Skip to content

K
Kernel

openeuler / Kernel
12 个月 前同步成功

通知 5
Star 0
Fork 0
K
Kernel

体验新版 GitCode，发现更多精彩内容 >>

切换分支/标签
  1. 23 6月, 2006 2 次提交
    • R
      [PATCH] kernel-doc for mm/filemap.c · 485bb99b
      由 Randy Dunlap 提交于 
      mm/filemap.c:
- add lots of kernel-doc;
- fix some typos and kernel-doc errors;
- drop some blank lines between function close and EXPORT_SYMBOL();
Signed-off-by: NRandy Dunlap <rdunlap@xenotime.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      485bb99b
    • O
      [PATCH] writeback: fix range handling · 111ebb6e
      由 OGAWA Hirofumi 提交于 
      When a writeback_control's `start' and `end' fields are used to
indicate a one-byte-range starting at file offset zero, the required
values of .start=0,.end=0 mean that the ->writepages() implementation
has no way of telling that it is being asked to perform a range
request.  Because we're currently overloading (start == 0 && end == 0)
to mean "this is not a write-a-range request".

To make all this sane, the patch changes range of writeback_control.

So caller does: If it is calling ->writepages() to write pages, it
sets range (range_start/end or range_cyclic) always.

And if range_cyclic is true, ->writepages() thinks the range is
cyclic, otherwise it just uses range_start and range_end.

This patch does,

    - Add LLONG_MAX, LLONG_MIN, ULLONG_MAX to include/linux/kernel.h
      -1 is usually ok for range_end (type is long long). But, if someone did,

		range_end += val;		range_end is "val - 1"
		u64val = range_end >> bits;	u64val is "~(0ULL)"

      or something, they are wrong. So, this adds LLONG_MAX to avoid nasty
      things, and uses LLONG_MAX for range_end.

    - All callers of ->writepages() sets range_start/end or range_cyclic.

    - Fix updates of ->writeback_index. It seems already bit strange.
      If it starts at 0 and ended by check of nr_to_write, this last
      index may reduce chance to scan end of file.  So, this updates
      ->writeback_index only if range_cyclic is true or whole-file is
      scanned.
Signed-off-by: NOGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Nathan Scott <nathans@sgi.com>
Cc: Anton Altaparmakov <aia21@cantab.net>
Cc: Steven French <sfrench@us.ibm.com>
Cc: "Vladimir V. Saveliev" <vs@namesys.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      111ebb6e
  3. 27 4月, 2006 1 次提交
  5. 24 3月, 2006 3 次提交
    • A
      [PATCH] fadvise(): write commands · ebcf28e1
      由 Andrew Morton 提交于 
      Add two new linux-specific fadvise extensions():

LINUX_FADV_ASYNC_WRITE: start async writeout of any dirty pages between file
offsets `offset' and `offset+len'.  Any pages which are currently under
writeout are skipped, whether or not they are dirty.

LINUX_FADV_WRITE_WAIT: wait upon writeout of any dirty pages between file
offsets `offset' and `offset+len'.

By combining these two operations the application may do several things:

LINUX_FADV_ASYNC_WRITE: push some or all of the dirty pages at the disk.

LINUX_FADV_WRITE_WAIT, LINUX_FADV_ASYNC_WRITE: push all of the currently dirty
pages at the disk.

LINUX_FADV_WRITE_WAIT, LINUX_FADV_ASYNC_WRITE, LINUX_FADV_WRITE_WAIT: push all
of the currently dirty pages at the disk, wait until they have been written.

It should be noted that none of these operations write out the file's
metadata.  So unless the application is strictly performing overwrites of
already-instantiated disk blocks, there are no guarantees here that the data
will be available after a crash.

To complete this suite of operations I guess we should have a "sync file
metadata only" operation.  This gives applications access to all the building
blocks needed for all sorts of sync operations.  But sync-metadata doesn't fit
well with the fadvise() interface.  Probably it should be a new syscall:
sys_fmetadatasync().

The patch also diddles with the meaning of `endbyte' in sys_fadvise64_64().
It is made to represent that last affected byte in the file (ie: it is
inclusive).  Generally, all these byterange and pagerange functions are
inclusive so we can easily represent EOF with -1.

As Ulrich notes, these two functions are somewhat abusive of the fadvise()
concept, which appears to be "set the future policy for this fd".

But these commands are a perfect fit with the fadvise() impementation, and
several of the existing fadvise() commands are synchronous and don't affect
future policy either.   I think we can live with the slight incongruity.

