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path: root/drivers/block
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2008-04-28return pfn from direct_access, for XIPJared Hulbert
Alter the block device ->direct_access() API to work with the new get_xip_mem() API (that requires both kaddr and pfn are returned). Some architectures will not do the right thing in their virt_to_page() for use by XIP (to translate from the kernel virtual address returned by direct_access(), to a user mappable pfn in XIP's page fault handler. However, we can't switch it to just return the pfn and not the kaddr, because we have no good way to get a kva from a pfn, and XIP requires the kva for its read(2) and write(2) handlers. So we have to return both. Signed-off-by: Jared Hulbert <jaredeh@gmail.com> Signed-off-by: Nick Piggin <npiggin@suse.de> Cc: Carsten Otte <cotte@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: linux-mm@kvack.org Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-24xen: Add compatibility aliases for frontend driversMark McLoughlin
Before getting merged, xen-blkfront was xenblk and xen-netfront was xennet. Temporarily adding compatibility module aliases eases upgrades from older versions by e.g. allowing mkinitrd to find the new version of the module. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-24xen: Module autoprobing support for frontend driversMark McLoughlin
Add module aliases to support autoprobing modules for xen frontend devices. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-24xen blkfront: Delay wait for block devices until after the disk is addedChristian Limpach
When the xen block frontend driver is built as a module the module load is only synchronous up to the point where the frontend and the backend become connected rather than when the disk is added. This means that there can be a race on boot between loading the module and loading the dm-* modules and doing the scan for LVM physical volumes (all in the initrd). In the failure case the disk is not present until after the scan for physical volumes is complete. Taken from: http://xenbits.xensource.com/linux-2.6.18-xen.hg?rev/11483a00c017 Signed-off-by: Christian Limpach <Christian.Limpach@xensource.com> Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-24xen/blkfront: use bdget_diskJeremy Fitzhardinge
info->dev is never initialized to anything, so bdget(info->dev) is meaningless. Get rid of info->dev, and use bdget_disk on the gendisk. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Cc: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-24xen: Make xen-blkfront write its protocol ABI to xenstoreMarkus Armbruster
Frontends are expected to write their protocol ABI to xenstore. Since the protocol ABI defaults to the backend's native ABI, things work fine without that as long as the frontend's native ABI is identical to the backend's native ABI. This is not the case for xen-blkfront running 32-on-64, because its ABI differs between 32 and 64 bit, and thus needs this fix. Based on http://xenbits.xensource.com/xen-unstable.hg?rev/c545932a18f3 and http://xenbits.xensource.com/xen-unstable.hg?rev/ffe52263b430 by Gerd Hoffmann <kraxel@suse.de> Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Jeremy Fitzhardinge <Jeremy.Fitzhardinge@citrix.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-22fix brd allocation flagsPetr Tesarik
While looking at the implementation of the Ram backed block device driver, I stumbled across a write-only local variable, which makes little sense, so I assume it should actually work like this: Signed-off-by: Petr Tesarik <ptesarik@suse.cz> Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-21Merge branch 'for-2.6.26' of git://git.kernel.dk/linux-2.6-blockLinus Torvalds
* 'for-2.6.26' of git://git.kernel.dk/linux-2.6-block: block: fix blk_register_queue() return value block: fix memory hotplug and bouncing in block layer block: replace remaining __FUNCTION__ occurrences Kconfig: clean up block/Kconfig help descriptions cciss: fix warning oops on rmmod of driver cciss: Fix race between disk-adding code and interrupt handler block: move the padding adjustment to blk_rq_map_sg block: add bio_copy_user_iov support to blk_rq_map_user_iov block: convert bio_copy_user to bio_copy_user_iov loop: manage partitions in disk image cdrom: use kmalloced buffers instead of buffers on stack cdrom: make unregister_cdrom() return void cdrom: use list_head for cdrom_device_info list cdrom: protect cdrom_device_info list by mutex cdrom: cleanup hardcoded error-code cdrom: remove ifdef CONFIG_SYSCTL
