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path: root/drivers/block/aoe
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2013-09-11aoe: update copyright dateEd Cashin
Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11aoe: fill in per-AoE-target information for debugfs fileEd Cashin
This information is presented in a compact format that has evolved for easy routine scanning by expert humans, mostly developers and support technicians helping to troubleshoot or test AoE-based systems. Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11aoe: provide file operations for debugfs filesEd Cashin
The place holder in the file contents is filled out in the following patch. Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11aoe: add AoE-target files to debugfsEd Cashin
Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11aoe: create and destroy debugfs directory for aoeEd Cashin
This series adds the debugging information that the coraid.com-distributed aoe driver exports via sysfs, but instead of sysfs, it uses debugfs. With these patches applied, even without AoE targets on the network, KEDR reports new possible memory leaks, but these are from callers outside the aoe driver that have used aoe_devnode to get the name of the character devices through the aoe_class->devnode callback, and I believe they're responsible for freeing that memory. This patch: Create and destroy the debugfs directory. Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-08-13aoe: adjust ref of head for compound page tailsEd Cashin
Fix a BUG which can trigger when direct-IO is used with AOE. As discussed previously, the fact that some users of the block layer provide bios that point to pages with a zero _count means that it is not OK for the network layer to do a put_page on the skb frags during an skb_linearize, so the aoe driver gets a reference to pages in bios and puts the reference before ending the bio. And because it cannot use get_page on a page with a zero _count, it manipulates the value directly. It is not OK to increment the _count of a compound page tail, though, since the VM layer will VM_BUG_ON a non-zero _count. Block users that do direct I/O can result in the aoe driver seeing compound page tails in bios. In that case, the same logic works as long as the head of the compound page is used instead of the tails. This patch handles compound pages and does not BUG. It relies on the block layer user leaving the relationship between the page tail and its head alone for the duration between the submission of the bio and its completion, whether successful or not. Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03aoe: update internal version number to v83Ed Cashin
Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03aoe: update copyright dateEd Cashin
Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03aoe: perform I/O completions in parallelEd Cashin
Some users have a large AoE target while others like to use many AoE targets at the same time. In the latter case, there is an opportunity to greatly improve aggregate throughput by allowing different threads to complete the I/O associated with each target. For 36 targets, 4 KiB read throughput roughly doubles, for example, with these changes in place. Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03drivers: avoid parsing names as kthread_run() format stringsKees Cook
Calling kthread_run with a single name parameter causes it to be handled as a format string. Many callers are passing potentially dynamic string content, so use "%s" in those cases to avoid any potential accidents. Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-08Merge branch 'for-3.10/drivers' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block driver updates from Jens Axboe: "It might look big in volume, but when categorized, not a lot of drivers are touched. The pull request contains: - mtip32xx fixes from Micron. - A slew of drbd updates, this time in a nicer series. - bcache, a flash/ssd caching framework from Kent. - Fixes for cciss" * 'for-3.10/drivers' of git://git.kernel.dk/linux-block: (66 commits) bcache: Use bd_link_disk_holder() bcache: Allocator cleanup/fixes cciss: bug fix to prevent cciss from loading in kdump crash kernel cciss: add cciss_allow_hpsa module parameter drivers/block/mg_disk.c: add CONFIG_PM_SLEEP to suspend/resume functions mtip32xx: Workaround for unaligned writes bcache: Make sure blocksize isn't smaller than device blocksize bcache: Fix merge_bvec_fn usage for when it modifies the bvm bcache: Correctly check against BIO_MAX_PAGES bcache: Hack around stuff that clones up to bi_max_vecs bcache: Set ra_pages based on backing device's ra_pages bcache: Take data offset from the bdev superblock. mtip32xx: mtip32xx: Disable TRIM support mtip32xx: fix a smatch warning bcache: Disable broken btree fuzz tester bcache: Fix a format string overflow bcache: Fix a minor memory leak on device teardown bcache: Documentation updates bcache: Use WARN_ONCE() instead of __WARN() bcache: Add missing #include <linux/prefetch.h> ...
