + * Must be called under dma_list_mutex + */ +static int dma_chan_get(struct dma_chan *chan) +{ + int err = -ENODEV; + struct module *owner = dma_chan_to_owner(chan); + + if (chan->client_count) { + __module_get(owner); + err = 0; + } else if (try_module_get(owner)) + err = 0; + + if (err == 0) + chan->client_count++; + + /* allocate upon first client reference */ + if (chan->client_count == 1 && err == 0) { + int desc_cnt = chan->device->device_alloc_chan_resources(chan); + + if (desc_cnt < 0) { + err = desc_cnt; + chan->client_count = 0; + module_put(owner); + } else if (!dma_has_cap(DMA_PRIVATE, chan->device->cap_mask)) + balance_ref_count(chan); + } - desc = chan->device->device_alloc_chan_resources( - chan, client); - if (desc >= 0) { - ack = client->event_callback(client, - chan, - DMA_RESOURCE_AVAILABLE); + return err; +} - /* we are done once this client rejects - * an available resource - */ - if (ack == DMA_ACK) { - dma_chan_get(chan); - chan->client_count++; - } else if (ack == DMA_NAK) - return; - } - } - } +/** + * dma_chan_put - drop a reference to a dma channel's parent driver module + * @chan - channel to release + * + * Must be called under dma_list_mutex + */ +static void dma_chan_put(struct dma_chan *chan) +{ + if (!chan->client_count) + return; /* this channel failed alloc_chan_resources */ + chan->client_count--; + module_put(dma_chan_to_owner(chan)); + if (chan->client_count == 0) + chan->device->device_free_chan_resources(chan); } enum dma_status dma_sync_wait(struct dma_chan *chan, dma_cookie_t cookie) @@ -218,138 +269,342 @@ enum dma_status dma_sync_wait(struct dma_chan *chan, dma_cookie_t cookie) EXPORT_SYMBOL(dma_sync_wait); /** - * dma_chan_cleanup - release a DMA channel's resources - * @kref: kernel reference structure that contains the DMA channel device + * dma_cap_mask_all - enable iteration over all operation types + */ +static dma_cap_mask_t dma_cap_mask_all; + +/** + * dma_chan_tbl_ent - tracks channel allocations per core/operation + * @chan - associated channel for this entry + */ +struct dma_chan_tbl_ent { + struct dma_chan *chan; +}; + +/** + * channel_table - percpu lookup table for memory-to-memory offload providers */ -void dma_chan_cleanup(struct kref *kref) +static struct dma_chan_tbl_ent *channel_table[DMA_TX_TYPE_END]; + +static int __init dma_channel_table_init(void) { - struct dma_chan *chan = container_of(kref, struct dma_chan, refcount); - chan->device->device_free_chan_resources(chan); - kref_put(&chan->device->refcount, dma_async_device_cleanup); + enum dma_transaction_type cap; + int err = 0; + + bitmap_fill(dma_cap_mask_all.bits, DMA_TX_TYPE_END); + + /* 'interrupt', 'private', and 'slave' are channel capabilities, + * but are not associated with an operation so they do not need + * an entry in the channel_table + */ + clear_bit(DMA_INTERRUPT, dma_cap_mask_all.bits); + clear_bit(DMA_PRIVATE, dma_cap_mask_all.bits); + clear_bit(DMA_SLAVE, dma_cap_mask_all.bits); + + for_each_dma_cap_mask(cap, dma_cap_mask_all) { + channel_table[cap] = alloc_percpu(struct dma_chan_tbl_ent); + if (!channel_table[cap]) { + err = -ENOMEM; + break; + } + } + + if (err) { + pr_err("dmaengine: initialization failure\n"); + for_each_dma_cap_mask(cap, dma_cap_mask_all) + if (channel_table[cap]) + free_percpu(channel_table[cap]); + } + + return err; } -EXPORT_SYMBOL(dma_chan_cleanup); +arch_initcall(dma_channel_table_init); -static void dma_chan_free_rcu(struct rcu_head *rcu) +/** + * dma_find_channel - find a channel to carry out the operation + * @tx_type: transaction type + */ +struct dma_chan *dma_find_channel(enum dma_transaction_type tx_type) { - struct dma_chan *chan = container_of(rcu, struct dma_chan, rcu); - int bias = 0x7FFFFFFF; - int i; - for_each_possible_cpu(i) - bias -= local_read(&per_cpu_ptr(chan->local, i)->refcount); - atomic_sub(bias, &chan->refcount.refcount); - kref_put(&chan->refcount, dma_chan_cleanup); + struct dma_chan *chan; + int cpu; + + WARN_ONCE(dmaengine_ref_count == 0, + "client called %s without a reference", __func__); + + cpu = get_cpu(); + chan = per_cpu_ptr(channel_table[tx_type], cpu)->chan; + put_cpu(); + + return chan; } +EXPORT_SYMBOL(dma_find_channel); -static void dma_chan_release(struct dma_chan *chan) +/** + * dma_issue_pending_all - flush all pending operations across all channels + */ +void dma_issue_pending_all(void) { - atomic_add(0x7FFFFFFF, &chan->refcount.refcount); - chan->slow_ref = 1; - call_rcu(&chan->rcu, dma_chan_free_rcu); + struct dma_device *device; + struct dma_chan *chan; + + WARN_ONCE(dmaengine_ref_count == 0, + "client called %s without a reference", __func__); + + rcu_read_lock(); + list_for_each_entry_rcu(device, &dma_device_list, global_node) { + if (dma_has_cap(DMA_PRIVATE, device->cap_mask)) + continue; + list_for_each_entry(chan, &device->channels, device_node) + if (chan->client_count) + device->device_issue_pending(chan); + } + rcu_read_unlock(); } +EXPORT_SYMBOL(dma_issue_pending_all); /** - * dma_chans_notify_available - broadcast available channels to the clients + * nth_chan - returns the nth channel of the given capability + * @cap: capability to match + * @n: nth channel desired + * + * Defaults to returning the channel with the desired capability and the + * lowest reference count when 'n' cannot be satisfied. Must be called + * under dma_list_mutex. */ -static void dma_clients_notify_available(void) +static struct dma_chan *nth_chan(enum dma_transaction_type cap, int n) { - struct dma_client *client; + struct dma_device *device; + struct dma_chan *chan; + struct dma_chan *ret = NULL; + struct dma_chan *min = NULL; - mutex_lock(&dma_list_mutex); + list_for_each_entry(device, &dma_device_list, global_node) { + if (!dma_has_cap(cap, device->cap_mask) || + dma_has_cap(DMA_PRIVATE, device->cap_mask)) + continue; + list_for_each_entry(chan, &device->channels, device_node) { + if (!chan->client_count) + continue; + if (!min) + min = chan; + else if (chan->table_count < min->table_count) + min = chan; + + if (n-- == 0) { + ret = chan; + break; /* done */ + } + } + if (ret) + break; /* done */ + } - list_for_each_entry(client, &dma_client_list, global_node) - dma_client_chan_alloc(client); + if (!ret) + ret = min; - mutex_unlock(&dma_list_mutex); + if (ret) + ret->table_count++; + + return ret; } /** - * dma_chans_notify_available - tell the clients that a channel is going away - * @chan: channel on its way out + * dma_channel_rebalance - redistribute the available channels + * + * Optimize for cpu isolation (each cpu gets a dedicated channel for an + * operation type) in the SMP case, and operation isolation (avoid + * multi-tasking channels) in the non-SMP case. Must be called under + * dma_list_mutex. */ -static void dma_clients_notify_removed(struct dma_chan *chan) +static void dma_channel_rebalance(void) { - struct dma_client *client; - enum dma_state_client ack; + struct dma_chan *chan; + struct dma_device *device; + int cpu; + int cap; + int n; - mutex_lock(&dma_list_mutex); + /* undo the last distribution */ + for_each_dma_cap_mask(cap, dma_cap_mask_all) + for_each_possible_cpu(cpu) + per_cpu_ptr(channel_table[cap], cpu)->chan = NULL; + + list_for_each_entry(device, &dma_device_list, global_node) { + if (dma_has_cap(DMA_PRIVATE, device->cap_mask)) + continue; + list_for_each_entry(chan, &device->channels, device_node) + chan->table_count = 0; + } - list_for_each_entry(client, &dma_client_list, global_node) { - ack = client->event_callback(client, chan, - DMA_RESOURCE_REMOVED); + /* don't populate the channel_table if no clients are available */ + if (!dmaengine_ref_count) + return; - /* client was holding resources for this channel so - * free it - */ - if (ack == DMA_ACK) { - dma_chan_put(chan); - chan->client_count--; + /* redistribute available channels */ + n = 0; + for_each_dma_cap_mask(cap, dma_cap_mask_all) + for_each_online_cpu(cpu) { + if (num_possible_cpus() > 1) + chan = nth_chan(cap, n++); + else + chan = nth_chan(cap, -1); + + per_cpu_ptr(channel_table[cap], cpu)->chan = chan; + } +} + +static struct dma_chan *private_candidate(dma_cap_mask_t *mask, struct dma_device *dev, + dma_filter_fn fn, void *fn_param) +{ + struct dma_chan *chan; + + if (!