Cc: Michael Kerrisk <mtk-manpages@gmx.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      ebcf28e1
    • A
      [PATCH] filemap_fdatawrite_range() api: clarify -end parameter · 469eb4d0
      由 Andrew Morton 提交于 
      I had trouble understanding working out whether filemap_fdatawrite_range()'s
`end' parameter describes the last-byte-to-be-written or the last-plus-one.
Clarify that in comments.
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      469eb4d0
    • P
      [PATCH] cpuset memory spread page cache implementation and hooks · 44110fe3
      由 Paul Jackson 提交于 
      Change the page cache allocation calls to support cpuset memory spreading.

See the previous patch, cpuset_mem_spread, for an explanation of cpuset memory
spreading.

On systems without cpusets configured in the kernel, this is no change.

On systems with cpusets configured in the kernel, but the "memory_spread"
cpuset option not enabled for the current tasks cpuset, this adds a call to a
cpuset routine and failed bit test of the processor state flag PF_SPREAD_PAGE.

On tasks in cpusets with "memory_spread" enabled, this adds a call to a cpuset
routine that computes which of the tasks mems_allowed nodes should be
preferred for this allocation.

If memory spreading applies to a particular allocation, then any other NUMA
mempolicy does not apply.
Signed-off-by: NPaul Jackson <pj@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      44110fe3
  7. 22 3月, 2006 1 次提交
  9. 19 1月, 2006 1 次提交
  11. 12 1月, 2006 1 次提交
  13. 11 1月, 2006 1 次提交
  15. 10 1月, 2006 1 次提交
  17. 09 1月, 2006 2 次提交
  19. 07 1月, 2006 1 次提交
  21. 04 1月, 2006 1 次提交
    • Z
      [PATCH] add AOP_TRUNCATED_PAGE, prepend AOP_ to WRITEPAGE_ACTIVATE · 994fc28c
      由 Zach Brown 提交于 
      readpage(), prepare_write(), and commit_write() callers are updated to
understand the special return code AOP_TRUNCATED_PAGE in the style of
writepage() and WRITEPAGE_ACTIVATE.  AOP_TRUNCATED_PAGE tells the caller that
the callee has unlocked the page and that the operation should be tried again
with a new page.  OCFS2 uses this to detect and work around a lock inversion in
its aop methods.  There should be no change in behaviour for methods that don't
return AOP_TRUNCATED_PAGE.

WRITEPAGE_ACTIVATE is also prepended with AOP_ for consistency and they are
made enums so that kerneldoc can be used to document their semantics.
Signed-off-by: NZach Brown <zach.brown@oracle.com>
      994fc28c
  23. 15 11月, 2005 1 次提交
  25. 31 10月, 2005 1 次提交
    • T
      [PATCH] fs: error case fix in __generic_file_aio_read · 39e88ca2
      由 Tejun Heo 提交于 
      When __generic_file_aio_read() hits an error during reading, it reports the
error iff nothing has successfully been read yet.  This is condition - when
an error occurs, if nothing has been read/written, report the error code;
otherwise, report the amount of bytes successfully transferred upto that
point.

This corner case can be exposed by performing readv(2) with the following
iov.

 iov[0] = len0 @ ptr0
 iov[1] = len1 @ NULL (or any other invalid pointer)
 iov[2] = len2 @ ptr2

When file size is enough, performing above readv(2) results in

 len0 bytes from file_pos @ ptr0
 len2 bytes from file_pos + len0 @ ptr2

And the return value is len0 + len2.  Test program is attached to this
mail.

This patch makes __generic_file_aio_read()'s error handling identical to
other functions.

#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/uio.h>
#include <errno.h>
#include <string.h>

int main(int argc, char **argv)
{
	const char *path;
	struct stat stbuf;
	size_t len0, len1;
	void *buf0, *buf1;
	struct iovec iov[3];
	int fd, i;
	ssize_t ret;

	if (argc < 2) {
		fprintf(stderr, "Usage: testreadv path (better be a "
			"small text file)\n");
		return 1;
	}
	path = argv[1];

	if (stat(path, &stbuf) < 0) {
		perror("stat");
		return 1;
	}

	len0 = stbuf.st_size / 2;
	len1 = stbuf.st_size - len0;

	if (!len0 || !len1) {
		fprintf(stderr, "Dude, file is too small\n");
		return 1;
	}

	if ((fd = open(path, O_RDONLY)) < 0) {
		perror("open");
		return 1;
	}

	if (!(buf0 = malloc(len0)) || !(buf1 = malloc(len1))) {
		perror("malloc");
		return 1;
	}