2008-04-21Merge branch 'master' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc * 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc: (202 commits) [POWERPC] Fix compile breakage for 64-bit UP configs [POWERPC] Define copy_siginfo_from_user32 [POWERPC] Add compat handler for PTRACE_GETSIGINFO [POWERPC] i2c: Fix build breakage introduced by OF helpers [POWERPC] Optimize fls64() on 64-bit processors [POWERPC] irqtrace support for 64-bit powerpc [POWERPC] Stacktrace support for lockdep [POWERPC] Move stackframe definitions to common header [POWERPC] Fix device-tree locking vs. interrupts [POWERPC] Make pci_bus_to_host()'s struct pci_bus * argument const [POWERPC] Remove unused __max_memory variable [POWERPC] Simplify xics direct/lpar irq_host setup [POWERPC] Use pseries_setup_i8259_cascade() in pseries_mpic_init_IRQ() [POWERPC] Turn xics_setup_8259_cascade() into a generic pseries_setup_i8259_cascade() [POWERPC] Move xics_setup_8259_cascade() into platforms/pseries/setup.c [POWERPC] Use asm-generic/bitops/find.h in bitops.h [POWERPC] 83xx: mpc8315 - fix USB UTMI Host setup [POWERPC] 85xx: Fix the size of qe muram for MPC8568E [POWERPC] 86xx: mpc86xx_hpcn - Temporarily accept old dts node identifier. [POWERPC] 86xx: mark functions static, other minor cleanups ...
2008-04-21block: replace remaining __FUNCTION__ occurrencesHarvey Harrison
__FUNCTION__ is gcc-specific, use __func__ Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Cc: Jens Axboe <jens.axboe@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-04-21cciss: fix warning oops on rmmod of driverscameron@beardog.cca.cpqcorp.net
* Fix oops on cciss rmmod due to calling pci_free_consistent with irqs disabled. Signed-off-by: Stephen M. Cameron <scameron@beardog.cca.cpqcorp.net> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-04-21cciss: Fix race between disk-adding code and interrupt handlerscameron@beardog.cca.cpqcorp.net
Fix race condition between cciss_init_one(), cciss_update_drive_info(), and cciss_check_queues(). Signed-off-by: Stephen M. Cameron <scameron@beardog.cca.cpqcorp.net> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-04-21loop: manage partitions in disk imageLaurent Vivier
This patch allows to use loop device with partitionned disk image. Original behavior of loop is not modified. A new parameter is introduced to define how many partition we want to be able to manage per loop device. This parameter is "max_part". For instance, to manage 63 partitions / loop device, we will do: # modprobe loop max_part=63 # ls -l /dev/loop?* brw-rw---- 1 root disk 7, 0 2008-03-05 14:55 /dev/loop0 brw-rw---- 1 root disk 7, 64 2008-03-05 14:55 /dev/loop1 brw-rw---- 1 root disk 7, 128 2008-03-05 14:55 /dev/loop2 brw-rw---- 1 root disk 7, 192 2008-03-05 14:55 /dev/loop3 brw-rw---- 1 root disk 7, 256 2008-03-05 14:55 /dev/loop4 brw-rw---- 1 root disk 7, 320 2008-03-05 14:55 /dev/loop5 brw-rw---- 1 root disk 7, 384 2008-03-05 14:55 /dev/loop6 brw-rw---- 1 root disk 7, 448 2008-03-05 14:55 /dev/loop7 And to attach a raw partitionned disk image, the original losetup is used: # losetup -f etch.img # ls -l /dev/loop?* brw-rw---- 1 root disk 7, 0 2008-03-05 14:55 /dev/loop0 brw-rw---- 1 root disk 7, 1 2008-03-05 14:57 /dev/loop0p1 brw-rw---- 1 root disk 7, 2 2008-03-05 14:57 /dev/loop0p2 brw-rw---- 1 root disk 7, 5 2008-03-05 14:57 /dev/loop0p5 brw-rw---- 1 root disk 7, 64 2008-03-05 14:55 /dev/loop1 brw-rw---- 1 root disk 7, 128 2008-03-05 14:55 /dev/loop2 brw-rw---- 1 root disk 7, 192 2008-03-05 14:55 /dev/loop3 brw-rw---- 1 root disk 7, 256 2008-03-05 14:55 /dev/loop4 brw-rw---- 1 root disk 7, 320 2008-03-05 14:55 /dev/loop5 brw-rw---- 1 root disk 7, 384 2008-03-05 14:55 /dev/loop6 brw-rw---- 1 root disk 7, 448 2008-03-05 14:55 /dev/loop7 # mount /dev/loop0p1 /mnt # ls /mnt bench cdrom home lib mnt root srv usr bin dev initrd lost+found opt sbin sys var boot etc initrd.img media proc selinux tmp vmlinuz # umount /mnt # losetup -d /dev/loop0 Of course, the same behavior can be done using kpartx on a loop device, but modifying loop avoids to stack several layers of block device (loop + device mapper), this is a very light modification (40% of modifications are to manage the new parameter). Signed-off-by: Laurent Vivier <Laurent.Vivier@bull.net> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-04-19drivers: Remove unnecessary inclusions of asm/semaphore.hMatthew Wilcox