__dma_device_satisfies_mask(dev, mask)) { + pr_debug("%s: wrong capabilities\n", __func__); + return NULL; + } + /* devices with multiple channels need special handling as we need to + * ensure that all channels are either private or public. + */ + if (dev->chancnt > 1 && !dma_has_cap(DMA_PRIVATE, dev->cap_mask)) + list_for_each_entry(chan, &dev->channels, device_node) { + /* some channels are already publicly allocated */ + if (chan->client_count) + return NULL; } + + list_for_each_entry(chan, &dev->channels, device_node) { + if (chan->client_count) { + pr_debug("%s: %s busy\n", + __func__, dma_chan_name(chan)); + continue; + } + if (fn && !fn(chan, fn_param)) { + pr_debug("%s: %s filter said false\n", + __func__, dma_chan_name(chan)); + continue; + } + return chan; } - mutex_unlock(&dma_list_mutex); + return NULL; } /** - * dma_async_client_register - register a &dma_client - * @client: ptr to a client structure with valid 'event_callback' and 'cap_mask' + * dma_request_channel - try to allocate an exclusive channel + * @mask: capabilities that the channel must satisfy + * @fn: optional callback to disposition available channels + * @fn_param: opaque parameter to pass to dma_filter_fn */ -void dma_async_client_register(struct dma_client *client) +struct dma_chan *__dma_request_channel(dma_cap_mask_t *mask, dma_filter_fn fn, void *fn_param) { - /* validate client data */ - BUG_ON(dma_has_cap(DMA_SLAVE, client->cap_mask) && - !client->slave); + struct dma_device *device, *_d; + struct dma_chan *chan = NULL; + int err; + /* Find a channel */ + mutex_lock(&dma_list_mutex); + list_for_each_entry_safe(device, _d, &dma_device_list, global_node) { + chan = private_candidate(mask, device, fn, fn_param); + if (chan) { + /* Found a suitable channel, try to grab, prep, and + * return it. We first set DMA_PRIVATE to disable + * balance_ref_count as this channel will not be + * published in the general-purpose allocator + */ + dma_cap_set(DMA_PRIVATE, device->cap_mask); + err = dma_chan_get(chan); + + if (err == -ENODEV) { + pr_debug("%s: %s module removed\n", __func__, + dma_chan_name(chan)); + list_del_rcu(&device->global_node); + } else if (err) + pr_err("dmaengine: failed to get %s: (%d)\n", + dma_chan_name(chan), err); + else + break; + chan = NULL; + } + } + mutex_unlock(&dma_list_mutex); + + pr_debug("%s: %s (%s)\n", __func__, chan ? "success" : "fail", + chan ? dma_chan_name(chan) : NULL); + + return chan; +} +EXPORT_SYMBOL_GPL(__dma_request_channel); + +void dma_release_channel(struct dma_chan *chan) +{ mutex_lock(&dma_list_mutex); - list_add_tail(&client->global_node, &dma_client_list); + WARN_ONCE(chan->client_count != 1, + "chan reference count %d != 1\n", chan->client_count); + dma_chan_put(chan); mutex_unlock(&dma_list_mutex); } -EXPORT_SYMBOL(dma_async_client_register); +EXPORT_SYMBOL_GPL(dma_release_channel); /** - * dma_async_client_unregister - unregister a client and free the &dma_client - * @client: &dma_client to free - * - * Force frees any allocated DMA channels, frees the &dma_client memory + * dmaengine_get - register interest in dma_channels */ -void dma_async_client_unregister(struct dma_client *client) +void dmaengine_get(void) { - struct dma_device *device; + struct dma_device *device, *_d; struct dma_chan *chan; - enum dma_state_client ack; - - if (!client) - return; + int err; mutex_lock(&dma_list_mutex); - /* free all channels the client is holding */ - list_for_each_entry(device, &dma_device_list, global_node) - list_for_each_entry(chan, &device->channels, device_node) { - ack = client->event_callback(client, chan, - DMA_RESOURCE_REMOVED); + dmaengine_ref_count++; - if (ack == DMA_ACK) { - dma_chan_put(chan); - chan->client_count--; - } + /* try to grab channels */ + list_for_each_entry_safe(device, _d, &dma_device_list, global_node) { + if (dma_has_cap(DMA_PRIVATE, device->cap_mask)) + continue; + list_for_each_entry(chan, &device->channels, device_node) { + err = dma_chan_get(chan); + if (err == -ENODEV) { + /* module removed before we could use it */ + list_del_rcu(&device->global_node); + break; + } else if (err) + pr_err("dmaengine: failed to get %s: (%d)\n", + dma_chan_name(chan), err); } + } - list_del(&client->global_node); + /* if this is the first reference and there were channels + * waiting we need to rebalance to get those channels + * incorporated into the channel table + */ + if (dmaengine_ref_count == 1) + dma_channel_rebalance(); mutex_unlock(&dma_list_mutex); } -EXPORT_SYMBOL(dma_async_client_unregister); +EXPORT_SYMBOL(dmaengine_get); /** - * dma_async_client_chan_request - send all available channels to the - * client that satisfy the capability mask - * @client - requester + * dmaengine_put - let dma drivers be removed when ref_count == 0 */ -void dma_async_client_chan_request(struct dma_client *client) +void dmaengine_put(void) { + struct dma_device *device; + struct dma_chan *chan; + mutex_lock(&dma_list_mutex); - dma_client_chan_alloc(client); + dmaengine_ref_count--; + BUG_ON(dmaengine_ref_count < 0); + /* drop channel references */ + list_for_each_entry(device, &dma_device_list, global_node) { + if (dma_has_cap(DMA_PRIVATE, device->cap_mask)) + continue; + list_for_each_entry(chan, &device->channels, device_node) + dma_chan_put(chan); + } mutex_unlock(&dma_list_mutex); } -EXPORT_SYMBOL(dma_async_client_chan_request); +EXPORT_SYMBOL(dmaengine_put); /** * dma_async_device_register - registers DMA devices found @@ -357,9 +612,9 @@ EXPORT_SYMBOL(dma_async_client_chan_request); */ int dma_async_device_register(struct dma_device *device) { - static int id; int chancnt = 0, rc; struct dma_chan* chan; + atomic_t *idr_ref; if (!device) return -ENODEV; @@ -386,57 +641,83 @@ int dma_async_device_register(struct dma_device *device) BUG_ON(!device->device_issue_pending); BUG_ON(!device->dev); - init_completion(&device->done); - kref_init(&device->refcount); - + idr_ref = kmalloc(sizeof(*idr_ref), GFP_KERNEL); + if (!idr_ref) + return -ENOMEM; + atomic_set(idr_ref, 0); + idr_retry: + if (!idr_pre_get(&dma_idr, GFP_KERNEL)) + return -ENOMEM; mutex_lock(&dma_list_mutex); - device->dev_id = id++; + rc = idr_get_new(&dma_idr, NULL, &device->dev_id); mutex_unlock(&dma_list_mutex); + if (rc == -EAGAIN) + goto idr_retry; + else if (rc != 0) + return rc; /* represent channels in sysfs. Probably want devs too */ list_for_each_entry(chan, &device->channels, device_node) { chan->local = alloc_percpu(typeof(*chan->local)); if (chan->local == NULL) continue; + chan->dev = kzalloc(sizeof(*chan->dev), GFP_KERNEL); + if (chan->dev == NULL) { + free_percpu(chan->local); + continue; + } chan->chan_id = chancnt++; - chan->dev.class = &dma_devclass; - chan->dev.parent = device->dev; - dev_set_name(&chan->dev, "dma%dchan%d", + chan->dev->device.class = &dma_devclass; + chan->dev->device.parent = device->dev; + chan->dev->chan = chan; + chan->dev->idr_ref = idr_ref; + chan->dev->dev_id = device->dev_id; + atomic_inc(idr_ref); + dev_set_name(&chan->dev->device, "dma%dchan%d", device->dev_id, chan->chan_id); - rc = device_register(&chan->dev); + rc = device_register(&chan->dev->device); if (rc) { - chancnt--; free_percpu(chan->local); chan->local = NULL; goto err_out; } - - /* One for the channel, one of the class device */ - kref_get(&device->refcount); - kref_get(&device->refcount); - kref_init(&chan->refcount); chan->client_count = 0; - chan->slow_ref = 0; - INIT_RCU_HEAD(&chan->rcu); } + device->chancnt = chancnt; mutex_lock(&dma_list_mutex); - list_add_tail(&device->global_node, &dma_device_list); + /* take references on public channels */ + if (dmaengine_ref_count && !dma_has_cap(DMA_PRIVATE, device->cap_mask)) + list_for_each_entry(chan, &device->channels, device_node) { + /* if clients are already waiting for channels we need + * to take references on their behalf + */ + if (dma_chan_get(chan) == -ENODEV) { + /* note we can only get here for the first + * channel as the remaining channels are + * guaranteed to get a reference + */ + rc = -ENODEV; + mutex_unlock(&dma_list_mutex); + goto err_out; + } + } + list_add_tail_rcu(&device->global_node, &dma_device_list); + dma_channel_rebalance(); mutex_unlock(&dma_list_mutex); - dma_clients_notify_available(); - return 0; err_out: list_for_each_entry(chan, &device->channels, device_node) { if (chan->local == NULL) continue; - kref_put(&device->refcount, dma_async_device_cleanup); - device_unregister(&chan->dev); - chancnt--; + mutex_lock(&dma_list_mutex); + chan->dev->chan = NULL; + mutex_unlock(&dma_list_mutex); + device_unregister(&chan->dev->device); free_percpu(chan->local); } return rc; @@ -444,37 +725,30 @@ err_out: EXPORT_SYMBOL(dma_async_device_register); /** - * dma_async_device_cleanup - function called when all references are released - * @kref: kernel reference object - */ -static void dma_async_device_cleanup(struct kref *kref) -{ - struct dma_device *device; - - device = container_of(kref, struct dma_device, refcount); - complete(&device->done); -} - -/** - * dma_async_device_unregister - unregisters DMA devices + * dma_async_device_unregister - unregister a DMA device * @device: &dma_device + * + * This routine is called by dma driver exit routines, dmaengine holds module + * references to prevent it being called while channels are in use. */ void dma_async_device_unregister(struct dma_device *device) { struct dma_chan *chan; mutex_lock(&dma_list_mutex); - list_del(&device->global_node); + list_del_rcu(&device->global_node); + dma_channel_rebalance(); mutex_unlock(&dma_list_mutex); list_for_each_entry(chan, &device->channels, device_node) { - dma_clients_notify_removed(chan); - device_unregister(&chan->dev); - dma_chan_release(chan); + WARN_ONCE(chan->client_count, + "%s called while %d clients hold a reference\n", + __func__, chan->client_count); + mutex_lock(&dma_list_mutex); + chan->dev->chan = NULL; + mutex_unlock(&dma_list_mutex); + device_unregister(&chan->dev->device); } - - kref_put(&device->refcount, dma_async_device_cleanup); - wait_for_completion(&device->done); } EXPORT_SYMBOL(dma_async_device_unregister); @@ -626,10 +900,96 @@ void dma_async_tx_descriptor_init(struct dma_async_tx_descriptor *tx, } EXPORT_SYMBOL(dma_async_tx_descriptor_init); +/* dma_wait_for_async_tx - spin wait for a transaction to complete + * @tx: in-flight transaction to wait on + * + * This routine assumes that tx was obtained from a call to async_memcpy, + * async_xor, async_memset, etc which ensures that tx is "in-flight" (prepped + * and submitted). Walking the parent chain is only meant to cover for DMA + * drivers that do not implement the DMA_INTERRUPT capability and may race with + * the driver's descriptor cleanup routine. + */ +enum dma_status +dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx) +{ + enum dma_status status; + struct dma_async_tx_descriptor *iter; + struct dma_async_tx_descriptor *parent; + + if (!tx) + return DMA_SUCCESS; + + WARN_ONCE(tx->parent, "%s: speculatively walking dependency chain for" + " %s\n", __func__, dma_chan_name(tx->chan)); + + /* poll through the dependency chain, return when tx is complete */ + do { + iter = tx; + + /* find the root of the unsubmitted dependency chain */ + do { + parent = iter->parent; + if (!parent) + break; + else + iter = parent; + } while (parent); + + /* there is a small window for ->parent == NULL and + * ->cookie == -EBUSY + */ + while (iter->cookie == -EBUSY) + cpu_relax(); + + status = dma_sync_wait(iter->chan, iter->cookie); + } while (status == DMA_IN_PROGRESS || (iter != tx)); + + return status; +} +EXPORT_SYMBOL_GPL(dma_wait_for_async_tx); + +/* dma_run_dependencies - helper routine for dma drivers to process + * (start) dependent operations on their target channel + * @tx: transaction with dependencies + */ +void dma_run_dependencies(struct dma_async_tx_descriptor *tx) +{ + struct dma_async_tx_descriptor *dep = tx->next; + struct dma_async_tx_descriptor *dep_next; + struct dma_chan *chan; + + if (!dep) + return; + + chan = dep->chan; + + /* keep submitting up until a channel switch is detected + * in that case we will be called again as a result of + * processing the interrupt from async_tx_channel_switch + */ + for (; dep; dep = dep_next) { + spin_lock_bh(&dep->lock); + dep->parent = NULL; + dep_next = dep->next; + if (dep_next && dep_next->chan == chan) + dep->next = NULL; /* ->next will be submitted */ + else + dep_next = NULL; /* submit current dep and terminate */ + spin_unlock_bh(&dep->lock); + + dep->tx_submit(dep); + } + + chan->device->device_issue_pending(chan); +} +EXPORT_SYMBOL_GPL(dma_run_dependencies); + static int __init dma_bus_init(void) { + idr_init(&dma_idr); mutex_init(&dma_list_mutex); return class_register(&dma_devclass); } -subsys_initcall(dma_bus_init); +arch_initcall(dma_bus_init); + diff --git a/drivers/dma/dmatest.c b/drivers/dma/dmatest.c index ed9636b..3603f1e 100644 --- a/drivers/dma/dmatest.c +++ b/drivers/dma/dmatest.c @@ -35,7 +35,7 @@ MODULE_PARM_DESC(threads_per_chan, static unsigned int max_channels; module_param(max_channels, uint, S_IRUGO); -MODULE_PARM_DESC(nr_channels, +MODULE_PARM_DESC(max_channels, "Maximum number of channels to use (default: all)"); /* @@ -71,7 +71,7 @@ struct dmatest_chan { /* * These are protected by dma_list_mutex since they're only used by - * the DMA client event callback + * the DMA filter function callback */ static LIST_HEAD(dmatest_channels); static unsigned int nr_channels; @@ -80,7 +80,7 @@ static bool dmatest_match_channel(struct dma_chan *chan) { if (test_channel[0] == '\0') return true; - return strcmp(dev_name(&chan->dev), test_channel) == 0; + return strcmp(dma_chan_name(chan), test_channel) == 0; } static bool dmatest_match_device(struct dma_device *device) @@ -215,7 +215,6 @@ static int dmatest_func(void *data) smp_rmb(); chan = thread->chan; - dma_chan_get(chan); while (!kthread_should_stop()) { total_tests++; @@ -293,7 +292,6 @@ static int dmatest_func(void *data) } ret = 0; - dma_chan_put(chan); kfree(thread->dstbuf); err_dstbuf: kfree(thread->srcbuf); @@ -319,21 +317,16 @@ static void dmatest_cleanup_channel(struct dmatest_chan *dtc) kfree(dtc); } -static enum dma_state_client dmatest_add_channel(struct dma_chan *chan) +static int dmatest_add_channel(struct dma_chan *chan) { struct dmatest_chan *dtc; struct dmatest_thread *thread; unsigned int i; - /* Have we already been told about this channel? */ - list_for_each_entry(dtc, &dmatest_channels, node) - if (dtc->chan == chan) - return DMA_DUP; - dtc = kmalloc(sizeof(struct dmatest_chan), GFP_KERNEL); if (!dtc) { - pr_warning("dmatest: No memory for %s\n", dev_name(&chan->dev)); - return DMA_NAK; + pr_warning("dmatest: No memory for %s\n", dma_chan_name(chan)); + return -ENOMEM; } dtc->chan = chan; @@ -343,16 +336,16 @@ static enum dma_state_client dmatest_add_channel(struct dma_chan *chan) thread = kzalloc(sizeof(struct dmatest_thread), GFP_KERNEL); if (!thread) { pr_warning("dmatest: No memory for %s-test%u\n", - dev_name(&chan->dev), i); + dma_chan_name(chan), i); break; } thread->chan = dtc->chan; smp_wmb(); thread->task = kthread_run(dmatest_func, thread, "%s-test%u", - dev_name(&chan->dev), i); + dma_chan_name(chan), i); if (IS_ERR(thread->task)) { pr_warning("dmatest: Failed to run thread %s-test%u\n", - dev_name(&chan->dev), i); + dma_chan_name(chan), i); kfree(thread); break; } @@ -362,86 +355,62 @@ static enum dma_state_client dmatest_add_channel(struct dma_chan *chan) list_add_tail(&thread->node, &dtc->threads); } - pr_info("dmatest: Started %u threads using %s\n", i, dev_name(&chan->dev)); + pr_info("dmatest: Started %u threads using %s\n", i, dma_chan_name(chan)); list_add_tail(&dtc->node, &dmatest_channels); nr_channels++; - return DMA_ACK; -} - -static enum dma_state_client dmatest_remove_channel(struct dma_chan *chan) -{ - struct dmatest_chan *dtc, *_dtc; - - list_for_each_entry_safe(dtc, _dtc, &dmatest_channels, node) { - if (dtc->chan == chan) { - list_del(&dtc->node); - dmatest_cleanup_channel(dtc); - pr_debug("dmatest: lost channel %s\n", - dev_name(&chan->dev)); - return DMA_ACK; - } - } - - return DMA_DUP; + return 0; } -/* - * Start testing threads as new channels are assigned to us, and kill - * them when the channels go away. - * - * When we unregister the client, all channels are removed so this - * will also take care of cleaning things up when the module is - * unloaded. - */ -static enum dma_state_client -dmatest_event(struct dma_client *client, struct dma_chan *chan, - enum dma_state state) +static bool filter(struct dma_chan *chan, void *param) { - enum dma_state_client ack = DMA_NAK; - - switch (state) { - case DMA_RESOURCE_AVAILABLE: - if (!dmatest_match_channel(chan) - || !dmatest_match_device(chan->device)) - ack = DMA_DUP; - else if (max_channels && nr_channels >= max_channels) - ack = DMA_NAK; - else - ack = dmatest_add_channel(chan); - break; - - case DMA_RESOURCE_REMOVED: - ack = dmatest_remove_channel(chan); - break; - - default: - pr_info("dmatest: Unhandled event %u (%s)\n", - state, dev_name(&chan->dev)); - break; - } - - return ack; + if (!dmatest_match_channel(chan) || !dmatest_match_device(chan->device)) + return false; + else + return true; } -static struct dma_client dmatest_client = { - .event_callback = dmatest_event, -}; - static int __init dmatest_init(void) { - dma_cap_set(DMA_MEMCPY, dmatest_client.cap_mask); - dma_async_client_register(&dmatest_client); - dma_async_client_chan_request(&dmatest_client); + dma_cap_mask_t mask; + struct dma_chan *chan; + int err = 0; + + dma_cap_zero(mask); + dma_cap_set(DMA_MEMCPY, mask); + for (;;) { + chan = dma_request_channel(mask, filter, NULL); + if (chan) { + err = dmatest_add_channel(chan); + if (err == 0) + continue; + else { + dma_release_channel(chan); + break; /* add_channel failed, punt */ + } + } else + break; /* no more channels available */ + if (max_channels && nr_channels >= max_channels) + break; /* we have all we need */ + } - return 0; + return err; } -module_init(dmatest_init); +/* when compiled-in wait for drivers to load first */ +late_initcall(dmatest_init); static void __exit dmatest_exit(void) { - dma_async_client_unregister(&dmatest_client); + struct dmatest_chan *dtc, *_dtc; + + list_for_each_entry_safe(dtc, _dtc, &dmatest_channels, node) { + list_del(&dtc->node); + dmatest_cleanup_channel(dtc); + pr_debug("dmatest: dropped channel %s\n", + dma_chan_name(dtc->chan)); + dma_release_channel(dtc->chan); + } } module_exit(dmatest_exit); diff --git a/drivers/dma/dw_dmac.c b/drivers/dma/dw_dmac.c index 0778d99..6b702cc 100644 --- a/drivers/dma/dw_dmac.c +++ b/drivers/dma/dw_dmac.c @@ -70,6 +70,15 @@ * the controller, though. */ +static struct device *chan2dev(struct dma_chan *chan) +{ + return &chan->dev->device; +} +static struct device *chan2parent(struct dma_chan *chan) +{ + return chan->dev->device.parent; +} + static struct dw_desc *dwc_first_active(struct dw_dma_chan *dwc) { return list_entry(dwc->active_list.next, struct dw_desc, desc_node); @@ -93,12 +102,12 @@ static struct dw_desc *dwc_desc_get(struct dw_dma_chan *dwc) ret = desc; break; } - dev_dbg(&dwc->chan.dev, "desc %p not ACKed\n", desc); + dev_dbg(chan2dev(&dwc->chan), "desc %p not ACKed\n", desc); i++; } spin_unlock_bh(&dwc->lock); - dev_vdbg(&dwc->chan.dev, "scanned %u descriptors on freelist\n", i); + dev_vdbg(chan2dev(&dwc->chan), "scanned %u descriptors on freelist\n", i); return ret; } @@ -108,10 +117,10 @@ static void dwc_sync_desc_for_cpu(struct dw_dma_chan *dwc, struct dw_desc *desc) struct dw_desc *child; list_for_each_entry(child, &desc->txd.tx_list, desc_node) - dma_sync_single_for_cpu(dwc->chan.dev.parent, + dma_sync_single_for_cpu(chan2parent(&dwc->chan), child->txd.phys, sizeof(child->lli), DMA_TO_DEVICE); - dma_sync_single_for_cpu(dwc->chan.dev.parent, + dma_sync_single_for_cpu(chan2parent(&dwc->chan), desc->txd.phys, sizeof(desc->lli), DMA_TO_DEVICE); } @@ -129,11 +138,11 @@ static void dwc_desc_put(struct dw_dma_chan *dwc, struct dw_desc *desc) spin_lock_bh(&dwc->lock); list_for_each_entry(child, &desc->txd.tx_list, desc_node) - dev_vdbg(&dwc->chan.dev, + dev_vdbg(chan2dev(&dwc->chan), "moving child desc %p to freelist\n", child); list_splice_init(&desc->txd.tx_list, &dwc->free_list); - dev_vdbg(&dwc->chan.dev, "moving desc %p to freelist\n", desc); + dev_vdbg(chan2dev(&dwc->chan), "moving desc %p to freelist\n", desc); list_add(&desc->desc_node, &dwc->free_list); spin_unlock_bh(&dwc->lock); } @@ -163,9 +172,9 @@ static void dwc_dostart(struct dw_dma_chan *dwc, struct dw_desc *first) /* ASSERT: channel is idle */ if (dma_readl(dw, CH_EN) & dwc->mask) { - dev_err(&dwc->chan.dev, + dev_err(chan2dev(&dwc->chan), "BUG: Attempted to start non-idle channel\n"); - dev_err(&dwc->chan.dev, + dev_err(chan2dev(&dwc->chan), " SAR: 0x%x DAR: 0x%x LLP: 0x%x CTL: 0x%x:%08x\n", channel_readl(dwc, SAR), channel_readl(dwc, DAR), @@ -193,7 +202,7 @@ dwc_descriptor_complete(struct dw_dma_chan *dwc, struct dw_desc *desc) void *param; struct dma_async_tx_descriptor *txd = &desc->txd; - dev_vdbg(&dwc->chan.dev, "descriptor %u complete\n", txd->cookie); + dev_vdbg(chan2dev(&dwc->chan), "descriptor %u complete\n", txd->cookie); dwc->completed = txd->cookie; callback = txd->callback; @@ -208,11 +217,11 @@ dwc_descriptor_complete(struct dw_dma_chan *dwc, struct dw_desc *desc) * mapped before they were submitted... */ if (!