2013-05-08Merge branch 'for-3.10/core' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block core updates from Jens Axboe: - Major bit is Kents prep work for immutable bio vecs. - Stable candidate fix for a scheduling-while-atomic in the queue bypass operation. - Fix for the hang on exceeded rq->datalen 32-bit unsigned when merging discard bios. - Tejuns changes to convert the writeback thread pool to the generic workqueue mechanism. - Runtime PM framework, SCSI patches exists on top of these in James' tree. - A few random fixes. * 'for-3.10/core' of git://git.kernel.dk/linux-block: (40 commits) relay: move remove_buf_file inside relay_close_buf partitions/efi.c: replace useless kzalloc's by kmalloc's fs/block_dev.c: fix iov_shorten() criteria in blkdev_aio_read() block: fix max discard sectors limit blkcg: fix "scheduling while atomic" in blk_queue_bypass_start Documentation: cfq-iosched: update documentation help for cfq tunables writeback: expose the bdi_wq workqueue writeback: replace custom worker pool implementation with unbound workqueue writeback: remove unused bdi_pending_list aoe: Fix unitialized var usage bio-integrity: Add explicit field for owner of bip_buf block: Add an explicit bio flag for bios that own their bvec block: Add bio_alloc_pages() block: Convert some code to bio_for_each_segment_all() block: Add bio_for_each_segment_all() bounce: Refactor __blk_queue_bounce to not use bi_io_vec raid1: use bio_copy_data() pktcdvd: Use bio_reset() in disabled code to kill bi_idx usage pktcdvd: use bio_copy_data() block: Add bio_copy_data() ...
2013-05-07block_device_operations->release() should return voidAl Viro
The value passed is 0 in all but "it can never happen" cases (and those only in a couple of drivers) *and* it would've been lost on the way out anyway, even if something tried to pass something meaningful. Just don't bother. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-04-30aoe: replace kmalloc and then memcpy with kmemdupMihnea Dobrescu-Balaur
Signed-off-by: Mihnea Dobrescu-Balaur <mihneadb@gmail.com> Cc: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-03-28aoe: reserve enough headroom on skbsEric Dumazet
Some network drivers use a non default hard_header_len Transmitted skb should take into account dev->hard_header_len, or risk crashes or expensive reallocations. In the case of aoe, lets reserve MAX_HEADER bytes. David reported a crash in defxx driver, solved by this patch. Reported-by: David Oostdyk <daveo@ll.mit.edu> Tested-by: David Oostdyk <daveo@ll.mit.edu> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Ed Cashin <ecashin@coraid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-25aoe: get rid of cached bv variable in bufinit()Jens Axboe
Less error prone if we just kill it, it's only used once anyway. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2013-03-25aoe: Fix unitialized var usageKent Overstreet
Commit 4f2ac93c175c4922bdddbfec6cad94b32cea0070 (block: Remove bi_idx references) accidently removed the bit that set bv - readd that. Signed-off-by: Kent Overstreet <koverstreet@google.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: "Ed L. Cashin" <ecashin@coraid.com> Cc: fengguang.wu@intel.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2013-03-23block: Remove bi_idx referencesKent Overstreet
For immutable bvecs, all bi_idx usage needs to be audited - so here we're removing all the unnecessary uses. Most of these are places where it was being initialized on a bio that was just allocated, a few others are conversions to standard macros. Signed-off-by: Kent Overstreet <koverstreet@google.com> CC: Jens Axboe <axboe@kernel.dk>
2012-12-17aoe: fix use after free in aoedev_by_aoeaddr()Dan Carpenter
We should return NULL on failure instead of returning a freed pointer. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Cc: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17aoe: update internal version number to 81Ed Cashin
This version number is printed to the console on module initialization and is available in sysfs, which is where the userland aoe-version tool looks for it. Signed-off-by: Ed Cashin <ecashin@coraid.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17aoe: identify source of runt AoE packetsEd Cashin
This change only affects experimental AoE storage networks. It modifies the console message about runt packets detected so that the AoE major and minor addresses of the AoE target that generated the runt are mentioned. Signed-off-by: Ed Cashin <ecashin@coraid.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17aoe: allow comma separator in aoe_iflist valueEd Cashin
By default, the aoe driver uses any ethernet interface for AoE, but the aoe_iflist module parameter provides a convenient way to limit AoE traffic to a specific list of local network interfaces. This change allows a list to be specified using the comma character as a separator. For example, modprobe aoe aoe_iflist=eth2,eth3 Before, it was inconvenient to get the quoting right in shell scripts when setting aoe_iflist to have more than one network interface. Signed-off-by: Ed Cashin <ecashin@coraid.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17aoe: allow user to disable target failure timeoutEd Cashin
With this change, the aoe driver treats the value zero as special for the aoe_deadsecs module parameter. Normally, this value specifies the number of seconds during which the driver will continue to attempt retransmits to an unresponsive AoE target. After aoe_deadsecs has elapsed, the aoe driver marks the aoe device as "down" and fails all I/O. The new meaning of an aoe_deadsecs of zero is for the driver to retransmit commands indefinitely. Signed-off-by: Ed Cashin <ecashin@coraid.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17aoe: use dynamic number of remote ports for AoE storage targetEd Cashin
Many AoE targets have four or fewer network ports, but some existing storage devices have many, and the AoE protocol sets no limit. This patch allows the use of more than eight remote MAC addresses per AoE target, while reducing the amount of memory used by the aoe driver in cases where there are many AoE targets with fewer than eight MAC addresses each. Signed-off-by: Ed Cashin <ecashin@coraid.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17aoe: avoid races between device destruction and discoveryEd Cashin
