linux/include
Neil Brown da6e1a32fb [PATCH] md: avoid possible BUG_ON in md bitmap handling
md/bitmap tracks how many active write requests are pending on blocks
associated with each bit in the bitmap, so that it knows when it can clear
the bit (when count hits zero).

The counter has 14 bits of space, so if there are ever more than 16383, we
cannot cope.

Currently the code just calles BUG_ON as "all" drivers have request queue
limits much smaller than this.

However is seems that some don't.  Apparently some multipath configurations
can allow more than 16383 concurrent write requests.

So, in this unlikely situation, instead of calling BUG_ON we now wait
for the count to drop down a bit.  This requires a new wait_queue_head,
some waiting code, and a wakeup call.

Tested by limiting the counter to 20 instead of 16383 (writes go a lot slower
in that case...).

Signed-off-by: Neil Brown <neilb@suse.de>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-09 09:25:47 -08:00
..
acpi Pull sysfs into test branch 2007-02-03 01:14:35 -05:00
asm-alpha [PATCH] kill eth_io_copy_and_sum() 2007-02-09 09:14:07 -08:00
asm-arm [PATCH] kill eth_io_copy_and_sum() 2007-02-09 09:14:07 -08:00
asm-arm26 [PATCH] Optimize D-cache alias handling on fork 2006-12-13 09:27:08 -08:00
asm-avr32 [AVR32] ssize_t should be long, not int 2007-02-09 15:01:59 +01:00
asm-cris [PATCH] kill eth_io_copy_and_sum() 2007-02-09 09:14:07 -08:00
asm-frv [PATCH] fix frv headers_check 2007-02-01 16:17:05 -08:00
asm-generic Fix Maple PATA IRQ assignment. 2007-01-26 17:27:40 -05:00
asm-h8300 [PATCH] Optimize D-cache alias handling on fork 2006-12-13 09:27:08 -08:00
asm-i386 [PATCH] kill eth_io_copy_and_sum() 2007-02-09 09:14:07 -08:00
asm-ia64 Merge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/pci-2.6 2007-02-07 19:23:44 -08:00
asm-m32r [PATCH] Optimize D-cache alias handling on fork 2006-12-13 09:27:08 -08:00
asm-m68k [PATCH] m68k: uaccess.h needs sched.h 2007-01-30 08:26:45 -08:00
asm-m68knommu [PATCH] Optimize D-cache alias handling on fork 2006-12-13 09:27:08 -08:00
asm-mips Merge branch 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-tc 2007-02-09 09:22:36 -08:00
asm-parisc [PATCH] kill eth_io_copy_and_sum() 2007-02-09 09:14:07 -08:00
asm-powerpc [POWERPC] Add mpc52xx/lite5200 PCI support 2007-02-08 15:29:22 +11:00
asm-ppc [PATCH] kill eth_io_copy_and_sum() 2007-02-09 09:14:07 -08:00
asm-s390 [S390] Mark kernel text section read-only. 2007-02-05 21:18:41 +01:00
asm-sh [PATCH] Optimize D-cache alias handling on fork 2006-12-13 09:27:08 -08:00
asm-sh64 [PATCH] Optimize D-cache alias handling on fork 2006-12-13 09:27:08 -08:00
asm-sparc [SPARC32]: Fix over-optimization by GCC near ip_fast_csum. 2007-02-01 20:24:35 -08:00
asm-sparc64 [SPARC64]: Fix of_iounmap() region release. 2006-12-31 14:06:05 -08:00
asm-um [PATCH] uml-i386: fix build breakage with CONFIG_HIGHMEM 2007-02-01 16:17:06 -08:00
asm-v850 [PATCH] Optimize D-cache alias handling on fork 2006-12-13 09:27:08 -08:00
asm-x86_64 [PATCH] kill eth_io_copy_and_sum() 2007-02-09 09:14:07 -08:00
asm-xtensa [PATCH] FD_ZERO build fix 2007-01-11 18:18:22 -08:00
crypto [CRYPTO] api: Allow multiple frontends per backend 2007-02-07 09:21:01 +11:00
keys
linux [PATCH] md: avoid possible BUG_ON in md bitmap handling 2007-02-09 09:25:47 -08:00
math-emu
media V4L/DVB (5001): Add two required headers on kernel 2.6.20-rc1 2006-12-27 14:20:46 -02:00
mtd
net [NET]: change layout of ehash table 2007-02-08 14:16:46 -08:00
pcmcia Driver core: convert pcmcia code to use struct device 2007-02-07 10:37:11 -08:00
rdma IB: Make sure struct ib_user_mad.data is aligned 2007-02-04 14:11:56 -08:00
rxrpc
scsi [PATCH] iscsi endianness annotations 2007-02-09 09:14:07 -08:00
sound [PATCH] Fix breakage with CONFIG_SYSFS_DEPRECATED 2007-02-09 16:25:48 +01:00
video [PATCH] sstfb: add sysfs interface 2006-12-13 09:05:55 -08:00
Kbuild