(txd->flags & DMA_COMPL_SKIP_DEST_UNMAP)) - dma_unmap_page(dwc->chan.dev.parent, desc->lli.dar, desc->len, - DMA_FROM_DEVICE); + dma_unmap_page(chan2parent(&dwc->chan), desc->lli.dar, + desc->len, DMA_FROM_DEVICE); if (!(txd->flags & DMA_COMPL_SKIP_SRC_UNMAP)) - dma_unmap_page(dwc->chan.dev.parent, desc->lli.sar, desc->len, - DMA_TO_DEVICE); + dma_unmap_page(chan2parent(&dwc->chan), desc->lli.sar, + desc->len, DMA_TO_DEVICE); /* * The API requires that no submissions are done from a @@ -228,7 +237,7 @@ static void dwc_complete_all(struct dw_dma *dw, struct dw_dma_chan *dwc) LIST_HEAD(list); if (dma_readl(dw, CH_EN) & dwc->mask) { - dev_err(&dwc->chan.dev, + dev_err(chan2dev(&dwc->chan), "BUG: XFER bit set, but channel not idle!\n"); /* Try to continue after resetting the channel... */ @@ -273,7 +282,7 @@ static void dwc_scan_descriptors(struct dw_dma *dw, struct dw_dma_chan *dwc) return; } - dev_vdbg(&dwc->chan.dev, "scan_descriptors: llp=0x%x\n", llp); + dev_vdbg(chan2dev(&dwc->chan), "scan_descriptors: llp=0x%x\n", llp); list_for_each_entry_safe(desc, _desc, &dwc->active_list, desc_node) { if (desc->lli.llp == llp) @@ -292,7 +301,7 @@ static void dwc_scan_descriptors(struct dw_dma *dw, struct dw_dma_chan *dwc) dwc_descriptor_complete(dwc, desc); } - dev_err(&dwc->chan.dev, + dev_err(chan2dev(&dwc->chan), "BUG: All descriptors done, but channel not idle!\n"); /* Try to continue after resetting the channel... */ @@ -308,7 +317,7 @@ static void dwc_scan_descriptors(struct dw_dma *dw, struct dw_dma_chan *dwc) static void dwc_dump_lli(struct dw_dma_chan *dwc, struct dw_lli *lli) { - dev_printk(KERN_CRIT, &dwc->chan.dev, + dev_printk(KERN_CRIT, chan2dev(&dwc->chan), " desc: s0x%x d0x%x l0x%x c0x%x:%x\n", lli->sar, lli->dar, lli->llp, lli->ctlhi, lli->ctllo); @@ -342,9 +351,9 @@ static void dwc_handle_error(struct dw_dma *dw, struct dw_dma_chan *dwc) * controller flagged an error instead of scribbling over * random memory locations. */ - dev_printk(KERN_CRIT, &dwc->chan.dev, + dev_printk(KERN_CRIT, chan2dev(&dwc->chan), "Bad descriptor submitted for DMA!\n"); - dev_printk(KERN_CRIT, &dwc->chan.dev, + dev_printk(KERN_CRIT, chan2dev(&dwc->chan), " cookie: %d\n", bad_desc->txd.cookie); dwc_dump_lli(dwc, &bad_desc->lli); list_for_each_entry(child, &bad_desc->txd.tx_list, desc_node) @@ -442,12 +451,12 @@ static dma_cookie_t dwc_tx_submit(struct dma_async_tx_descriptor *tx) * for DMA. But this is hard to do in a race-free manner. */ if (list_empty(&dwc->active_list)) { - dev_vdbg(&tx->chan->dev, "tx_submit: started %u\n", + dev_vdbg(chan2dev(tx->chan), "tx_submit: started %u\n", desc->txd.cookie); dwc_dostart(dwc, desc); list_add_tail(&desc->desc_node, &dwc->active_list); } else { - dev_vdbg(&tx->chan->dev, "tx_submit: queued %u\n", + dev_vdbg(chan2dev(tx->chan), "tx_submit: queued %u\n", desc->txd.cookie); list_add_tail(&desc->desc_node, &dwc->queue); @@ -472,11 +481,11 @@ dwc_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, unsigned int dst_width; u32 ctllo; - dev_vdbg(&chan->dev, "prep_dma_memcpy d0x%x s0x%x l0x%zx f0x%lx\n", + dev_vdbg(chan2dev(chan), "prep_dma_memcpy d0x%x s0x%x l0x%zx f0x%lx\n", dest, src, len, flags); if (unlikely(!len)) { - dev_dbg(&chan->dev, "prep_dma_memcpy: length is zero!\n"); + dev_dbg(chan2dev(chan), "prep_dma_memcpy: length is zero!\n"); return NULL; } @@ -516,7 +525,7 @@ dwc_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, first = desc; } else { prev->lli.llp = desc->txd.phys; - dma_sync_single_for_device(chan->dev.parent, + dma_sync_single_for_device(chan2parent(chan), prev->txd.phys, sizeof(prev->lli), DMA_TO_DEVICE); list_add_tail(&desc->desc_node, @@ -531,7 +540,7 @@ dwc_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, prev->lli.ctllo |= DWC_CTLL_INT_EN; prev->lli.llp = 0; - dma_sync_single_for_device(chan->dev.parent, + dma_sync_single_for_device(chan2parent(chan), prev->txd.phys, sizeof(prev->lli), DMA_TO_DEVICE); @@ -562,15 +571,15 @@ dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, struct scatterlist *sg; size_t total_len = 0; - dev_vdbg(&chan->dev, "prep_dma_slave\n"); + dev_vdbg(chan2dev(chan), "prep_dma_slave\n"); if (unlikely(!dws || !sg_len)) return NULL; - reg_width = dws->slave.reg_width; + reg_width = dws->reg_width; prev = first = NULL; - sg_len = dma_map_sg(chan->dev.parent, sgl, sg_len, direction); + sg_len = dma_map_sg(chan2parent(chan), sgl, sg_len, direction); switch (direction) { case DMA_TO_DEVICE: @@ -579,7 +588,7 @@ dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, | DWC_CTLL_DST_FIX | DWC_CTLL_SRC_INC | DWC_CTLL_FC_M2P); - reg = dws->slave.tx_reg; + reg = dws->tx_reg; for_each_sg(sgl, sg, sg_len, i) { struct dw_desc *desc; u32 len; @@ -587,7 +596,7 @@ dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, desc = dwc_desc_get(dwc); if (!desc) { - dev_err(&chan->dev, + dev_err(chan2dev(chan), "not enough descriptors available\n"); goto err_desc_get; } @@ -607,7 +616,7 @@ dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, first = desc; } else { prev->lli.llp = desc->txd.phys; - dma_sync_single_for_device(chan->dev.parent, + dma_sync_single_for_device(chan2parent(chan), prev->txd.phys, sizeof(prev->lli), DMA_TO_DEVICE); @@ -625,7 +634,7 @@ dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, | DWC_CTLL_SRC_FIX | DWC_CTLL_FC_P2M); - reg = dws->slave.rx_reg; + reg = dws->rx_reg; for_each_sg(sgl, sg, sg_len, i) { struct dw_desc *desc; u32 len; @@ -633,7 +642,7 @@ dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, desc = dwc_desc_get(dwc); if (!desc) { - dev_err(&chan->dev, + dev_err(chan2dev(chan), "not enough descriptors available\n"); goto err_desc_get; } @@ -653,7 +662,7 @@ dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, first = desc; } else { prev->lli.llp = desc->txd.phys; - dma_sync_single_for_device(chan->dev.parent, + dma_sync_single_for_device(chan2parent(chan), prev->txd.phys, sizeof(prev->lli), DMA_TO_DEVICE); @@ -673,7 +682,7 @@ dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, prev->lli.ctllo |= DWC_CTLL_INT_EN; prev->lli.llp = 0; - dma_sync_single_for_device(chan->dev.parent, + dma_sync_single_for_device(chan2parent(chan), prev->txd.phys, sizeof(prev->lli), DMA_TO_DEVICE); @@ -758,29 +767,21 @@ static void dwc_issue_pending(struct dma_chan *chan) spin_unlock_bh(&dwc->lock); } -static int dwc_alloc_chan_resources(struct dma_chan *chan, - struct dma_client *client) +static int dwc_alloc_chan_resources(struct dma_chan *chan) { struct dw_dma_chan *dwc = to_dw_dma_chan(chan); struct dw_dma *dw = to_dw_dma(chan->device); struct dw_desc *desc; - struct dma_slave *slave; struct dw_dma_slave *dws; int i; u32 cfghi; u32 cfglo; - dev_vdbg(&chan->dev, "alloc_chan_resources\n"); - - /* Channels doing slave DMA can only handle one client. */ - if (dwc->dws || client->slave) { - if (chan->client_count) - return -EBUSY; - } + dev_vdbg(chan2dev(chan), "alloc_chan_resources\n"); /* ASSERT: channel is idle */ if (dma_readl(dw, CH_EN) & dwc->mask) { - dev_dbg(&chan->dev, "DMA channel not idle?\n"); + dev_dbg(chan2dev(chan), "DMA channel not idle?