None of these files use any of the functionality promised by asm/semaphore.h. It's possible that they rely on it dragging in some unrelated header file, but I can't build all these files, so we'll have fix any build failures as they come up. Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
2008-04-18Merge branch 'master' of ↵David S. Miller
master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6
2008-04-14Merge branch 'linux-2.6'Paul Mackerras
2008-04-11cciss: error: implicit declaration of function 'sg_init_table'Mike Pagano
This patch adds the missing include directive <linux/scatterlist.h> to the cciss.c source file.   This was discovered by our release team when building the kernel for the Alpha architecture. Errors were found as references to functions 'sg_init_table' and 'sg_page' do not exist without the include for Alpha. Signed-off-by: Mike Pagano <mpagano@gentoo.org> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: <mike.miller@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-09ub: remove BUG() after __blk_end_request and fix the condition causing itPete Zaitcev
When __blk_end_request returns nonzero, it means that the request was not completely processed and some BIOs are still attached. Since we have dequeued it by that time, it means leaking requests and hanging processes, which is why BUG() was in there. In ub this happens if a packet request ends normally, but with residue (e.g. when scsi_id issues INQUIRY). The fix is to make sure that arguments passed to __blk_end_request are correct: the full request length and not just transferred length. The transferred length is indicated to applications by adjusting rq->data_len with old, unchanged code outside of this patch. Signed-off-by: Pete Zaitcev <zaitcev@redhat.com> Cc: Kiyoshi Ueda <k-ueda@ct.jp.nec.com> Cc: Greg KH <greg@kroah.com> Cc: Boaz Harrosh <bharrosh@panasas.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-03Merge branch 'master' of ↵David S. Miller
git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
2008-04-02nbd: prevent sock_xmit from attempting to use a NULL socketMike Snitzer
NBD does not protect the nbd_device's socket from becoming NULL during receives. This closes a race with the NBD_CLEAR_SOCK ioctl (nbd-client -d) setting the nbd_device's socket to NULL right before NBD calls sock_xmit. Signed-off-by: Mike Snitzer <snitzer@gmail.com> Cc: Paul Clements <paul.clements@steeleye.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-01[POWERPC] Use FIELD_SIZEOF in drivers/block/viodasd.cJulia Lawall
Robert P.J. Day proposed to use the macro FIELD_SIZEOF in replace of code that matches its definition. The modification was made using the following semantic patch (http://www.emn.fr/x-info/coccinelle/) // <smpl> @haskernel@ @@ #include <linux/kernel.h> @depends on haskernel@ type t; identifier f; @@ - (sizeof(((t*)0)->f)) + FIELD_SIZEOF(t, f) @depends on haskernel@ type t; identifier f; @@ - sizeof(((t*)0)->f) + FIELD_SIZEOF(t, f) // </smpl> Signed-off-by: Julia Lawall <julia@diku.dk> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-03-25[NET] NETNS: Omit net_device->nd_net without CONFIG_NET_NS.YOSHIFUJI Hideaki
Introduce per-net_device inlines: dev_net(), dev_net_set(). Without CONFIG_NET_NS, no namespace other than &init_net exists. Let's explicitly define them to help compiler optimizations. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
2008-03-18Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-blockLinus Torvalds
* 'for-linus' of git://git.kernel.dk/linux-2.6-block: Revert "unexport bio_{,un}map_user" relay: fix subbuf_splice_actor() adding too many pages The ps2esdi driver was marked as BROKEN more than two years ago due to being
2008-03-17virtio: Fix sysfs bits to have proper block symlinkJeremy Katz
