diff options
Diffstat (limited to 'Documentation/block')
| -rw-r--r-- | Documentation/block/biodoc.txt | 10 | ||||
| -rw-r--r-- | Documentation/block/data-integrity.txt | 54 | ||||
| -rw-r--r-- | Documentation/block/null_blk.txt | 4 | ||||
| -rw-r--r-- | Documentation/block/queue-sysfs.txt | 6 |
4 files changed, 15 insertions, 59 deletions
diff --git a/Documentation/block/biodoc.txt b/Documentation/block/biodoc.txt index 2101e718670d..5aabc08de811 100644 --- a/Documentation/block/biodoc.txt +++ b/Documentation/block/biodoc.txt @@ -827,10 +827,6 @@ but in the event of any barrier requests in the tag queue we need to ensure that requests are restarted in the order they were queue. This may happen if the driver needs to use blk_queue_invalidate_tags(). -Tagging also defines a new request flag, REQ_QUEUED. This is set whenever -a request is currently tagged. You should not use this flag directly, -blk_rq_tagged(rq) is the portable way to do so. - 3.3 I/O Submission The routine submit_bio() is used to submit a single io. Higher level i/o @@ -946,7 +942,11 @@ elevator_allow_merge_fn called whenever the block layer determines request safely. The io scheduler may still want to stop a merge at this point if it results in some sort of conflict internally, - this hook allows it to do that. + this hook allows it to do that. Note however + that two *requests* can still be merged at later + time. Currently the io scheduler has no way to + prevent that. It can only learn about the fact + from elevator_merge_req_fn callback. elevator_dispatch_fn* fills the dispatch queue with ready requests. I/O schedulers are free to postpone requests by 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> diff --git a/Documentation/block/null_blk.txt b/Documentation/block/null_blk.txt index b2830b435895..2f6c6ff7161d 100644 --- a/Documentation/block/null_blk.txt +++ b/Documentation/block/null_blk.txt @@ -42,7 +42,7 @@ nr_devices=[Number of devices]: Default: 2 Number of block devices instantiated. They are instantiated as /dev/nullb0, etc. -irq_mode=[0-2]: Default: 1-Soft-irq +irqmode=[0-2]: Default: 1-Soft-irq The completion mode used for completing IOs to the block-layer. 0: None. @@ -53,7 +53,7 @@ irq_mode=[0-2]: Default: 1-Soft-irq completion. completion_nsec=[ns]: Default: 10.000ns - Combined with irq_mode=2 (timer). The time each completion event must wait. + Combined with irqmode=2 (timer). The time each completion event must wait. submit_queues=[0..nr_cpus]: The number of submission queues attached to the device driver. If unset, it diff --git a/Documentation/block/queue-sysfs.txt b/Documentation/block/queue-sysfs.txt index 7d2d046c265f..3a29f8914df9 100644 --- a/Documentation/block/queue-sysfs.txt +++ b/Documentation/block/queue-sysfs.txt @@ -11,7 +11,7 @@ read-write. add_random (RW) ---------------- -This file allows to trun off the disk entropy contribution. Default +This file allows to turn off the disk entropy contribution. Default value of this file is '1'(on). discard_granularity (RO) @@ -72,7 +72,7 @@ Maximum segment size of the device. minimum_io_size (RO) -------------------- -This is the smallest preferred io size reported by the device. +This is the smallest preferred IO size reported by the device. nomerges (RW) ------------- @@ -98,7 +98,7 @@ regulated by nr_requests. optimal_io_size (RO) -------------------- -This is the optimal io size reported by the device. +This is the optimal IO size reported by the device. physical_block_size (RO) ------------------------ |