\n"); return -EIO; } @@ -789,23 +790,17 @@ static int dwc_alloc_chan_resources(struct dma_chan *chan, cfghi = DWC_CFGH_FIFO_MODE; cfglo = 0; - slave = client->slave; - if (slave) { + dws = dwc->dws; + if (dws) { /* * We need controller-specific data to set up slave * transfers. */ - BUG_ON(!slave->dma_dev || slave->dma_dev != dw->dma.dev); - - dws = container_of(slave, struct dw_dma_slave, slave); + BUG_ON(!dws->dma_dev || dws->dma_dev != dw->dma.dev); - dwc->dws = dws; cfghi = dws->cfg_hi; cfglo = dws->cfg_lo; - } else { - dwc->dws = NULL; } - channel_writel(dwc, CFG_LO, cfglo); channel_writel(dwc, CFG_HI, cfghi); @@ -822,7 +817,7 @@ static int dwc_alloc_chan_resources(struct dma_chan *chan, desc = kzalloc(sizeof(struct dw_desc), GFP_KERNEL); if (!desc) { - dev_info(&chan->dev, + dev_info(chan2dev(chan), "only allocated %d descriptors\n", i); spin_lock_bh(&dwc->lock); break; @@ -832,7 +827,7 @@ static int dwc_alloc_chan_resources(struct dma_chan *chan, desc->txd.tx_submit = dwc_tx_submit; desc->txd.flags = DMA_CTRL_ACK; INIT_LIST_HEAD(&desc->txd.tx_list); - desc->txd.phys = dma_map_single(chan->dev.parent, &desc->lli, + desc->txd.phys = dma_map_single(chan2parent(chan), &desc->lli, sizeof(desc->lli), DMA_TO_DEVICE); dwc_desc_put(dwc, desc); @@ -847,7 +842,7 @@ static int dwc_alloc_chan_resources(struct dma_chan *chan, spin_unlock_bh(&dwc->lock); - dev_dbg(&chan->dev, + dev_dbg(chan2dev(chan), "alloc_chan_resources allocated %d descriptors\n", i); return i; @@ -860,7 +855,7 @@ static void dwc_free_chan_resources(struct dma_chan *chan) struct dw_desc *desc, *_desc; LIST_HEAD(list); - dev_dbg(&chan->dev, "free_chan_resources (descs allocated=%u)\n", + dev_dbg(chan2dev(chan), "free_chan_resources (descs allocated=%u)\n", dwc->descs_allocated); /* ASSERT: channel is idle */ @@ -881,13 +876,13 @@ static void dwc_free_chan_resources(struct dma_chan *chan) spin_unlock_bh(&dwc->lock); list_for_each_entry_safe(desc, _desc, &list, desc_node) { - dev_vdbg(&chan->dev, " freeing descriptor %p\n", desc); - dma_unmap_single(chan->dev.parent, desc->txd.phys, + dev_vdbg(chan2dev(chan), " freeing descriptor %p\n", desc); + dma_unmap_single(chan2parent(chan), desc->txd.phys, sizeof(desc->lli), DMA_TO_DEVICE); kfree(desc); } - dev_vdbg(&chan->dev, "free_chan_resources done\n"); + dev_vdbg(chan2dev(chan), "free_chan_resources done\n"); } /*----------------------------------------------------------------------*/ diff --git a/drivers/dma/fsldma.c b/drivers/dma/fsldma.c index 0b95dcc..ca70a21 100644 --- a/drivers/dma/fsldma.c +++ b/drivers/dma/fsldma.c @@ -366,8 +366,7 @@ static struct fsl_desc_sw *fsl_dma_alloc_descriptor( * * Return - The number of descriptors allocated. */ -static int fsl_dma_alloc_chan_resources(struct dma_chan *chan, - struct dma_client *client) +static int fsl_dma_alloc_chan_resources(struct dma_chan *chan) { struct fsl_dma_chan *fsl_chan = to_fsl_chan(chan); @@ -823,7 +822,7 @@ static int __devinit fsl_dma_chan_probe(struct fsl_dma_device *fdev, */ WARN_ON(fdev->feature != new_fsl_chan->feature); - new_fsl_chan->dev = &new_fsl_chan->common.dev; + new_fsl_chan->dev = &new_fsl_chan->common.dev->device; new_fsl_chan->reg_base = ioremap(new_fsl_chan->reg.start, new_fsl_chan->reg.end - new_fsl_chan->reg.start + 1); diff --git a/drivers/dma/ioat.c b/drivers/dma/ioat.c index 9b16a3a..4105d65 100644 --- a/drivers/dma/ioat.c +++ b/drivers/dma/ioat.c @@ -75,60 +75,10 @@ static int ioat_dca_enabled = 1; module_param(ioat_dca_enabled, int, 0644); MODULE_PARM_DESC(ioat_dca_enabled, "control support of dca service (default: 1)"); -static int ioat_setup_functionality(struct pci_dev *pdev, void __iomem *iobase) -{ - struct ioat_device *device = pci_get_drvdata(pdev); - u8 version; - int err = 0; - - version = readb(iobase + IOAT_VER_OFFSET); - switch (version) { - case IOAT_VER_1_2: - device->dma = ioat_dma_probe(pdev, iobase); - if (device->dma && ioat_dca_enabled) - device->dca = ioat_dca_init(pdev, iobase); - break; - case IOAT_VER_2_0: - device->dma = ioat_dma_probe(pdev, iobase); - if (device->dma && ioat_dca_enabled) - device->dca = ioat2_dca_init(pdev, iobase); - break; - case IOAT_VER_3_0: - device->dma = ioat_dma_probe(pdev, iobase); - if (device->dma && ioat_dca_enabled) - device->dca = ioat3_dca_init(pdev, iobase); - break; - default: - err = -ENODEV; - break; - } - if (!device->dma) - err = -ENODEV; - return err; -} - -static void ioat_shutdown_functionality(struct pci_dev *pdev) -{ - struct ioat_device *device = pci_get_drvdata(pdev); - - dev_err(&pdev->dev, "Removing dma and dca services\n"); - if (device->dca) { - unregister_dca_provider(device->dca); - free_dca_provider(device->dca); - device->dca = NULL; - } - - if (device->dma) { - ioat_dma_remove(device->dma); - device->dma = NULL; - } -} - static struct pci_driver ioat_pci_driver = { .name = "ioatdma", .id_table = ioat_pci_tbl, .probe = ioat_probe, - .shutdown = ioat_shutdown_functionality, .remove = __devexit_p(ioat_remove), }; @@ -179,7 +129,29 @@ static int __devinit ioat_probe(struct pci_dev *pdev, pci_set_master(pdev); - err = ioat_setup_functionality(pdev, iobase); + switch (readb(iobase + IOAT_VER_OFFSET)) { + case IOAT_VER_1_2: + device->dma = ioat_dma_probe(pdev, iobase); + if (device->dma && ioat_dca_enabled) + device->dca = ioat_dca_init(pdev, iobase); + break; + case IOAT_VER_2_0: + device->dma = ioat_dma_probe(pdev, iobase); + if (device->dma && ioat_dca_enabled) + device->dca = ioat2_dca_init(pdev, iobase); + break; + case IOAT_VER_3_0: + device->dma = ioat_dma_probe(pdev, iobase); + if (device->dma && ioat_dca_enabled) + device->dca = ioat3_dca_init(pdev, iobase); + break; + default: + err = -ENODEV; + break; + } + if (!device->dma) + err = -ENODEV; + if (err) goto err_version; @@ -198,17 +170,21 @@ err_enable_device: return err; } -/* - * It is unsafe to remove this module: if removed while a requested - * dma is outstanding, esp. from tcp, it is possible to hang while - * waiting for something that will never finish. However, if you're - * feeling lucky, this usually works just fine. - */ static void __devexit ioat_remove(struct pci_dev *pdev) { struct ioat_device *device = pci_get_drvdata(pdev); - ioat_shutdown_functionality(pdev); + dev_err(&pdev->dev, "Removing dma and dca services\n"); + if (device->dca) { + unregister_dca_provider(device->dca); + free_dca_provider(device->dca); + device->dca = NULL; + } + + if (device->dma) { + ioat_dma_remove(device->dma); + device->dma = NULL; + } kfree(device); } diff --git a/drivers/dma/ioat_dma.c b/drivers/dma/ioat_dma.c index 6607fdd..b3759c4 100644 --- a/drivers/dma/ioat_dma.c +++ b/drivers/dma/ioat_dma.c @@ -734,8 +734,7 @@ static void ioat2_dma_massage_chan_desc(struct ioat_dma_chan *ioat_chan) * ioat_dma_alloc_chan_resources - returns the number of allocated descriptors * @chan: the channel to be filled out */ -static int ioat_dma_alloc_chan_resources(struct dma_chan *chan, - struct dma_client *client) +static int ioat_dma_alloc_chan_resources(struct dma_chan *chan) { struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan); struct ioat_desc_sw *desc; @@ -1341,12 +1340,11 @@ static void ioat_dma_start_null_desc(struct ioat_dma_chan *ioat_chan) */ #define IOAT_TEST_SIZE 2000 -DECLARE_COMPLETION(test_completion); static void ioat_dma_test_callback(void *dma_async_param) { - printk(KERN_ERR "ioatdma: ioat_dma_test_callback(%p)\n", - dma_async_param); - complete(&test_completion); + struct completion *cmp = dma_async_param; + + complete(cmp); } /** @@ -1363,6 +1361,7 @@ static int ioat_dma_self_test(struct ioatdma_device *device) dma_addr_t dma_dest, dma_src; dma_cookie_t cookie; int err = 0; + struct completion cmp; src = kzalloc(sizeof(u8) * IOAT_TEST_SIZE, GFP_KERNEL); if (!src) @@ -1381,7 +1380,7 @@ static int ioat_dma_self_test(struct ioatdma_device *device) dma_chan = container_of(device->common.channels.next, struct dma_chan, device_node); - if (device->common.device_alloc_chan_resources(dma_chan, NULL) < 1) { + if (device->common.device_alloc_chan_resources(dma_chan) < 1) { dev_err(&device->pdev->dev, "selftest cannot allocate chan resource\n"); err = -ENODEV; @@ -1402,8 +1401,9 @@ static int ioat_dma_self_test(struct ioatdma_device *device) } async_tx_ack(tx); + init_completion(&cmp); tx->callback = ioat_dma_test_callback; - tx->callback_param = (void *)0x8086; + tx->callback_param = &cmp; cookie = tx->tx_submit(tx); if (cookie < 0) { dev_err(&device->pdev->dev, @@ -1413,7 +1413,7 @@ static int ioat_dma_self_test(struct ioatdma_device *device) } device->common.device_issue_pending(dma_chan); - wait_for_completion_timeout(&test_completion, msecs_to_jiffies(3000)); + wait_for_completion_timeout(&cmp, msecs_to_jiffies(3000)); if (device->common.device_is_tx_complete(dma_chan, cookie, NULL, NULL) != DMA_SUCCESS) { diff --git a/drivers/dma/iop-adma.c b/drivers/dma/iop-adma.c index 6be3172..ea5440d 100644 --- a/drivers/dma/iop-adma.c +++ b/drivers/dma/iop-adma.c @@ -24,7 +24,6 @@ #include <linux/init.h> #include <linux/module.h> -#include <linux/async_tx.h> #include <linux/delay.h> #include <linux/dma-mapping.h> #include <linux/spinlock.h> @@ -116,7 +115,7 @@ iop_adma_run_tx_complete_actions(struct iop_adma_desc_slot *desc, } /* run dependent operations */ - async_tx_run_dependencies(&desc->async_tx); + dma_run_dependencies(&desc->async_tx); return cookie; } @@ -270,8 +269,6 @@ static void __iop_adma_slot_cleanup(struct iop_adma_chan *iop_chan) break; } - BUG_ON(!seen_current); - if (cookie > 0) { iop_chan->completed_cookie = cookie; pr_debug("\tcompleted cookie %d\n", cookie); @@ -471,8 +468,7 @@ static void iop_chan_start_null_xor(struct iop_adma_chan *iop_chan); * greater than 2x the number slots needed to satisfy a device->max_xor * request. * */ -static int iop_adma_alloc_chan_resources(struct dma_chan *chan, - struct dma_client *client) +static int iop_adma_alloc_chan_resources(struct dma_chan *chan) { char *hw_desc; int idx; @@ -866,7 +862,7 @@ static int __devinit iop_adma_memcpy_self_test(struct iop_adma_device *device) dma_chan = container_of(device->common.channels.next, struct dma_chan, device_node); - if (iop_adma_alloc_chan_resources(dma_chan, NULL) < 1) { + if (iop_adma_alloc_chan_resources(dma_chan) < 1) { err = -ENODEV; goto out; } @@ -964,7 +960,7 @@ iop_adma_xor_zero_sum_self_test(struct iop_adma_device *device) dma_chan = container_of(device->common.channels.next, struct dma_chan, device_node); - if (iop_adma_alloc_chan_resources(dma_chan, NULL) < 1) { + if (iop_adma_alloc_chan_resources(dma_chan) < 1) { err = -ENODEV; goto out; } @@ -1115,26 +1111,13 @@ static int __devexit iop_adma_remove(struct platform_device *dev) struct iop_adma_device *device = platform_get_drvdata(dev); struct dma_chan *chan, *_chan; struct iop_adma_chan *iop_chan; - int i; struct iop_adma_platform_data *plat_data = dev->dev.platform_data; dma_async_device_unregister(&device->common); - for (i = 0; i < 3; i++) { - unsigned int irq; - irq = platform_get_irq(dev, i); - free_irq(irq, device); - } - dma_free_coherent(&dev->dev, plat_data->pool_size, device->dma_desc_pool_virt, device->dma_desc_pool); - do { - struct resource *res; - res = platform_get_resource(dev, IORESOURCE_MEM, 0); - release_mem_region(res->start, res->end - res->start); - } while (0); - list_for_each_entry_safe(chan, _chan, &device->common.channels, device_node) { iop_chan = to_iop_adma_chan(chan); @@ -1255,7 +1238,6 @@ static int __devinit iop_adma_probe(struct platform_device *pdev) spin_lock_init(&iop_chan->lock); INIT_LIST_HEAD(&iop_chan->chain); INIT_LIST_HEAD(&iop_chan->all_slots); - INIT_RCU_HEAD(&iop_chan->common.rcu); iop_chan->common.device = dma_dev; list_add_tail(&iop_chan->common.device_node, &dma_dev->channels); @@ -1431,16 +1413,12 @@ static int __init iop_adma_init (void) return platform_driver_register(&iop_adma_driver); } -/* it's currently unsafe to unload this module */ -#if 0 static void __exit iop_adma_exit (void) { platform_driver_unregister(&iop_adma_driver); return; } module_exit(iop_adma_exit); -#endif - module_init(iop_adma_init); MODULE_AUTHOR("Intel Corporation"); diff --git a/drivers/dma/mv_xor.c b/drivers/dma/mv_xor.c index bcda174..d35cbd1 100644 --- a/drivers/dma/mv_xor.c +++ b/drivers/dma/mv_xor.c @@ -18,7 +18,6 @@ #include <linux/init.h> #include <linux/module.h> -#include <linux/async_tx.h> #include <linux/delay.h> #include <linux/dma-mapping.h> #include <linux/spinlock.h> @@ -340,7 +339,7 @@ mv_xor_run_tx_complete_actions(struct mv_xor_desc_slot *desc, } /* run dependent operations */ - async_tx_run_dependencies(&desc->async_tx); + dma_run_dependencies(&desc->async_tx); return cookie; } @@ -607,8 +606,7 @@ submit_done: } /* returns the number of allocated descriptors */ -static int mv_xor_alloc_chan_resources(struct dma_chan *chan, - struct dma_client *client) +static int mv_xor_alloc_chan_resources(struct dma_chan *chan) { char *hw_desc; int idx; @@ -958,7 +956,7 @@ static int __devinit mv_xor_memcpy_self_test(struct mv_xor_device *device) dma_chan = container_of(device->common.channels.next, struct dma_chan, device_node); - if (mv_xor_alloc_chan_resources(dma_chan, NULL) < 1) { + if (mv_xor_alloc_chan_resources(dma_chan) < 1) { err = -ENODEV; goto out; } @@ -1053,7 +1051,7 @@ mv_xor_xor_self_test(struct mv_xor_device *device) dma_chan = container_of(device->common.channels.next, struct dma_chan, device_node); - if (mv_xor_alloc_chan_resources(dma_chan, NULL) < 1) { + if (mv_xor_alloc_chan_resources(dma_chan) < 1) { err = -ENODEV; goto out; } @@ -1221,7 +1219,6 @@ static int __devinit mv_xor_probe(struct platform_device *pdev) INIT_LIST_HEAD(&mv_chan->chain); INIT_LIST_HEAD(&mv_chan->completed_slots); INIT_LIST_HEAD(&mv_chan->all_slots); - INIT_RCU_HEAD(&mv_chan->common.rcu); mv_chan->common.device = dma_dev; list_add_tail(&mv_chan->common.device_node, &dma_dev->channels); diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c index 1e97916..76bfe16 100644 --- a/drivers/mmc/host/atmel-mci.c +++ b/drivers/mmc/host/atmel-mci.c @@ -55,7 +55,6 @@ enum atmel_mci_state { struct atmel_mci_dma { #ifdef CONFIG_MMC_ATMELMCI_DMA - struct dma_client client; struct dma_chan *chan; struct dma_async_tx_descriptor *data_desc; #endif @@ -593,10 +592,8 @@ atmci_submit_data_dma(struct atmel_mci *host, struct mmc_data *data) /* If we don't have a channel, we can't do DMA */ chan = host->dma.chan; - if (chan) { - dma_chan_get(chan); + if (chan) host->data_chan = chan; - } if (!chan) return -ENODEV; @@ -1443,60 +1440,6 @@ static irqreturn_t atmci_detect_interrupt(int irq, void *dev_id) return IRQ_HANDLED; } -#ifdef CONFIG_MMC_ATMELMCI_DMA - -static inline struct atmel_mci * -dma_client_to_atmel_mci(struct dma_client *client) -{ - return container_of(client, struct atmel_mci, dma.client); -} - -static enum dma_state_client atmci_dma_event(struct dma_client *client, - struct dma_chan *chan, enum dma_state state) -{ - struct atmel_mci *host; - enum dma_state_client ret = DMA_NAK; - - host = dma_client_to_atmel_mci(client); - - switch (state) { - case DMA_RESOURCE_AVAILABLE: - spin_lock_bh(&host->lock); - if (!host->dma.chan) { - host->dma.chan = chan; - ret = DMA_ACK; - } - spin_unlock_bh(&host->lock); - - if (ret == DMA_ACK) - dev_info(&host->pdev->dev, - "Using %s for DMA transfers\n", - chan->dev.bus_id); - break; - - case DMA_RESOURCE_REMOVED: - spin_lock_bh(&host->lock); - if (host->dma.chan == chan) { - host->dma.chan = NULL; - ret = DMA_ACK; - } - spin_unlock_bh(&host->lock); - - if (ret == DMA_ACK) - dev_info(&host->pdev->dev, - "Lost %s, falling back to PIO\n", - chan->dev.bus_id); - break; - - default: - break; - } - - - return ret; -} -#endif /* CONFIG_MMC_ATMELMCI_DMA */ - static int __init atmci_init_slot(struct atmel_mci *host, struct mci_slot_pdata *slot_data, unsigned int id, u32 sdc_reg) @@ -1600,6 +1543,18 @@ static void __exit atmci_cleanup_slot(struct atmel_mci_slot *slot, mmc_free_host(slot->mmc); } +#ifdef CONFIG_MMC_ATMELMCI_DMA +static bool filter(struct dma_chan *chan, void *slave) +{ + struct dw_dma_slave *dws = slave; + + if (dws->dma_dev == chan->device->dev) + return true; + else + return false; +} +#endif + static int __init atmci_probe(struct platform_device *pdev) { struct mci_platform_data *pdata; @@ -1652,22 +1607,20 @@ static int __init atmci_probe(struct platform_device *pdev) goto err_request_irq; #ifdef CONFIG_MMC_ATMELMCI_DMA - if (pdata->dma_slave) { - struct dma_slave *slave = pdata->dma_slave; + if (pdata->dma_slave.dma_dev) { + struct dw_dma_slave *dws = &pdata->dma_slave; + dma_cap_mask_t mask; - slave->tx_reg = regs->start + MCI_TDR; - slave->rx_reg = regs->start + MCI_RDR; + dws->tx_reg = regs->start + MCI_TDR; + dws->rx_reg = regs->start + MCI_RDR; /* Try to grab a DMA channel */ - host->dma.client.event_callback = atmci_dma_event; - dma_cap_set(DMA_SLAVE, host->dma.client.cap_mask); - host->dma.client.slave = slave; - - dma_async_client_register(&host->dma.client); - dma_async_client_chan_request(&host->dma.client); - } else { - dev_notice(&pdev->dev, "DMA not available, using PIO\n"); + dma_cap_zero(mask); + dma_cap_set(DMA_SLAVE, mask); + host->dma.chan = dma_request_channel(mask, filter, dws); } + if (!host->dma.chan) + dev_notice(&pdev->dev, "DMA not available, using PIO\n"); #endif /* CONFIG_MMC_ATMELMCI_DMA */ platform_set_drvdata(pdev, host); @@ -1699,8 +1652,8 @@ static int __init atmci_probe(struct platform_device *pdev) err_init_slot: #ifdef CONFIG_MMC_ATMELMCI_DMA - if (pdata->dma_slave) - dma_async_client_unregister(&host->dma.client); + if (host->dma.chan) + dma_release_channel(host->dma.chan); #endif free_irq(irq, host); err_request_irq: @@ -1731,8 +1684,8 @@ static int __exit atmci_remove(struct platform_device *pdev) clk_disable(host->mck); #ifdef CONFIG_MMC_ATMELMCI_DMA - if (host->dma.client.slave) - dma_async_client_unregister(&host->dma.client); + if (host->dma.chan) + dma_release_channel(host->dma.chan); #endif free_irq(platform_get_irq(pdev, 0), host); @@ -1761,7 +1714,7 @@ static void __exit atmci_exit(void) platform_driver_unregister(&atmci_driver); } -module_init(atmci_init); +late_initcall(atmci_init); /* try to load after dma driver when built-in */ module_exit(atmci_exit); MODULE_DESCRIPTION("Atmel Multimedia Card Interface driver"); diff --git a/include/linux/async_tx.h b/include/linux/async_tx.h index 0f50d4c..45f6297 100644 --- a/include/linux/async_tx.h +++ b/include/linux/async_tx.h @@ -59,9 +59,7 @@ enum async_tx_flags { }; #ifdef CONFIG_DMA_ENGINE -void async_tx_issue_pending_all(void); -enum dma_status dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx); -void async_tx_run_dependencies(struct dma_async_tx_descriptor *tx); +#define async_tx_issue_pending_all dma_issue_pending_all #ifdef CONFIG_ARCH_HAS_ASYNC_TX_FIND_CHANNEL #include <asm/async_tx.h> #else @@ -77,19 +75,6 @@ static inline void async_tx_issue_pending_all(void) do { } while (0); } -static inline enum dma_status -dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx) -{ - return DMA_SUCCESS; -} - -static inline void -async_tx_run_dependencies(struct dma_async_tx_descriptor *tx, - struct dma_chan *host_chan) -{ - do { } while (0); -} - static inline struct dma_chan * async_tx_find_channel(struct dma_async_tx_descriptor *depend_tx, enum dma_transaction_type tx_type, struct page **dst, int dst_count, diff --git a/include/linux/atmel-mci.h b/include/linux/atmel-mci.h index 2a2213e..2f1f957 100644 --- a/include/linux/atmel-mci.h +++ b/include/linux/atmel-mci.h @@ -3,7 +3,7 @@ #define ATMEL_MCI_MAX_NR_SLOTS 2 -struct dma_slave; +#include <linux/dw_dmac.h> /** * struct mci_slot_pdata - board-specific per-slot configuration @@ -28,11 +28,11 @@ struct mci_slot_pdata { /** * struct mci_platform_data - board-specific MMC/SDcard configuration - * @dma_slave: DMA slave interface to use in data transfers, or NULL. + * @dma_slave: DMA slave interface to use in data transfers. * @slot: Per-slot configuration data. */ struct mci_platform_data { - struct dma_slave *dma_slave; + struct dw_dma_slave dma_slave; struct mci_slot_pdata slot[ATMEL_MCI_MAX_NR_SLOTS]; }; diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h index adb0b08..64dea2a 100644 --- a/include/linux/dmaengine.h +++ b/include/linux/dmaengine.h @@ -29,32 +29,6 @@ #include <linux/dma-mapping.h> /** - * enum dma_state - resource