linux-stable.git/drivers/md/bcache/sysfs.c, branch linux-3.16.y

bcache: Correct return value for sysfs attach errors

2017-11-26T13:50:34+00:00

commit 77fa100f27475d08a569b9d51c17722130f089e7 upstream.

If you encounter any errors in bch_cached_dev_attach it will return
a negative error code.  The variable 'v' which stores the result is
unsigned, thus user space sees a very large value returned for bytes
written which can cause incorrect user space behavior.  Utilize 1
signed variable to use throughout the function to preserve error return
capability.

Signed-off-by: Tony Asleson 
Acked-by: Coly Li 
Signed-off-by: Jens Axboe 
Signed-off-by: Ben Hutchings

bcache: remove nested function usage

2014-03-18T19:39:28+00:00

Uninlined nested functions can cause crashes when using ftrace, as they don't
follow the normal calling convention and confuse the ftrace function graph
tracer as it examines the stack.

Also, nested functions are supported as a gcc extension, but may fail on other
compilers (e.g. llvm).

Signed-off-by: John Sheu

bcache: Rework btree cache reserve handling

2014-03-18T19:23:35+00:00

This changes the bucket allocation reserves to use _real_ reserves - separate
freelists - instead of watermarks, which if nothing else makes the current code
saner to reason about and is going to be important in the future when we add
support for multiple btrees.

It also adds btree_check_reserve(), which checks (and locks) the reserves for
both bucket allocation and memory allocation for btree nodes; the old code just
kinda sorta assumed that since (e.g. for btree node splits) it had the root
locked and that meant no other threads could try to make use of the same
reserve; this technically should have been ok for memory allocation (we should
always have a reserve for memory allocation (the btree node cache is used as a
reserve and we preallocate it)), but multiple btrees will mean that locking the
root won't be sufficient anymore, and for the bucket allocation reserve it was
technically possible for the old code to deadlock.

Signed-off-by: Kent Overstreet

bcache: Improve priority_stats

2014-03-18T19:22:35+00:00

Break down data into clean data/dirty data/metadata.

Signed-off-by: Kent Overstreet

bcache: Minor fixes from kbuild robot

2014-01-29T21:06:41+00:00

Signed-off-by: Kent Overstreet

bcache: Convert btree_iter to struct btree_keys

2014-01-08T21:05:13+00:00

More work to disentangle bset.c from struct btree

Signed-off-by: Kent Overstreet

bcache: Refactor bset_tree sysfs stats

2014-01-08T21:05:13+00:00

We're in the process of turning bset.c into library code, so none of the code in
that file should know about struct cache_set or struct btree - so, move the
btree traversal part of the stats code to sysfs.c.

Signed-off-by: Kent Overstreet

bcache: Add struct btree_keys

2014-01-08T21:05:13+00:00

Soon, bset.c won't need to depend on struct btree.

Signed-off-by: Kent Overstreet

bcache: Add struct bset_sort_state

2014-01-08T21:05:12+00:00

More disentangling bset.c from the rest of the bcache code - soon, the
sorting routines won't have any dependencies on any outside structs.

Signed-off-by: Kent Overstreet

bcache: Rework allocator reserves

2014-01-08T21:05:09+00:00

We need a reserve for allocating buckets for new btree nodes - and now that
we've got multiple btrees, it really needs to be per btree.

This reworks the reserves so we've got separate freelists for each reserve
instead of watermarks, which seems to make things a bit cleaner, and it adds
some code so that btree_split() can make sure the reserve is available before it
starts.

Signed-off-by: Kent Overstreet