BMC/Intel-BMC/linux.git/block/bio-integrity.c, branch dev-4.3

block: Refuse adding appending a gapped integrity page to a bio

2015-09-11T15:03:45+00:00

This is only theoretical at the moment given that the only subsystems that generate integrity payloads are the block layer itself and the scsi target (which generate well aligned integrity payloads). But when we will expose integrity meta-data to user-space, we'll need to refuse appending a page with a gap (if the queue virtual boundary is set). Signed-off-by: Sagi Grimberg Signed-off-by: Jens Axboe

block: add a bi_error field to struct bio

2015-07-29T14:55:15+00:00

Currently we have two different ways to signal an I/O error on a BIO: (1) by clearing the BIO_UPTODATE flag (2) by returning a Linux errno value to the bi_end_io callback The first one has the drawback of only communicating a single possible error (-EIO), and the second one has the drawback of not beeing persistent when bios are queued up, and are not passed along from child to parent bio in the ever more popular chaining scenario. Having both mechanisms available has the additional drawback of utterly confusing driver authors and introducing bugs where various I/O submitters only deal with one of them, and the others have to add boilerplate code to deal with both kinds of error returns. So add a new bi_error field to store an errno value directly in struct bio and remove the existing mechanisms to clean all this up. Signed-off-by: Christoph Hellwig Reviewed-by: Hannes Reinecke Reviewed-by: NeilBrown Signed-off-by: Jens Axboe

bio integrity: do not assume bio_integrity_pool exists if bioset exists

2015-07-07T13:46:47+00:00

bio_integrity_alloc() and bio_integrity_free() assume that if a bio was allocated from a bioset that that bioset also had its bio_integrity_pool allocated using bioset_integrity_create(). This is a very bad assumption given that bioset_create() and bioset_integrity_create() are completely disjoint. Not all callers of bioset_create() have been trained to also call bioset_integrity_create() -- and they may not care to be. Fix this by falling back to kmalloc'ing 'struct bio_integrity_payload' rather than force all bioset consumers to (wastefully) preallocate a bio_integrity_pool that they very likely won't actually need (given the niche nature of the current block integrity support). Otherwise, a NULL pointer "Kernel BUG" with a trace like the following will be observed (as seen on s390x using zfcp storage) because dm-io doesn't use bioset_integrity_create() when creating its bioset: [ 791.643338] Call Trace: [ 791.643339] ([<00000003df98b848>] 0x3df98b848) [ 791.643341] [<00000000002c5de8>] bio_integrity_alloc+0x48/0xf8 [ 791.643348] [<00000000002c6486>] bio_integrity_prep+0xae/0x2f0 [ 791.643349] [<0000000000371e38>] blk_queue_bio+0x1c8/0x3d8 [ 791.643355] [<000000000036f8d0>] generic_make_request+0xc0/0x100 [ 791.643357] [<000000000036f9b2>] submit_bio+0xa2/0x198 [ 791.643406] [<000003ff801f9774>] dispatch_io+0x15c/0x3b0 [dm_mod] [ 791.643419] [<000003ff801f9b3e>] dm_io+0x176/0x2f0 [dm_mod] [ 791.643423] [<000003ff8074b28a>] do_reads+0x13a/0x1a8 [dm_mirror] [ 791.643425] [<000003ff8074b43a>] do_mirror+0x142/0x298 [dm_mirror] [ 791.643428] [<0000000000154fca>] process_one_work+0x18a/0x3f8 [ 791.643432] [<000000000015598a>] worker_thread+0x132/0x3b0 [ 791.643435] [<000000000015d49a>] kthread+0xd2/0xd8 [ 791.643438] [<00000000005bc0ca>] kernel_thread_starter+0x6/0xc [ 791.643446] [<00000000005bc0c4>] kernel_thread_starter+0x0/0xc Signed-off-by: Mike Snitzer Cc: stable@vger.kernel.org Signed-off-by: Jens Axboe

