linux/Documentation/block
Christoph Hellwig 4246a0b63b block: add a bi_error field to struct bio
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 <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-07-29 08:55:15 -06:00
..
00-INDEX Documentation/: update 00-INDEX files 2014-02-10 16:01:40 -08:00
biodoc.txt block: add a bi_error field to struct bio 2015-07-29 08:55:15 -06:00
biovecs.txt block: Immutable bio vecs 2013-11-23 22:33:49 -08:00
capability.txt genhd: expose AN to user space 2007-05-23 20:14:11 -07:00
cfq-iosched.txt doc: Fix typo in doucmentations 2013-07-25 12:34:15 +02:00
cmdline-partition.txt block: change config option name for cmdline partition parsing 2013-09-30 14:31:02 -07:00
data-integrity.txt block: Remove integrity tagging functions 2014-09-27 09:14:50 -06:00
deadline-iosched.txt trivial: Miscellaneous documentation typo fixes 2009-06-12 18:01:47 +02:00
ioprio.txt Update Jens Axboe's email in Documentation/* 2007-10-16 09:59:55 +02:00
null_blk.txt Documentation: Fix null_blk parameter irq_mode to irqmode 2014-08-26 09:35:52 +02:00
queue-sysfs.txt block: make /sys/block/<dev>/queue/discard_max_bytes writeable 2015-07-17 08:41:53 -06:00
request.txt Update Jens Axboe's email in Documentation/* 2007-10-16 09:59:55 +02:00
stat.txt [PATCH] block/stat.txt 2006-01-08 20:14:01 -08:00
switching-sched.txt Documentation: drop as block elevator reference in switching-sched.txt 2011-11-04 12:01:48 -07:00
writeback_cache_control.txt block: update documentation for REQ_FLUSH / REQ_FUA 2010-09-10 12:35:37 +02:00