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author | Linus Torvalds <torvalds@linux-foundation.org> | 2014-10-18 20:53:51 +0200 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-10-18 20:53:51 +0200 |
commit | d3dc366bbaf07c125561e90d6da4bb147741101a (patch) | |
tree | 6eb7e79a8ec9df1fa705393c6d15ccea3d104661 /Documentation/block | |
parent | Merge tag 'for-linus-20141015' of git://git.infradead.org/linux-mtd (diff) | |
parent | block: Remove REQ_KERNEL (diff) | |
download | linux-d3dc366bbaf07c125561e90d6da4bb147741101a.tar.xz linux-d3dc366bbaf07c125561e90d6da4bb147741101a.zip |
Merge branch 'for-3.18/core' of git://git.kernel.dk/linux-block
Pull core block layer changes from Jens Axboe:
"This is the core block IO pull request for 3.18. Apart from the new
and improved flush machinery for blk-mq, this is all mostly bug fixes
and cleanups.
- blk-mq timeout updates and fixes from Christoph.
- Removal of REQ_END, also from Christoph. We pass it through the
->queue_rq() hook for blk-mq instead, freeing up one of the request
bits. The space was overly tight on 32-bit, so Martin also killed
REQ_KERNEL since it's no longer used.
- blk integrity updates and fixes from Martin and Gu Zheng.
- Update to the flush machinery for blk-mq from Ming Lei. Now we
have a per hardware context flush request, which both cleans up the
code should scale better for flush intensive workloads on blk-mq.
- Improve the error printing, from Rob Elliott.
- Backing device improvements and cleanups from Tejun.
- Fixup of a misplaced rq_complete() tracepoint from Hannes.
- Make blk_get_request() return error pointers, fixing up issues
where we NULL deref when a device goes bad or missing. From Joe
Lawrence.
- Prep work for drastically reducing the memory consumption of dm
devices from Junichi Nomura. This allows creating clone bio sets
without preallocating a lot of memory.
- Fix a blk-mq hang on certain combinations of queue depths and
hardware queues from me.
- Limit memory consumption for blk-mq devices for crash dump
scenarios and drivers that use crazy high depths (certain SCSI
shared tag setups). We now just use a single queue and limited
depth for that"
* 'for-3.18/core' of git://git.kernel.dk/linux-block: (58 commits)
block: Remove REQ_KERNEL
blk-mq: allocate cpumask on the home node
bio-integrity: remove the needless fail handle of bip_slab creating
block: include func name in __get_request prints
block: make blk_update_request print prefix match ratelimited prefix
blk-merge: don't compute bi_phys_segments from bi_vcnt for cloned bio
block: fix alignment_offset math that assumes io_min is a power-of-2
blk-mq: Make bt_clear_tag() easier to read
blk-mq: fix potential hang if rolling wakeup depth is too high
block: add bioset_create_nobvec()
block: use bio_clone_fast() in blk_rq_prep_clone()
block: misplaced rq_complete tracepoint
sd: Honor block layer integrity handling flags
block: Replace strnicmp with strncasecmp
block: Add T10 Protection Information functions
block: Don't merge requests if integrity flags differ
block: Integrity checksum flag
block: Relocate bio integrity flags
block: Add a disk flag to block integrity profile
block: Add prefix to block integrity profile flags
...
Diffstat (limited to 'Documentation/block')
-rw-r--r-- | Documentation/block/data-integrity.txt | 54 |
1 files changed, 5 insertions, 49 deletions
diff --git a/Documentation/block/data-integrity.txt b/Documentation/block/data-integrity.txt index 2d735b0ae383..f56ec97f0d14 100644 --- a/Documentation/block/data-integrity.txt +++ b/Documentation/block/data-integrity.txt @@ -129,11 +129,11 @@ interface for this is being worked on. 4.1 BIO The data integrity patches add a new field to struct bio when -CONFIG_BLK_DEV_INTEGRITY is enabled. bio->bi_integrity is a pointer -to a struct bip which contains the bio integrity payload. Essentially -a bip is a trimmed down struct bio which holds a bio_vec containing -the integrity metadata and the required housekeeping information (bvec -pool, vector count, etc.) +CONFIG_BLK_DEV_INTEGRITY is enabled. bio_integrity(bio) returns a +pointer to a struct bip which contains the bio integrity payload. +Essentially a bip is a trimmed down struct bio which holds a bio_vec +containing the integrity metadata and the required housekeeping +information (bvec pool, vector count, etc.) A kernel subsystem can enable data integrity protection on a bio by calling bio_integrity_alloc(bio). This will allocate and attach the @@ -192,16 +192,6 @@ will require extra work due to the application tag. supported by the block device. - int bdev_integrity_enabled(block_device, int rw); - - bdev_integrity_enabled() will return 1 if the block device - supports integrity metadata transfer for the data direction - specified in 'rw'. - - bdev_integrity_enabled() honors the write_generate and - read_verify flags in sysfs and will respond accordingly. - - int bio_integrity_prep(bio); To generate IMD for WRITE and to set up buffers for READ, the @@ -216,36 +206,6 @@ will require extra work due to the application tag. bio_integrity_enabled() returned 1. - int bio_integrity_tag_size(bio); - - If the filesystem wants to use the application tag space it will - first have to find out how much storage space is available. - Because tag space is generally limited (usually 2 bytes per - sector regardless of sector size), the integrity framework - supports interleaving the information between the sectors in an - I/O. - - Filesystems can call bio_integrity_tag_size(bio) to find out how - many bytes of storage are available for that particular bio. - - Another option is bdev_get_tag_size(block_device) which will - return the number of available bytes per hardware sector. - - - int bio_integrity_set_tag(bio, void *tag_buf, len); - - After a successful return from bio_integrity_prep(), - bio_integrity_set_tag() can be used to attach an opaque tag - buffer to a bio. Obviously this only makes sense if the I/O is - a WRITE. - - - int bio_integrity_get_tag(bio, void *tag_buf, len); - - Similarly, at READ I/O completion time the filesystem can - retrieve the tag buffer using bio_integrity_get_tag(). - - 5.3 PASSING EXISTING INTEGRITY METADATA Filesystems that either generate their own integrity metadata or @@ -298,8 +258,6 @@ will require extra work due to the application tag. .name = "STANDARDSBODY-TYPE-VARIANT-CSUM", .generate_fn = my_generate_fn, .verify_fn = my_verify_fn, - .get_tag_fn = my_get_tag_fn, - .set_tag_fn = my_set_tag_fn, .tuple_size = sizeof(struct my_tuple_size), .tag_size = <tag bytes per hw sector>, }; @@ -321,7 +279,5 @@ will require extra work due to the application tag. are available per hardware sector. For DIF this is either 2 or 0 depending on the value of the Control Mode Page ATO bit. - See 6.2 for a description of get_tag_fn and set_tag_fn. - ---------------------------------------------------------------------- 2007-12-24 Martin K. Petersen <martin.petersen@oracle.com> |