Fix up so that the virtio_blk devices in sysfs link correctly to their block device. This then allows them to be detected by hal, etc Signed-off-by: Jeremy Katz <katzj@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-03-17The ps2esdi driver was marked as BROKEN more than two years ago due to beingAdrian Bunk
no longer working for some time. A driver that had been marked as BROKEN for such a long time seems to be unlikely to be revived in the forseeable future. But if anyone wants to ever revive this driver, the code is still present in the older kernel releases. Signed-off-by: Adrian Bunk <bunk@kernel.org> Acked-by: Alan Cox <alan@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-03-13block: floppy: fix rmmod lockupJiri Slaby
Floppy rmmod locks up when no such hardware was initialized, since there is nobody to wake the remove code up. Remove the completion, because release is called during platform_unregister anyway. Signed-off-by: Jiri Slaby <jirislaby@gmail.com> Cc: Jens Axboe <jens.axboe@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-03-12[POWERPC] Fix viodasd driver with scatterlist debugBenjamin Herrenschmidt
The iSeries viodasd drivers does some very strange things with scatterlists, one of these causing a BUG_ON to trigger when scatterlist debugging is enabled due to initializing the scatterlist with memset instead of sg_init_table(). This fixes it by using sg_init_table(). The rest of the stuff it does to that poor list is still pretty awful but it will work. I may look into fixing things in a nicer way some other time. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-03-05pktcdvd: reduce stack consumptionPeter Osterlund
On my system, pkt_open() consumes 584 bytes because the compiler decides to inline lots of functions that would not normally be part of long call chains. The following patch fixes that problem on my system. Signed-off-by: Peter Osterlund <petero2@telia.com> Cc: Nix <nix@esperi.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-03-04cciss: remove READ_AHEAD define and use block layer defaultsMike Miller
This patch removes the #define READ_AHEAD 1024 from the driver and uses the block layer defaults, instead. We have found that under certain workloads the setting can cause a disk connected to the e200 controller to go offline. If the disk hiccups the link may try to downshift but the controller is never notified that the link successfully completed the renegotiation. We've also found that performance using the block layer default of 32 pages was on par with the 1024 setting. We tried setting it to zero at one time based on info from our firmware guys but that killed performance. Turns out we were talking about 2 different read ahead settings. Please consider this for inclusion. Signed-off-by: Mike Miller <mike.miller@hp.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-03-04resubmit: cciss: procfs updates to display info about manyMike Miller
volumes This patch allows us to display information about all of the logical volumes configured on a particular controller without stepping on memory even when there are many volumes (128 or more) configured. Please consider this for inclusion. Signed-off-by: Mike Miller <mike.miller@hp.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-02-24NBD: make nbd default to deadline I/O schedulerPaul Clements
NBD doesn't work well with CFQ (or AS) schedulers, so let's default to something else. The two problems I have experienced with nbd and cfq are: 1) nbd hangs with cfq on RHEL 5 (2.6.18) -- this may well have been fixed There's a similar debian bug that has been filed as well: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=447638 There have been posts to nbd-general mailing list about problems with cfq and nbd also. 2) nbd performs about 10% better (the last time I tested) with deadline vs. cfq (the overhead of cfq doesn't provide much advantage to nbd [not being a real disk], and you end up going through the I/O scheduler on the nbd server anyway, so it makes sense that deadline is better with nbd) Signed-off-by: Paul Clements <paul.clements@steeleye.com> Cc: Jens Axboe <jens.axboe@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-22xen: Implement getgeo for Xen virtual block device.Ian Campbell