	memset(buf0, 0, len0);
	memset(buf1, 0, len1);

	iov[0].iov_base = buf0;
	iov[0].iov_len = len0;
	iov[1].iov_base = NULL;
	iov[1].iov_len = len1;
	iov[2].iov_base = buf1;
	iov[2].iov_len = len1;

	printf("vector ");
	for (i = 0; i < 3; i++)
		printf("%p:%zu ", iov[i].iov_base, iov[i].iov_len);
	printf("\n");

	ret = readv(fd, iov, 3);
	if (ret < 0)
		perror("readv");

	printf("readv returned %zd\nbuf0 = [%s]\nbuf1 = [%s]\n",
	       ret, (char *)buf0, (char *)buf1);

	return 0;
}
Signed-off-by: NTejun Heo <htejun@gmail.com>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      39e88ca2
  27. 30 10月, 2005 4 次提交
    • N
      [PATCH] mm/filemap.c:filemap_populate(): move export. · b1459461
      由 Nikita Danilov 提交于 
      move EXPORT_SYMBOL(filemap_populate) to the proper place: just after
function itself: it's easy to miss that function is exported otherwise.
Signed-off-by: NNikita Danilov <nikita@clusterfs.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      b1459461
    • H
      [PATCH] mm: update comments to pte lock · b8072f09
      由 Hugh Dickins 提交于 
      Updated several references to page_table_lock in common code comments.
Signed-off-by: NHugh Dickins <hugh@veritas.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      b8072f09
    • H
      [PATCH] mm: split page table lock · 4c21e2f2
      由 Hugh Dickins 提交于 
      Christoph Lameter demonstrated very poor scalability on the SGI 512-way, with
a many-threaded application which concurrently initializes different parts of
a large anonymous area.

This patch corrects that, by using a separate spinlock per page table page, to
guard the page table entries in that page, instead of using the mm's single
page_table_lock.  (But even then, page_table_lock is still used to guard page
table allocation, and anon_vma allocation.)

In this implementation, the spinlock is tucked inside the struct page of the
page table page: with a BUILD_BUG_ON in case it overflows - which it would in
the case of 32-bit PA-RISC with spinlock debugging enabled.

Splitting the lock is not quite for free: another cacheline access.  Ideally,
I suppose we would use split ptlock only for multi-threaded processes on
multi-cpu machines; but deciding that dynamically would have its own costs.
So for now enable it by config, at some number of cpus - since the Kconfig
language doesn't support inequalities, let preprocessor compare that with
NR_CPUS.  But I don't think it's worth being user-configurable: for good
testing of both split and unsplit configs, split now at 4 cpus, and perhaps
change that to 8 later.

There is a benefit even for singly threaded processes: kswapd can be attacking
one part of the mm while another part is busy faulting.
Signed-off-by: NHugh Dickins <hugh@veritas.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      4c21e2f2
    • H
      [PATCH] mm: page fault handlers tidyup · 65500d23
      由 Hugh Dickins 提交于 
      Impose a little more consistency on the page fault handlers do_wp_page,
do_swap_page, do_anonymous_page, do_no_page, do_file_page: why not pass their
arguments in the same order, called the same names?

break_cow is all very well, but what it did was inlined elsewhere: easier to
compare if it's brought back into do_wp_page.

do_file_page's fallback to do_no_page dates from a time when we were testing
pte_file by using it wherever possible: currently it's peculiar to nonlinear
vmas, so just check that.  BUG_ON if not?  Better not, it's probably page
table corruption, so just show the pte: hmm, there's a pte_ERROR macro, let's
use that for do_wp_page's invalid pfn too.

Hah!  Someone in the ppc64 world noticed pte_ERROR was unused so removed it:
restored (and say "pud" not "pmd" in its pud_ERROR).
Signed-off-by: NHugh Dickins <hugh@veritas.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      65500d23
  29. 28 10月, 2005 1 次提交
  31. 11 9月, 2005 1 次提交
  33. 05 9月, 2005 2 次提交
    • P
      [PATCH] shmem_populate: avoid an useless check, and some comments · d44ed4f8
      由 Paolo 'Blaisorblade' Giarrusso 提交于 
      Either shmem_getpage returns a failure, or it found a page, or it was told
it couldn't do any I/O.  So it's useless to check nonblock in the else
branch.  We could add a BUG() there but I preferred to comment the
offending function.