This change avoids a race that could result in a NULL pointer derference following a WARNing from kobject_add_internal, "don't try to register things with the same name in the same directory." The problem was found with a test that forgets and discovers an aoe device in a loop: while test ! -r /tmp/stop; do aoe-flush -a aoe-discover done The race was between aoedev_flush taking aoedevs out of the devlist, allowing a new discovery of the same AoE target to take place before the driver gets around to calling sysfs_remove_group. Fixing that one revealed another race between do_open and add_disk, and this patch avoids that, too. The fix required some care, because for flushing (forgetting) an aoedev, some of the steps must be performed under lock and some must be able to sleep. Also, for discovering a new aoedev, some steps might sleep. The check for a bad aoedev pointer remains from a time when about half of this patch was done, and it was possible for the bdev->bd_disk->private_data to become corrupted. The check should be removed eventually, but it is not expected to add significant overhead, occurring in the aoeblk_open routine. Signed-off-by: Ed Cashin <ecashin@coraid.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17aoe: improve handling of misbehaving network pathsEd Cashin
An AoE target can have multiple network ports used for AoE, and in the aoe driver, those are tracked by the aoetgt struct. These changes allow the aoe driver to handle network paths, or aoetgts, that are not working well, compared to the others. Paths that do not get responses despite the retransmission of AoE commands are marked as "tainted", and non-tainted paths are preferred. Meanwhile, the aoe driver attempts to "probe" the tainted path in the background by issuing reads of LBA 0 that are padded out to full (possibly jumbo-frame) size. If the probes get responses, then the path is "redeemed", and its taint is removed. This mechanism has been shown to be helpful in transparently handling and recovering from real-world network "brown outs" in ways that the earlier "shoot the help-needing target in the head" mechanism could not. Signed-off-by: Ed Cashin <ecashin@coraid.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17aoe: return real minor number for static minorsEd Cashin
The value returned by the static minor device number number allocator is the real minor number, so it must be multiplied by the supported number of partitions per aoedev. Without this fix the support for systems without udev is incomplete, and the few users of aoe on such systems will have surprising results when device nodes names do not match the AoE target. Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17aoe: initialize sysminor to avoid compiler warningEd Cashin
Because the minor_get and related functions use the return values for errors, the compiler doesn't know that sysminor will always either 1) be initialized in aoedev_by_aoeaddr by the call to minor_get, or 2) be unused as the "goto out" is executed. This patch avoids the compiler warning. Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17aoe: make error messages more specific in static minor allocationEd Cashin
For some special-purpose systems where udev isn't present, static allocation of minor numbers is desirable. This update distinguishes different failure scenarios, to help the user understand what went wrong. Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17aoe: remove call to request handler from I/O completionEd Cashin
There is no need to call the request handler function in the I/O completion routine. The user impact of not doing it is a more "nice" aoe driver that is less susceptible to causing soft lockups. Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17aoe: cleanup: correct comment for aoetgt noutEd Cashin
A misplaced comment was attached to the nout member of the aoetgt. This change corrects the comment. Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17aoe: increase default cap on outstanding AoE commands in the networkEd Cashin
The aoe driver will never be waiting for more than aoe_maxout AoE commands from a given remote network port on an AoE target. Increasing the cap increases performance. Users can tighten the setting to reduce the amount of memory used for handling AoE traffic or the network bandwidth used for AoE. Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17aoe: remove vestigial request queue allocationEd Cashin
Before the aoe driver was an I/O request handler, it was a make_request-style block driver. Even so, there was a problem where sysfs expected a request queue to exist, so one was provided in commit 7135a71b19be ("aoe: allocate unused request_queue for sysfs"). During the transition to the request-handler style, a patch was merged that was based on a driver without the noop queue, and the noop queue remained in place after the patch was merged, even though a new functional queue was introduced by the patch, allocated through blk_init_queue. The user impact is a memory leak proportional to the number of AoE targets discovered. This patch removes the memory leak and cleans up vestiges of the old do-nothing queue from the aoeblk_gdalloc function. Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17aoe: copy fallback timing information on destination failoverEd Cashin
Commit f3b8e07af774 ("aoe: commands in retransmit queue use new destination on failure") omits the copying of the coarse-grained time when an AoE command was sent during the failover from one destination MAC address on the AoE target to another. The coarse-grained timing is only used when the system time changes or an unlikely length of time has passed since the sending of the AoE command. Users will not be impacted unless their system clock is very inaccurate or something unusual (e.g., 10 GbE link reset) happens during the period when the aoe driver is handling the failure of a port on the AoE target. Being effected will mean that an AoE target could be considered "down" too eagerly. Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17aoe: update driver-internal version to 64+Ed Cashin
Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17aoe: commands in retransmit queue use new destination on failureEd Cashin
When one remote MAC address isn't working as a destination for AoE commands, the frames used to track information associated with the AoE commands are moved to a new aoetgt (defined by the tuple of {AoE major, AoE minor, target MAC address}). This patch makes sure that the frames on the queue for retransmits that need to be done are updated to use the new destination, so that retransmits will be sent through a working network path. Without this change, packets on the retransmit queue will be needlessly retransmitted to the unresponsive destination MAC, possibly causing premature target failure before there's time for the retransmit timer to run again, decide to retransmit again, and finally update the destination to a working MAC address on the AoE target. Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17aoe: use high-resolution RTTs with fallback to low-resEd Cashin
These changes improve the accuracy of the decision about whether it's time to retransmit an AoE command by using the microsecond-resolution gettimeofday instead of jiffies. Because the system time can jump suddenly, the decision reverts to using jiffies if the high-resolution time difference is relatively large. Otherwise the AoE targets could be considered failed inappropriately. Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17aoe: manipulate aoedev network stats under lockEd Cashin
With this bugfix in place the calculation of the criterion for "lateness" is performed under lock. Without the lock, there is a chance that one of the non-atomic operations performed on the round trip time statistics could be incomplete, such that an incorrect lateness criterion would be calculated. Without this change, the effect of the bug would be rare unecessary but benign retransmissions. Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17aoe: err device: include MAC addresses for unexpected responsesEd Cashin
The /dev/etherd/err character device provides low-level information about normal but sometimes interesting AoE command retransmits and "unexpected responses", i.e., responses for packets that have already been retransmitted. This change adds MAC addresses to the messages about unexpected responses, so that when they occur, it's more easy to determine the network paths to which they belong. Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17aoe: improve network congestion handlingEd Cashin
The aoe driver already had some congestion handling, but it was limited in its ability to cope with the kind of congestion that can arise on more complex networks such as those involving paths through multiple ethernet switches. Some of the lessons from TCP's history of development can be applied to improving the congestion control and avoidance on AoE storage networks. These changes use familar concepts from Van Jacobson's "Congestion Avoidance and Control" paper from '88, without adding significant overhead. This patch depends on an upcoming patch that covers the failover case when AoE commands being retransmitted are transferred from one retransmit queue to another. Another upcoming patch increases the timing accuracy. Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17aoe: provide ATA identify device content to user on requestEd Cashin
Make the aoe driver follow expected behavior when the user uses ioctl to get the ATA device identify information, allowing access to model, serial number, etc. Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17aoe: update driver-internal version number to 60Ed Cashin
Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17aoe: whitespace cleanupEd Cashin
Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17aoe: cleanup: remove unused ata_scnt functionEd Cashin
Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17aoe: "payload" sysfs file exports per-AoE-command data transfer sizeEd Cashin
The userland aoetools package includes an "aoe-stat" command that can display a "payload size" column when the aoe driver exports this information. Users can quickly see what amount of user data is transferred inside each AoE command on the network, network headers excluded. Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17aoe: support larger I/O requests via aoe_maxsectors module paramEd Cashin
The GPFS filesystem is an example of an aoe user that requires the aoe driver to support I/O request sizes larger than the default. Most users will not need large I/O request sizes, because they would need to be split up into multiple AoE commands anyway. Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17aoe: support the forgetting (flushing) of a user-specified AoE targetEd Cashin
Users sometimes want to cause the aoe driver to forget a particular previously discovered device when it is no longer online. The aoetools provide an "aoe-flush" command that users run to perform this administrative task. The changes below provide the support needed in the driver. Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17aoe: update cap on outstanding commands based on config query responseEd Cashin
The ATA over Ethernet config query response contains a "buffer count" field reflecting the AoE target's capacity to buffer incoming AoE commands. By taking the current value of this field into accound, we increase performance throughput or avoid network congestion, when the value has increased or decreased, respectively. Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17aoe: print warning regarding a common reason for dropped transmitsEd Cashin
Dropped transmits are not common, but when they do occur, increasing the transmit queue length often helps. Signed-off-by: Ed Cashin <ecashin@coraid.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17aoe: describe the behavior of the "err" character deviceEd Cashin
Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>