| Age | Commit message (Collapse) | Author |
|---|
|
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
|
|
|
|
The "strictlimit" feature was introduced to enforce per-bdi dirty limits
for FUSE which sets bdi max_ratio to 1% by default:
http://article.gmane.org/gmane.linux.kernel.mm/105809
However the feature can be useful for other relatively slow or untrusted
BDIs like USB flash drives and DVD+RW. The patch adds a knob to enable
the feature:
echo 1 > /sys/class/bdi/X:Y/strictlimit
Being enabled, the feature enforces bdi max_ratio limit even if global
(10%) dirty limit is not reached. Of course, the effect is not visible
until /sys/class/bdi/X:Y/max_ratio is decreased to some reasonable value.
Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com>
Cc: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: "Artem S. Tashkinov" <t.artem@lycos.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Jan Kara <jack@suse.cz>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Currently, memsetting and kfreeing the device is bad behaviour. The
device will have a reference count of 1 and hence can cause trouble
because it has kfree'd. Proper way to handle a failed device_register is
to call put_device right after it fails.
Signed-off-by: Levente Kurusa <levex@linux.com>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
remap_file_pages(2) was invented to be able efficiently map parts of huge
file into limited 32-bit virtual address space such as in database
workloads.
Nonlinear mappings are pain to support and it seems there's no legitimate
use-cases nowadays since 64-bit systems are widely available.
Let's drop it and get rid of all these special-cased code.
The patch replaces the syscall with emulation which creates new VMA on
each remap_file_pages(), unless they it can be merged with an adjacent
one.
I didn't find *any* real code that uses remap_file_pages(2) to test
emulation impact on. I've checked Debian code search and source of all
packages in ALT Linux. No real users: libc wrappers, mentions in strace,
gdb, valgrind and this kind of stuff.
There are few basic tests in LTP for the syscall. They work just fine
with emulation.
To test performance impact, I've written small test case which demonstrate
pretty much worst case scenario: map 4G shmfs file, write to begin of
every page pgoff of the page, remap pages in reverse order, read every
page.
The test creates 1 million of VMAs if emulation is in use, so I had to set
vm.max_map_count to 1100000 to avoid -ENOMEM.
Before: 23.3 ( +- 4.31% ) seconds
After: 43.9 ( +- 0.85% ) seconds
Slowdown: 1.88x
I believe we can live with that.
Test case:
#define _GNU_SOURCE
#include <assert.h>
#include <stdlib.h>
#include <stdio.h>
#include <sys/mman.h>
#define MB (1024UL * 1024)
#define SIZE (4096 * MB)
int main(int argc, char **argv)
{
unsigned long *p;
long i, pass;
for (pass = 0; pass < 10; pass++) {
p = mmap(NULL, SIZE, PROT_READ|PROT_WRITE,
MAP_SHARED | MAP_ANONYMOUS, -1, 0);
if (p == MAP_FAILED) {
perror("mmap");
return -1;
}
for (i = 0; i < SIZE / 4096; i++)
p[i * 4096 / sizeof(*p)] = i;
for (i = 0; i < SIZE / 4096; i++) {
if (remap_file_pages(p + i * 4096 / sizeof(*p), 4096,
0, (SIZE - 4096 * (i + 1)) >> 12, 0)) {
perror("remap_file_pages");
return -1;
}
}
for (i = SIZE / 4096 - 1; i >= 0; i--)
assert(p[i * 4096 / sizeof(*p)] == SIZE / 4096 - i - 1);
munmap(p, SIZE);
}
return 0;
}
[akpm@linux-foundation.org: fix spello]
[sasha.levin@oracle.com: initialize populate before usage]
[sasha.levin@oracle.com: grab file ref to prevent race while mmaping]
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Dave Jones <davej@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Armin Rigo <arigo@tunes.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Update the limitation for fat fallocate.
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Make the fibmap call the return the proper physical block number for any
offset request in the fallocated range.
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Skip new cluster allocation after checking i_disksize in _fat_get_block.
because the blocks are already allocated in fallocated region.
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Implement preallocation via the fallocate syscall on VFAT partitions.
This patch is based on an earlier patch of the same name which had some
issues detailed below and did not get accepted. Refer
https://lkml.org/lkml/2007/12/22/130.
a) The preallocated space was not persistent when the
FALLOC_FL_KEEP_SIZE flag was set. It will deallocate cluster at evict
time.
b) There was no need to zero out the clusters when the flag was set
Instead of doing an expanding truncate, just allocate clusters and add
them to the fat chain. This reduces preallocation time.
Compatibility with windows:
There are no issues when FALLOC_FL_KEEP_SIZE is not set because it just
does an expanding truncate. Thus reading from the preallocated area on
windows returns null until data is written to it.
When a file with preallocated area using the FALLOC_FL_KEEP_SIZE was
written to on windows, the windows driver freed-up the preallocated
clusters and allocated new clusters for the new data. The freed up
clusters gets reflected in the free space available for the partition
which can be seen from the Volume properties.
The windows chkdsk tool also does not report any errors on a disk
containing files with preallocated space.
And there is also no issue using linux fat fsck. because discard
preallocated clusters at repair time.
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
This patchset provides support for doing fallocate operation on FAT
filesystem.
This patch (of 5):
Add i_disksize to represent uninitialized allocated size. And mmu_private
represent initialized allocated size. i_disksize - is always kept cluster
size aligned mmu_private - is normally block size aligned
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Unbreak i386 allmodconfig.
This is a hack - please fix properly ;)
Cc: Fabian Vogt <fabian@ritter-vogt.de>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Conflicts:
arch/arm64/mm/dma-mapping.c
drivers/base/dma-contiguous.c
drivers/clk/Kconfig
fs/proc/task_mmu.c
mm/slab.c
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Conflicts:
fs/nfs/client.c
|
|
|
|
|
|
Conflicts:
drivers/vhost/net.c
|
|
Conflicts:
drivers/scsi/qla2xxx/qla_target.c
|
|
|
|
|
|
Conflicts:
drivers/leds/leds-gpio.c
|
|
|
|
|
|
Conflicts:
arch/s390/include/asm/cputime.h
arch/s390/kernel/irq.c
arch/s390/kernel/processor.c
arch/s390/kernel/vtime.c
kernel/irq_work.c
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Conflicts:
arch/arm64/kernel/ptrace.c
arch/x86/kernel/entry_64.S
arch/x86/kernel/ptrace.c
|
|
|
|
|
|
|
|
|
|
Conflicts:
drivers/power/reset/Kconfig
drivers/power/reset/Makefile
|
|
|
|
|
|
|
|
|
|
Conflicts:
block/blk-core.c
|
|
|
|
|
|
|