The below implements the getgeo hook for Xen block devices. Extracted from the xen-unstable tree where it has been used for ages. It is useful to have because it allows things like grub2 (used by the Debian installer images) to work in a guest domain without having to sprinkle Xen specific hacks around the place. Signed-off-by: Ian Campbell <ijc@hellion.org.uk> Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-15Fix compile of swim3 as moduleTony Breeds
The current pmac32_defconfig fails to build with the following error: Building modules, stage 2. ERROR: "check_media_bay" [drivers/block/swim3.ko] undefined! WARNING: modpost: Found 23 section mismatch(es). To see full details build your kernel with: 'make CONFIG_DEBUG_SECTION_MISMATCH=y' make[2]: *** [__modpost] Error 1 This patch fixes that. Signed-off-by: Tony Breeds <tony@bakeyournoodle.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Acked-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com> Cc: Josh Boyer <jwboyer@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-09ub: fix up the conversion to sg_init_table()Pete Zaitcev
Signed-off-by: Pete Zaitcev <zaitcev@redhat.com> Cc: "Oliver Pinter" <oliver.pntr@gmail.com> Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-blockLinus Torvalds
* 'for-linus' of git://git.kernel.dk/linux-2.6-block: Enhanced partition statistics: documentation update Enhanced partition statistics: remove old partition statistics Enhanced partition statistics: procfs Enhanced partition statistics: sysfs Enhanced partition statistics: aoe fix Enhanced partition statistics: update partition statitics Enhanced partition statistics: core statistics block: fixup rq_init() a bit Manually fixed conflict in drivers/block/aoe/aoecmd.c due to statistics support.
2008-02-08NBD: remove limit on max number of nbd devicesPaul Clements
Remove the arbitrary 128 device limit for NBD. nbds_max can now be set to any number. In certain scenarios where devices are used sparsely we have run into the 128 device limit. Signed-off-by: Paul Clements <paul.clements@steeleye.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08aoe: statically initialise devlist_lockAndrew Morton
I guess aoedev_init() can go away now. Cc: Greg KH <greg@kroah.com> Cc: "Ed L. Cashin" <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08aoe: update copyright dateEd L. Cashin
Update the year in the copyright notices. Signed-off-by: Ed L. Cashin <ecashin@coraid.com> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08aoe: make error messages more specificEd L. Cashin
Andrew Morton pointed out that the "too many targets" message in patch 2 could be printed for failing GFP_ATOMIC allocations. This patch makes the messages more specific. Signed-off-by: Ed L. Cashin <ecashin@coraid.com> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08aoe: the aoeminor doesn't need a long formatEd L. Cashin
The aoedev aoeminor member doesn't need a long format. Signed-off-by: Ed L. Cashin <ecashin@coraid.com> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08aoe: add module parameter for users who need more outstanding I/OEd L. Cashin
An AoE target provides an estimate of the number of outstanding commands that the AoE initiator can send before getting a response. The aoe_maxout parameter provides a way to set an even lower limit. It will not allow a user to use more outstanding commands than the target permits. If a user discovers a problem with a large setting, this parameter provides a way for us to work with them to debug the problem. We expect to improve the dynamic window sizing algorithm and drop this parameter. For the time being, it is a debugging aid. Signed-off-by: Ed L. Cashin <ecashin@coraid.com> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08aoe: only install new AoE device onceEd L. Cashin
An aoe driver user who had about 70 AoE targets found that he was hitting a BUG in sysfs_create_file because the aoe driver was trying to tell the kernel about an AoE device more than once. Each AoE device was reachable by several local network interfaces, and multiple ATA device indentify responses were returning from that single device. This patch eliminates a race condition so that aoe always informs the block layer of a new AoE device once in the presence of multiple incoming ATA device identify responses. Signed-off-by: Ed L. Cashin <ecashin@coraid.com> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08aoe: dynamically allocate a capped number of skbs when necessaryEd L. Cashin