PNP/power management state - * @DMA_RESOURCE_SUSPEND: DMA device going into low power state - * @DMA_RESOURCE_RESUME: DMA device returning to full power - * @DMA_RESOURCE_AVAILABLE: DMA device available to the system - * @DMA_RESOURCE_REMOVED: DMA device removed from the system - */ -enum dma_state { - DMA_RESOURCE_SUSPEND, - DMA_RESOURCE_RESUME, - DMA_RESOURCE_AVAILABLE, - DMA_RESOURCE_REMOVED, -}; - -/** - * enum dma_state_client - state of the channel in the client - * @DMA_ACK: client would like to use, or was using this channel - * @DMA_DUP: client has already seen this channel, or is not using this channel - * @DMA_NAK: client does not want to see any more channels - */ -enum dma_state_client { - DMA_ACK, - DMA_DUP, - DMA_NAK, -}; - -/** * typedef dma_cookie_t - an opaque DMA cookie * * if dma_cookie_t is >0 it's a DMA request cookie, <0 it's an error code @@ -89,23 +63,13 @@ enum dma_transaction_type { DMA_MEMSET, DMA_MEMCPY_CRC32C, DMA_INTERRUPT, + DMA_PRIVATE, DMA_SLAVE, }; /* last transaction type for creation of the capabilities mask */ #define DMA_TX_TYPE_END (DMA_SLAVE + 1) -/** - * enum dma_slave_width - DMA slave register access width. - * @DMA_SLAVE_WIDTH_8BIT: Do 8-bit slave register accesses - * @DMA_SLAVE_WIDTH_16BIT: Do 16-bit slave register accesses - * @DMA_SLAVE_WIDTH_32BIT: Do 32-bit slave register accesses - */ -enum dma_slave_width { - DMA_SLAVE_WIDTH_8BIT, - DMA_SLAVE_WIDTH_16BIT, - DMA_SLAVE_WIDTH_32BIT, -}; /** * enum dma_ctrl_flags - DMA flags to augment operation preparation, @@ -132,32 +96,6 @@ enum dma_ctrl_flags { typedef struct { DECLARE_BITMAP(bits, DMA_TX_TYPE_END); } dma_cap_mask_t; /** - * struct dma_slave - Information about a DMA slave - * @dev: device acting as DMA slave - * @dma_dev: required DMA master device. If non-NULL, the client can not be - * bound to other masters than this. - * @tx_reg: physical address of data register used for - * memory-to-peripheral transfers - * @rx_reg: physical address of data register used for - * peripheral-to-memory transfers - * @reg_width: peripheral register width - * - * If dma_dev is non-NULL, the client can not be bound to other DMA - * masters than the one corresponding to this device. The DMA master - * driver may use this to determine if there is controller-specific - * data wrapped around this struct. Drivers of platform code that sets - * the dma_dev field must therefore make sure to use an appropriate - * controller-specific dma slave structure wrapping this struct. - */ -struct dma_slave { - struct device *dev; - struct device *dma_dev; - dma_addr_t tx_reg; - dma_addr_t rx_reg; - enum dma_slave_width reg_width; -}; - -/** * struct dma_chan_percpu - the per-CPU part of struct dma_chan * @refcount: local_t used for open-coded "bigref" counting * @memcpy_count: transaction counter @@ -165,7 +103,6 @@ struct dma_slave { */ struct dma_chan_percpu { - local_t refcount; /* stats */ unsigned long memcpy_count; unsigned long bytes_transferred; @@ -176,13 +113,14 @@ struct dma_chan_percpu { * @device: ptr to the dma device who supplies this channel, always !%NULL * @cookie: last cookie value returned to client * @chan_id: channel ID for sysfs - * @class_dev: class device for sysfs + * @dev: class device for sysfs * @refcount: kref, used in "bigref" slow-mode * @slow_ref: indicates that the DMA channel is free * @rcu: the DMA channel's RCU head * @device_node: used to add this to the device chan list * @local: per-cpu pointer to a struct dma_chan_percpu * @client-count: how many clients are using this channel + * @table_count: number of appearances in the mem-to-mem allocation table */ struct dma_chan { struct dma_device *device; @@ -190,73 +128,47 @@ struct dma_chan { /* sysfs */ int chan_id; - struct device dev; - - struct kref refcount; - int slow_ref; - struct rcu_head rcu; + struct dma_chan_dev *dev; struct list_head device_node; struct dma_chan_percpu *local; int client_count; + int table_count; }; -#define to_dma_chan(p) container_of(p, struct dma_chan, dev) - -void dma_chan_cleanup(struct kref *kref); - -static inline void dma_chan_get(struct dma_chan *chan) -{ - if (unlikely(chan->slow_ref)) - kref_get(&chan->refcount); - else { - local_inc(&(per_cpu_ptr(chan->local, get_cpu())->refcount)); - put_cpu(); - } -} +/** + * struct dma_chan_dev - relate sysfs device node to backing channel device + * @chan - driver channel device + * @device - sysfs device + * @dev_id - parent dma_device dev_id + * @idr_ref - reference count to gate release of dma_device dev_id + */ +struct dma_chan_dev { + struct dma_chan *chan; + struct device device; + int dev_id; + atomic_t *idr_ref; +}; -static inline void dma_chan_put(struct dma_chan *chan) +static inline const char *dma_chan_name(struct dma_chan *chan) { - if (unlikely(chan->slow_ref)) - kref_put(&chan->refcount, dma_chan_cleanup); - else { - local_dec(&(per_cpu_ptr(chan->local, get_cpu())->refcount)); - put_cpu(); - } + return dev_name(&chan->dev->device); } -/* - * typedef dma_event_callback - function pointer to a DMA event callback - * For each channel added to the system this routine is called for each client. - * If the client would like to use the channel it returns '1' to signal (ack) - * the dmaengine core to take out a reference on the channel and its - * corresponding device. A client must not 'ack' an available channel more - * than once. When a channel is removed all clients are notified. If a client - * is using the channel it must 'ack' the removal. A client must not 'ack' a - * removed channel more than once. - * @client - 'this' pointer for the client context - * @chan - channel to be acted upon - * @state - available or removed - */ -struct dma_client; -typedef enum dma_state_client (*dma_event_callback) (struct dma_client *client, - struct dma_chan *chan, enum dma_state state); +void dma_chan_cleanup(struct kref *kref); /** - * struct dma_client - info on the entity making use of DMA services - * @event_callback: func ptr to call when something happens - * @cap_mask: only return channels that satisfy the requested capabilities - * a value of zero corresponds to any capability - * @slave: data for preparing slave transfer. Must be non-NULL iff the - * DMA_SLAVE capability is requested. - * @global_node: list_head for global dma_client_list + * typedef dma_filter_fn - callback filter for dma_request_channel + * @chan: channel to be reviewed + * @filter_param: opaque parameter passed through dma_request_channel + * + * When this optional parameter is specified in a call to dma_request_channel a + * suitable channel is passed to this routine for further dispositioning before + * being returned. Where 'suitable' indicates a non-busy channel that + * satisfies the given capability mask. It returns 'true' to indicate that the + * channel is suitable. */ -struct dma_client { - dma_event_callback event_callback; - dma_cap_mask_t cap_mask; - struct dma_slave *slave; - struct list_head global_node; -}; +typedef bool (*dma_filter_fn)(struct dma_chan *chan, void *filter_param); typedef void (*dma_async_tx_callback)(void *dma_async_param); /** @@ -323,14 +235,10 @@ struct dma_device { dma_cap_mask_t cap_mask; int max_xor; - struct kref refcount; - struct completion done; - int dev_id; struct device *dev; - int (*device_alloc_chan_resources)(struct dma_chan *chan, - struct dma_client *client); + int (*device_alloc_chan_resources)(struct dma_chan *chan); void (*device_free_chan_resources)(struct dma_chan *chan); struct dma_async_tx_descriptor *(*device_prep_dma_memcpy)( @@ -362,9 +270,8 @@ struct dma_device { /* --- public DMA engine API --- */ -void dma_async_client_register(struct dma_client *client); -void dma_async_client_unregister(struct dma_client *client); -void dma_async_client_chan_request(struct dma_client *client); +void dmaengine_get(void); +void dmaengine_put(void); dma_cookie_t dma_async_memcpy_buf_to_buf(struct dma_chan *chan, void *dest, void *src, size_t len); dma_cookie_t dma_async_memcpy_buf_to_pg(struct dma_chan *chan, @@ -406,6 +313,12 @@ __dma_cap_set(enum dma_transaction_type tx_type, dma_cap_mask_t *dstp) set_bit(tx_type, dstp->bits); } +#define dma_cap_zero(mask) __dma_cap_zero(&(mask)) +static inline void __dma_cap_zero(dma_cap_mask_t *dstp) +{ + bitmap_zero(dstp->bits, DMA_TX_TYPE_END); +} + #define dma_has_cap(tx, mask) __dma_has_cap((tx), &(mask)) static inline int __dma_has_cap(enum dma_transaction_type tx_type, dma_cap_mask_t *srcp) @@ -475,11 +388,25 @@ static inline enum dma_status dma_async_is_complete(dma_cookie_t cookie, } enum dma_status dma_sync_wait(struct dma_chan *chan, dma_cookie_t cookie); +#ifdef CONFIG_DMA_ENGINE +enum dma_status dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx); +#else +static inline enum dma_status dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx) +{ + return DMA_SUCCESS; +} +#endif /* --- DMA device --- */ int dma_async_device_register(struct dma_device *device); void dma_async_device_unregister(struct dma_device *device); +void dma_run_dependencies(struct dma_async_tx_descriptor *tx); +struct dma_chan *dma_find_channel(enum dma_transaction_type tx_type); +void dma_issue_pending_all(void); +#define dma_request_channel(mask, x, y) __dma_request_channel(&(mask), x, y) +struct dma_chan *__dma_request_channel(dma_cap_mask_t *mask, dma_filter_fn fn, void *fn_param); +void dma_release_channel(struct dma_chan *chan); /* --- Helper iov-locking functions --- */ diff --git a/include/linux/dw_dmac.h b/include/linux/dw_dmac.h