block: remove management of bi_remaining when restoring original bi_end_io

2015-05-22T14:58:55+00:00

Commit c4cf5261 ("bio: skip atomic inc/dec of ->bi_remaining for non-chains") regressed all existing callers that followed this pattern: 1) saving a bio's original bi_end_io 2) wiring up an intermediate bi_end_io 3) restoring the original bi_end_io from intermediate bi_end_io 4) calling bio_endio() to execute the restored original bi_end_io The regression was due to BIO_CHAIN only ever getting set if bio_inc_remaining() is called. For the above pattern it isn't set until step 3 above (step 2 would've needed to establish BIO_CHAIN). As such the first bio_endio(), in step 2 above, never decremented __bi_remaining before calling the intermediate bi_end_io -- leaving __bi_remaining with the value 1 instead of 0. When bio_inc_remaining() occurred during step 3 it brought it to a value of 2. When the second bio_endio() was called, in step 4 above, it should've called the original bi_end_io but it didn't because there was an extra reference that wasn't dropped (due to atomic operations being optimized away since BIO_CHAIN wasn't set upfront). Fix this issue by removing the __bi_remaining management complexity for all callers that use the above pattern -- bio_chain() is the only interface that _needs_ to be concerned with __bi_remaining. For the above pattern callers just expect the bi_end_io they set to get called! Remove bio_endio_nodec() and also remove all bio_inc_remaining() calls that aren't associated with the bio_chain() interface. Also, the bio_inc_remaining() interface has been moved local to bio.c. Fixes: c4cf5261 ("bio: skip atomic inc/dec of ->bi_remaining for non-chains") Reviewed-by: Christoph Hellwig Reviewed-by: Jan Kara Signed-off-by: Mike Snitzer Signed-off-by: Jens Axboe

block: fix regression where bio_integrity_process uses wrong bio_vec iterator

2014-12-02T15:15:21+00:00

bio integrity handling is broken on a system with LVM layered atop a DIF/DIX SCSI drive because device mapper clones the bio, modifies the clone, and sends the clone to the lower layers for processing. However, the clone bio has bi_vcnt == 0, which means that when the sd driver calls bio_integrity_process to attach DIX data, the for_each_segment_all() call (which uses bi_vcnt) returns immediately and random garbage is sent to the disk on a disk write. The disk of course returns an error. Therefore, teach bio_integrity_process() to use bio_for_each_segment() to iterate the bio_vecs, since the per-bio iterator tracks which bio_vecs are associated with that particular bio. The integrity handling code is effectively part of the "driver" (it's not the bio owner), so it must use the correct iterator function. v2: Fix a compiler warning about abandoned local variables. This patch supersedes "block: bio_integrity_process uses wrong bio_vec iterator". Patch applies against 3.18-rc6. Signed-off-by: Darrick J. Wong Acked-by: Martin K. Petersen Signed-off-by: Jens Axboe

bio-integrity: remove the needless fail handle of bip_slab creating

2014-10-13T21:09:38+00:00

bip_slab is created with SLAB_PANIC, so the fail handler is unneeded. Signed-off-by: Gu Zheng Signed-off-by: Andrew Morton Signed-off-by: Jens Axboe

block: Integrity checksum flag

2014-09-27T15:14:55+00:00

Make the choice of checksum a per-I/O property by introducing a flag that can be inspected by the SCSI layer. There are several reasons for this: 1. It allows us to switch choice of checksum without unloading and reloading the HBA driver. 2. During error recovery we need to be able to tell the HBA that checksums read from disk should not be verified and converted to IP checksums. 3. For error injection purposes we need to be able to write a bad guard tag to storage. Since the storage device only supports T10 CRC we need to be able to disable IP checksum conversion on the HBA. Signed-off-by: Martin K. Petersen Reviewed-by: Sagi Grimberg Signed-off-by: Jens Axboe

block: Relocate bio integrity flags

2014-09-27T15:14:54+00:00

Move flags affecting the integrity code out of the bio bi_flags and into the block integrity payload. Signed-off-by: Martin K. Petersen Reviewed-by: Sagi Grimberg Signed-off-by: Jens Axboe

block: Add prefix to block integrity profile flags

2014-09-27T15:14:51+00:00

Add a BLK_ prefix to the integrity profile flags. Also rename the flags to be more consistent with the generate/verify terminology in the rest of the integrity code. Signed-off-by: Martin K. Petersen Reviewed-by: Christoph Hellwig Reviewed-by: Sagi Grimberg Signed-off-by: Jens Axboe

block: Clean up the code used to generate and verify integrity metadata

2014-09-27T15:14:51+00:00

Instead of the "operate" parameter we pass in a seed value and a pointer to a function that can be used to process the integrity metadata. The generation function is changed to have a return value to fit into this scheme. Signed-off-by: Martin K. Petersen Reviewed-by: Sagi Grimberg Signed-off-by: Jens Axboe