What this Patch Does Even before this recent series of 12 patches to 2.6.22-rc4, the aoe driver was reusing a small set of skbs that were allocated once and were only used for outbound AoE commands. The network layer cannot be allowed to put_page on the data that is still associated with a bio we haven't returned to the block layer, so the aoe driver (even before the patch under discussion) is still the owner of skbs that have been handed to the network layer for transmission. We need to keep track of these skbs so that we can free them, but by tracking them, we can also easily re-use them. The new patch was a response to the behavior of certain network drivers. We cannot reuse an skb that the network driver still has in its transmit ring. Network drivers can defer transmit ring cleanup and then use the state in the skb to determine how many data segments to clean up in its transmit ring. The tg3 driver is one driver that behaves in this way. When the network driver defers cleanup of its transmit ring, the aoe driver can find itself in a situation where it would like to send an AoE command, and the AoE target is ready for more work, but the network driver still has all of the pre-allocated skbs. In that case, the new patch just calls alloc_skb, as you'd expect. We don't want to get carried away, though. We try not to do excessive allocation in the write path, so we cap the number of skbs we dynamically allocate. Probably calling it a "dynamic pool" is misleading. We were already trying to use a small fixed-size set of pre-allocated skbs before this patch, and this patch just provides a little headroom (with a ceiling, though) to accomodate network drivers that hang onto skbs, by allocating when needed. The d->skbpool_hd list of allocated skbs is necessary so that we can free them later. We didn't notice the need for this headroom until AoE targets got fast enough. Alternatives If the network layer never did a put_page on the pages in the bio's we get from the block layer, then it would be possible for us to hand skbs to the network layer and forget about them, allowing the network layer to free skbs itself (and thereby calling our own skb->destructor callback function if we needed that). In that case we could get rid of the pre-allocated skbs and also the d->skbpool_hd, instead just calling alloc_skb every time we wanted to transmit a packet. The slab allocator would effectively maintain the list of skbs. Besides a loss of CPU cache locality, the main concern with that approach the danger that it would increase the likelihood of deadlock when VM is trying to free pages by writing dirty data from the page cache through the aoe driver out to persistent storage on an AoE device. Right now we have a situation where we have pre-allocation that corresponds to how much we use, which seems ideal. Of course, there's still the separate issue of receiving the packets that tell us that a write has successfully completed on the AoE target. When memory is low and VM is using AoE to flush dirty data to free up pages, it would be perfect if there were a way for us to register a fast callback that could recognize write command completion responses. But I don't think the current problems with the receive side of the situation are a justification for exacerbating the problem on the transmit side. Signed-off-by: Ed L. Cashin <ecashin@coraid.com> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08aoe: user can ask driver to forget previously detected devicesEd L. Cashin
When an AoE device is detected, the kernel is informed, and a new block device is created. If the device is unused, the block device corresponding to remote device that is no longer available may be removed from the system by telling the aoe driver to "flush" its list of devices. Without this patch, software like GPFS and LVM may attempt to read from AoE devices that were discovered earlier but are no longer present, blocking until the I/O attempt times out. Signed-off-by: Ed L. Cashin <ecashin@coraid.com> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08aoe: eliminate goto and improve readabilityEd L. Cashin
Adam Richter suggested eliminating this goto. Signed-off-by: Ed L. Cashin <ecashin@coraid.com> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08aoe: mac_addr: avoid 64-bit arch compiler warningsEd L. Cashin