index 04d217b..d797dde 100644 --- a/include/linux/dw_dmac.h +++ b/include/linux/dw_dmac.h @@ -22,14 +22,34 @@ struct dw_dma_platform_data { }; /** + * enum dw_dma_slave_width - DMA slave register access width. + * @DMA_SLAVE_WIDTH_8BIT: Do 8-bit slave register accesses + * @DMA_SLAVE_WIDTH_16BIT: Do 16-bit slave register accesses + * @DMA_SLAVE_WIDTH_32BIT: Do 32-bit slave register accesses + */ +enum dw_dma_slave_width { + DW_DMA_SLAVE_WIDTH_8BIT, + DW_DMA_SLAVE_WIDTH_16BIT, + DW_DMA_SLAVE_WIDTH_32BIT, +}; + +/** * struct dw_dma_slave - Controller-specific information about a slave - * @slave: Generic information about the slave - * @ctl_lo: Platform-specific initializer for the CTL_LO register + * + * @dma_dev: required DMA master device + * @tx_reg: physical address of data register used for + * memory-to-peripheral transfers + * @rx_reg: physical address of data register used for + * peripheral-to-memory transfers + * @reg_width: peripheral register width * @cfg_hi: Platform-specific initializer for the CFG_HI register * @cfg_lo: Platform-specific initializer for the CFG_LO register */ struct dw_dma_slave { - struct dma_slave slave; + struct device *dma_dev; + dma_addr_t tx_reg; + dma_addr_t rx_reg; + enum dw_dma_slave_width reg_width; u32 cfg_hi; u32 cfg_lo; }; @@ -54,9 +74,4 @@ struct dw_dma_slave { #define DWC_CFGL_HS_DST_POL (1 << 18) /* dst handshake active low */ #define DWC_CFGL_HS_SRC_POL (1 << 19) /* src handshake active low */ -static inline struct dw_dma_slave *to_dw_dma_slave(struct dma_slave *slave) -{ - return container_of(slave, struct dw_dma_slave, slave); -} - #endif /* DW_DMAC_H */ diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 114091b..f245568 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -1125,9 +1125,6 @@ struct softnet_data struct sk_buff *completion_queue; struct napi_struct backlog; -#ifdef CONFIG_NET_DMA - struct dma_chan *net_dma; -#endif }; DECLARE_PER_CPU(struct softnet_data,softnet_data); diff --git a/include/net/netdma.h b/include/net/netdma.h index f28c6e0..8ba8ce2 100644 --- a/include/net/netdma.h +++ b/include/net/netdma.h @@ -24,17 +24,6 @@ #include <linux/dmaengine.h> #include <linux/skbuff.h> -static inline struct dma_chan *get_softnet_dma(void) -{ - struct dma_chan *chan; - rcu_read_lock(); - chan = rcu_dereference(__get_cpu_var(softnet_data).net_dma); - if (chan) - dma_chan_get(chan); - rcu_read_unlock(); - return chan; -} - int dma_skb_copy_datagram_iovec(struct dma_chan* chan, struct sk_buff *skb, int offset, struct iovec *to, size_t len, struct dma_pinned_list *pinned_list); diff --git a/net/core/dev.c b/net/core/dev.c index bab8bce..5f736f1 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -170,25 +170,6 @@ static DEFINE_SPINLOCK(ptype_lock); static struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly; static struct list_head ptype_all __read_mostly; /* Taps */ -#ifdef CONFIG_NET_DMA -struct net_dma { - struct dma_client client; - spinlock_t lock; - cpumask_t channel_mask; - struct dma_chan **channels; -}; - -static enum dma_state_client -netdev_dma_event(struct dma_client *client, struct dma_chan *chan, - enum dma_state state); - -static struct net_dma net_dma = { - .client = { - .event_callback = netdev_dma_event, - }, -}; -#endif - /* * The @dev_base_head list is protected by @dev_base_lock and the rtnl * semaphore. @@ -2754,14 +2735,7 @@ out: * There may not be any more sk_buffs coming right now, so push * any pending DMA copies to hardware */ - if (!cpus_empty(net_dma.channel_mask)) { - int chan_idx; - for_each_cpu_mask_nr(chan_idx, net_dma.channel_mask) { - struct dma_chan *chan = net_dma.channels[chan_idx]; - if (chan) - dma_async_memcpy_issue_pending(chan); - } - } + dma_issue_pending_all(); #endif return; @@ -4952,122 +4926,6 @@ static int dev_cpu_callback(struct notifier_block *nfb, return NOTIFY_OK; } -#ifdef CONFIG_NET_DMA -/** - * net_dma_rebalance - try to maintain one DMA channel per CPU - * @net_dma: DMA client and associated data (lock, channels, channel_mask) - * - * This is called when the number of channels allocated to the net_dma client - * changes. The net_dma client tries to have one DMA channel per CPU. - */ - -static void net_dma_rebalance(struct net_dma *net_dma) -{ - unsigned int cpu, i, n, chan_idx; - struct dma_chan *chan; - - if (cpus_empty(net_dma->channel_mask)) { - for_each_online_cpu(cpu) - rcu_assign_pointer(per_cpu(softnet_data, cpu).net_dma, NULL); - return; - } - - i = 0; - cpu = first_cpu(cpu_online_map); - - for_each_cpu_mask_nr(chan_idx, net_dma->channel_mask) { - chan = net_dma->channels[chan_idx]; - - n = ((num_online_cpus() / cpus_weight(net_dma->channel_mask)) - + (i < (num_online_cpus() % - cpus_weight(net_dma->channel_mask)) ? 1 : 0)); - - while(n) { - per_cpu(softnet_data, cpu).net_dma = chan; - cpu = next_cpu(cpu, cpu_online_map); - n--; - } - i++; - } -} - -/** - * netdev_dma_event - event callback for the net_dma_client - * @client: should always be net_dma_client - * @chan: DMA channel for the event - * @state: DMA state to be handled - */ -static enum dma_state_client -netdev_dma_event(struct dma_client *client, struct dma_chan *chan, - enum dma_state state) -{ - int i, found = 0, pos = -1; - struct net_dma *net_dma = - container_of(client, struct net_dma, client); - enum dma_state_client ack = DMA_DUP; /* default: take no action */ - - spin_lock(&net_dma->lock); - switch (state) { - case DMA_RESOURCE_AVAILABLE: - for (i = 0; i < nr_cpu_ids; i++) - if (net_dma->channels[i] == chan) { - found = 1; - break; - } else if (net_dma->channels[i] == NULL && pos < 0) - pos = i; - - if (!found && pos >= 0) { - ack = DMA_ACK; - net_dma->channels[pos] = chan; - cpu_set(pos, net_dma->channel_mask); - net_dma_rebalance(net_dma); - } - break; - case DMA_RESOURCE_REMOVED: - for (i = 0; i < nr_cpu_ids; i++) - if (net_dma->channels[i] == chan) { - found = 1; - pos = i; - break; - } - - if (found) { - ack = DMA_ACK; - cpu_clear(pos, net_dma->channel_mask); - net_dma->channels[i] = NULL; - net_dma_rebalance(net_dma); - } - break; - default: - break; - } - spin_unlock(&net_dma->lock); - - return ack; -} - -/** - * netdev_dma_register - register the networking subsystem as a DMA client - */ -static int __init netdev_dma_register(void) -{ - net_dma.channels = kzalloc(nr_cpu_ids * sizeof(struct net_dma), - GFP_KERNEL); - if (unlikely(!net_dma.channels)) { - printk(KERN_NOTICE - "netdev_dma: no memory for net_dma.channels\n"); - return -ENOMEM; - } - spin_lock_init(&net_dma.lock); - dma_cap_set(DMA_MEMCPY, net_dma.client.cap_mask); - dma_async_client_register(&net_dma.client); - dma_async_client_chan_request(&net_dma.client); - return 0; -} - -#else -static int __init netdev_dma_register(void) { return -ENODEV; } -#endif /* CONFIG_NET_DMA */ /** * netdev_increment_features - increment feature set by one @@ -5287,14 +5145,15 @@ static int __init net_dev_init(void) if (register_pernet_device(&default_device_ops)) goto out; - netdev_dma_register(); - open_softirq(NET_TX_SOFTIRQ, net_tx_action); open_softirq(NET_RX_SOFTIRQ, net_rx_action); hotcpu_notifier(dev_cpu_callback, 0); dst_init(); dev_mcast_init(); + #ifdef CONFIG_NET_DMA + dmaengine_get(); + #endif rc = 0; out: return rc; diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index bd6ff90..ce572f9 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -1313,7 +1313,7 @@ int tcp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, if ((available < target) && (len > sysctl_tcp_dma_copybreak) && !(flags & MSG_PEEK) && !sysctl_tcp_low_latency && - __get_cpu_var(softnet_data).net_dma) { + dma_find_channel(DMA_MEMCPY)) { preempt_enable_no_resched(); tp->ucopy.pinned_list = dma_pin_iovec_pages(msg->msg_iov, len); @@ -1523,7 +1523,7 @@ do_prequeue: if (!(flags & MSG_TRUNC)) { #ifdef CONFIG_NET_DMA if (!tp->ucopy.dma_chan && tp->ucopy.pinned_list) - tp->ucopy.dma_chan = get_softnet_dma(); + tp->ucopy.dma_chan = dma_find_channel(DMA_MEMCPY); if (tp->ucopy.dma_chan) { tp->ucopy.dma_cookie = dma_skb_copy_datagram_iovec( @@ -1628,7 +1628,6 @@ skip_copy: /* Safe to free early-copied skbs now */ __skb_queue_purge(&sk->sk_async_wait_queue); - dma_chan_put(tp->ucopy.dma_chan); tp->ucopy.dma_chan = NULL; } if (tp->ucopy.pinned_list) { diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 99b7ecb..a6961d7 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -5005,7 +5005,7 @@ static int tcp_dma_try_early_copy(struct sock *sk, struct sk_buff *skb, return 0; if (!tp->ucopy.dma_chan && tp->ucopy.pinned_list) - tp->ucopy.dma_chan = get_softnet_dma(); + tp->ucopy.dma_chan = dma_find_channel(DMA_MEMCPY); if (tp->ucopy.dma_chan && skb_csum_unnecessary(skb)) { diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 9d839fa..19d7b42 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -1594,7 +1594,7 @@ process: #ifdef CONFIG_NET_DMA struct tcp_sock *tp = tcp_sk(sk); if (!tp->ucopy.dma_chan && tp->ucopy.pinned_list) - tp->ucopy.dma_chan = get_softnet_dma(); + tp->ucopy.dma_chan = dma_find_channel(DMA_MEMCPY); if (tp->ucopy.dma_chan) ret = tcp_v4_do_rcv(sk, skb); else diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index 1297306..e5b85d4 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -1675,7 +1675,7 @@ process: #ifdef CONFIG_NET_DMA struct tcp_sock *tp = tcp_sk(sk); if (!tp->ucopy.dma_chan && tp->ucopy.pinned_list) - tp->ucopy.dma_chan = get_softnet_dma(); + tp->ucopy.dma_chan = dma_find_channel(DMA_MEMCPY); if (tp->ucopy.dma_chan) ret = tcp_v6_do_rcv(sk, skb); else |