Commit Graph

10 Commits

Author SHA1 Message Date
Mike Snitzer
21136f89d7 dm mpath: remove repeat_count support from multipath core
Preparation for making __multipath_map() avoid taking the m->lock
spinlock -- in favor of using RCU locking.

repeat_count was primarily for bio-based DM multipath's benefit.  There
is really no need for it anymore now that DM multipath is request-based.
As such, repeat_count > 1 is no longer honored and a warning is
displayed if the user attempts to use a value > 1.  This is a temporary
change for the round-robin path-selector (as a later commit will restore
its support for repeat_count > 1).

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2016-02-22 22:34:40 -05:00
Mikulas Patocka
31998ef193 dm: reject trailing characters in sccanf input
Device mapper uses sscanf to convert arguments to numbers. The problem is that
the way we use it ignores additional unmatched characters in the scanned string.

For example, this `if (sscanf(string, "%d", &number) == 1)' will match a number,
but also it will match number with some garbage appended, like "123abc".

As a result, device mapper accepts garbage after some numbers. For example
the command `dmsetup create vg1-new --table "0 16384 linear 254:1bla 34816bla"'
will pass without an error.

This patch fixes all sscanf uses in device mapper. It appends "%c" with
a pointer to a dummy character variable to every sscanf statement.

The construct `if (sscanf(string, "%d%c", &number, &dummy) == 1)' succeeds
only if string is a null-terminated number (optionally preceded by some
whitespace characters). If there is some character appended after the number,
sscanf matches "%c", writes the character to the dummy variable and returns 2.
We check the return value for 1 and consequently reject numbers with some
garbage appended.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-03-28 18:41:26 +01:00
Paul Gortmaker
056075c764 md: Add module.h to all files using it implicitly
A pending cleanup will mean that module.h won't be implicitly
everywhere anymore.  Make sure the modular drivers in md dir
are actually calling out for <module.h> explicitly in advance.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:31:18 -04:00
Kiyoshi Ueda
02ab823fd1 dm mpath: add start_io and nr_bytes to path selectors
This patch makes two additions to the dm path selector interface for
dynamic load balancers:
  o a new hook, start_io()
  o a new parameter 'nr_bytes' to select_path()/start_io()/end_io()
    to pass the size of the I/O

start_io() is called when a target driver actually submits I/O
to the selected path.
Path selectors can use it to start accounting of the I/O.
(e.g. counting the number of in-flight I/Os.)
The start_io hook is based on the patch posted by Stefan Bader:
https://www.redhat.com/archives/dm-devel/2005-October/msg00050.html

nr_bytes, the size of the I/O, is so path selectors can take the
size of the I/O into account when deciding which path to use.
dm-service-time uses it to estimate service time, for example.
(Added the nr_bytes member to dm_mpath_io instead of using existing
 details.bi_size, since request-based dm patch deletes it.)

Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-06-22 10:12:27 +01:00
Mikulas Patocka
586e80e6ee dm: remove dm header from targets
Change #include "dm.h" to #include <linux/device-mapper.h> in all targets.
Targets should not need direct access to internal DM structures.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2008-10-21 17:44:59 +01:00
Alasdair G Kergon
0cd3312434 dm: remove duplicate module name from error msgs
Remove explicit module name from messages as the macro now includes it
automatically.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-12 15:01:08 -07:00
Josef "Jeff" Sipek
c922d5f7f5 [PATCH] struct path: rename DM's struct path
Rename DM's struct path to struct dm_path to prevent name collision between it
and struct path from fs/namei.c.

Signed-off-by: Josef "Jeff" Sipek <jsipek@cs.sunysb.edu>
Acked-by: Alasdair G Kergon <agk@redhat.com>
Cc: <reiserfs-dev@namesys.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08 08:28:40 -08:00
Jonathan E Brassow
5d55fdf949 [PATCH] dm: multipath: fix rr_add_path order
When adding paths to the round-robin path selector, their order gets inverted,
which is not desirable.

Fix by replacing list_add() with list_add_tail().

Signed-off-by: Jonathan E Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: <dm-devel@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-08 18:29:23 -08:00
Alasdair G Kergon
72d9486169 [PATCH] dm: improve error message consistency
Tidy device-mapper error messages to include context information
automatically.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:36 -07:00
Linus Torvalds
1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00