By returning unsigned long long, mac_addr does not generate compiler warnings on 64-bit architectures. Signed-off-by: Ed L. Cashin <ecashin@coraid.com> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08aoe: handle multiple network paths to AoE deviceEd L. Cashin
A remote AoE device is something can process ATA commands and is identified by an AoE shelf number and an AoE slot number. Such a device might have more than one network interface, and it might be reachable by more than one local network interface. This patch tracks the available network paths available to each AoE device, allowing them to be used more efficiently. Andrew Morton asked about the call to msleep_interruptible in the revalidate function. Yes, if a signal is pending, then msleep_interruptible will not return 0. That means we will not loop but will call aoenet_xmit with a NULL skb, which is a noop. If the system is too low on memory or the aoe driver is too low on frames, then the user can hit control-C to interrupt the attempt to do a revalidate. I have added a comment to the code summarizing that. Andrew Morton asked whether the allocation performed inside addtgt could use a more relaxed allocation like GFP_KERNEL, but addtgt is called when the aoedev lock has been locked with spin_lock_irqsave. It would be nice to allocate the memory under fewer restrictions, but targets are only added when the device is being discovered, and if the target can't be added right now, we can try again in a minute when then next AoE config query broadcast goes out. Andrew Morton pointed out that the "too many targets" message could be printed for failing GFP_ATOMIC allocations. The last patch in this series makes the messages more specific. Signed-off-by: Ed L. Cashin <ecashin@coraid.com> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08aoe: bring driver version number to 47Ed L. Cashin
Signed-off-by: Ed L. Cashin <ecashin@coraid.com> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08rd: support XIPNick Piggin
Support direct_access XIP method with brd. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08rewrite rdNick Piggin
This is a rewrite of the ramdisk block device driver. The old one is really difficult because it effectively implements a block device which serves data out of its own buffer cache. It relies on the dirty bit being set, to pin its backing store in cache, however there are non trivial paths which can clear the dirty bit (eg. try_to_free_buffers()), which had recently lead to data corruption. And in general it is completely wrong for a block device driver to do this. The new one is more like a regular block device driver. It has no idea about vm/vfs stuff. It's backing store is similar to the buffer cache (a simple radix-tree of pages), but it doesn't know anything about page cache (the pages in the radix tree are not pagecache pages). There is one slight downside -- direct block device access and filesystem metadata access goes through an extra copy and gets stored in RAM twice. However, this downside is only slight, because the real buffercache of the device is now reclaimable (because we're not playing crazy games with it), so under memory intensive situations, footprint should effectively be the same -- maybe even a slight advantage to the new driver because it can also reclaim buffer heads. The fact that it now goes through all the regular vm/fs paths makes it much more useful for testing, too. text data bss dec hex filename 2837 849 384 4070 fe6 drivers/block/rd.o 3528 371 12 3911 f47 drivers/block/brd.o Text is larger, but data and bss are smaller, making total size smaller. A few other nice things about it: - Similar structure and layout to the new loop device handlinag. - Dynamic ramdisk creation. - Runtime flexible buffer head size (because it is no longer part of the ramdisk code). - Boot / load time flexible ramdisk size, which could easily be extended to a per-ramdisk runtime changeable size (eg. with an ioctl). - Can use highmem for the backing store. [akpm@linux-foundation.org: fix build] [byron.bbradley@gmail.com: make rd_size non-static] Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Byron Bradley <byron.bbradley@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>