This was taken out from one Ingo Molnar's old patch I'm resurrecting.
Signed-off-by: NPaolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      d44ed4f8
    • H
      [PATCH] swap: swap_lock replace list+device · 5d337b91
      由 Hugh Dickins 提交于 
      The idea of a swap_device_lock per device, and a swap_list_lock over them all,
is appealing; but in practice almost every holder of swap_device_lock must
already hold swap_list_lock, which defeats the purpose of the split.

The only exceptions have been swap_duplicate, valid_swaphandles and an
untrodden path in try_to_unuse (plus a few places added in this series).
valid_swaphandles doesn't show up high in profiles, but swap_duplicate does
demand attention.  However, with the hold time in get_swap_pages so much
reduced, I've not yet found a load and set of swap device priorities to show
even swap_duplicate benefitting from the split.  Certainly the split is mere
overhead in the common case of a single swap device.

So, replace swap_list_lock and swap_device_lock by spinlock_t swap_lock
(generally we seem to prefer an _ in the name, and not hide in a macro).

If someone can show a regression in swap_duplicate, then probably we should
add a hashlock for the swap_map entries alone (shorts being anatomic), so as
to help the case of the single swap device too.
Signed-off-by: NHugh Dickins <hugh@veritas.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      5d337b91
  35. 26 6月, 2005 2 次提交
  37. 24 6月, 2005 2 次提交
  39. 07 6月, 2005 1 次提交
  41. 22 5月, 2005 1 次提交
    • S
      [PATCH] fix for __generic_file_aio_read() to return 0 on EOF · b5c44c21
      由 Suparna Bhattacharya 提交于 
      I came across the following problem while running ltp-aiodio testcases from
ltp-full-20050405 on linux-2.6.12-rc3-mm3.  I tried running the tests with
EXT3 as well as JFS filesystems.

One or two fsx-linux testcases were hung after some time.  These testcases
were hanging at wait_for_all_aios().

Debugging shows that there were some iocbs which were not getting completed
eventhough the last retry for those returned -EIOCBQUEUED.  Also all such
pending iocbs represented READ operation.

Further debugging revealed that all such iocbs hit EOF in the DIO layer.
To be more precise, the "pos" from which they were trying to read was
greater than the "size" of the file.  So the generic_file_direct_IO
returned 0.

This happens rarely as there is already a check in
__generic_file_aio_read(), for whether "pos" < "size" before calling direct
IO routine.

>size = i_size_read(inode);
>if (pos < size) {
>	  retval = generic_file_direct_IO(READ, iocb,
>                               iov, pos, nr_segs);

But for READ, we are taking the inode->i_sem only in the DIO layer.  So it
is possible that some other process can change the size of the file before
we take the i_sem.  In such a case ( when "pos" > "size"), the
__generic_file_aio_read() would return -EIOCBQUEUED even though there were
no I/O requests submitted by the DIO layer.  This would cause the AIO layer
to expect aio_complete() for THE iocb, which doesnot happen.  And thus the
test hangs forever, waiting for an I/O completion, where there are no
requests submitted at all.

The following patch makes __generic_file_aio_read() return 0 (instead of
returning -EIOCBQUEUED), on getting 0 from generic_file_direct_IO(), so
that the AIO layer does the aio_complete().

Testing:

I have tested the patch on a SMP machine(with 2 Pentium 4 (HT)) running
linux-2.6.12-rc3-mm3.  I ran the ltp-aiodio testcases and none of the
fsx-linux tests hung.  Also the aio-stress tests ran without any problem.
Signed-off-by: NSuzuki K P <suzuki@in.ibm.com>
Signed-off-by: NSuparna Bhattacharya <suparna@in.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      b5c44c21
  43. 06 5月, 2005 1 次提交
  45. 01 5月, 2005 4 次提交
  47. 17 4月, 2005 2 次提交
    • J
      [PATCH] filemap_getpage can block when MAP_NONBLOCK specified · d3457342
      由 Jeff Moyer 提交于 
      We will return NULL from filemap_getpage when a page does not exist in the
page cache and MAP_NONBLOCK is specified, here:

	page = find_get_page(mapping, pgoff);
	if (!page) {
		if (nonblock)
			return NULL;
		goto no_cached_page;
	}

But we forget to do so when the page in the cache is not uptodate.  The
following could result in a blocking call:

	/*
	 * Ok, found a page in the page cache, now we need to check
	 * that it's up-to-date.
	 */
	if (!PageUptodate(page))
		goto page_not_uptodate;
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      d3457342
    • L
      Linux-2.6.12-rc2 · 1da177e4
      由 Linus Torvalds 提交于 
      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!
      1da177e4