linux.git/fs/ext3, branch v2.6.27

[PATCH] fix races and leaks in vfs_quota_on() users

2008-08-01T15:25:25+00:00

* new helper: vfs_quota_on_path(); equivalent of vfs_quota_on() sans the
  pathname resolution.
* callers of vfs_quota_on() that do their own pathname resolution and
  checks based on it are switched to vfs_quota_on_path(); that way we
  avoid the races.
* reiserfs leaked dentry/vfsmount references on several failure exits.

Signed-off-by: Al Viro

vfs: pagecache usage optimization for pagesize!=blocksize

2008-07-28T23:30:21+00:00

When we read some part of a file through pagecache, if there is a
pagecache of corresponding index but this page is not uptodate, read IO
is issued and this page will be uptodate.

I think this is good for pagesize == blocksize environment but there is
room for improvement on pagesize != blocksize environment.  Because in
this case a page can have multiple buffers and even if a page is not
uptodate, some buffers can be uptodate.

So I suggest that when all buffers which correspond to a part of a file
that we want to read are uptodate, use this pagecache and copy data from
this pagecache to user buffer even if a page is not uptodate.  This can
reduce read IO and improve system throughput.

I wrote a benchmark program and got result number with this program.

This benchmark do:

  1: mount and open a test file.

  2: create a 512MB file.

  3: close a file and umount.

  4: mount and again open a test file.

  5: pwrite randomly 300000 times on a test file.  offset is aligned
     by IO size(1024bytes).

  6: measure time of preading randomly 100000 times on a test file.

The result was:
	2.6.26
        330 sec

	2.6.26-patched
        226 sec

Arch:i386
Filesystem:ext3
Blocksize:1024 bytes
Memory: 1GB

On ext3/4, a file is written through buffer/block.  So random read/write
mixed workloads or random read after random write workloads are optimized
with this patch under pagesize != blocksize environment.  This test result
showed this.

The benchmark program is as follows:

#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 

#define LEN 1024
#define LOOP 1024*512 /* 512MB */

main(void)
{
	unsigned long i, offset, filesize;
	int fd;
	char buf[LEN];
	time_t t1, t2;

	if (mount("/dev/sda1", "/root/test1/", "ext3", 0, 0) < 0) {
		perror("cannot mount\n");
		exit(1);
	}
	memset(buf, 0, LEN);
	fd = open("/root/test1/testfile", O_CREAT|O_RDWR|O_TRUNC);
	if (fd < 0) {
		perror("cannot open file\n");
		exit(1);
	}
	for (i = 0; i < LOOP; i++)
		write(fd, buf, LEN);
	close(fd);
	if (umount("/root/test1/") < 0) {
		perror("cannot umount\n");
		exit(1);
	}
	if (mount("/dev/sda1", "/root/test1/", "ext3", 0, 0) < 0) {
		perror("cannot mount\n");
		exit(1);
	}
	fd = open("/root/test1/testfile", O_RDWR);
	if (fd < 0) {
		perror("cannot open file\n");
		exit(1);
	}

	filesize = LEN * LOOP;
	for (i = 0; i < 300000; i++){
		offset = (random() % filesize) & (~(LEN - 1));
		pwrite(fd, buf, LEN, offset);
	}
	printf("start test\n");
	time(&t1);
	for (i = 0; i < 100000; i++){
		offset = (random() % filesize) & (~(LEN - 1));
		pread(fd, buf, LEN, offset);
	}
	time(&t2);
	printf("%ld sec\n", t2-t1);
	close(fd);
	if (umount("/root/test1/") < 0) {
		perror("cannot umount\n");
		exit(1);
	}
}

Signed-off-by: Hisashi Hifumi 
Cc: Nick Piggin 
Cc: Christoph Hellwig 
Cc: Jan Kara 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] sanitize ->permission() prototype

2008-07-27T00:53:14+00:00

* kill nameidata * argument; map the 3 bits in ->flags anybody cares
  about to new MAY_... ones and pass with the mask.
* kill redundant gfs2_iop_permission()
* sanitize ecryptfs_permission()
* fix remaining places where ->permission() instances might barf on new
  MAY_... found in mask.

The obvious next target in that direction is permission(9)

folded fix for nfs_permission() breakage from Miklos Szeredi 

Signed-off-by: Al Viro

SL*B: drop kmem cache argument from constructor

2008-07-26T19:00:07+00:00

Kmem cache passed to constructor is only needed for constructors that are
themselves multiplexeres.  Nobody uses this "feature", nor does anybody uses
passed kmem cache in non-trivial way, so pass only pointer to object.

Non-trivial places are:
	arch/powerpc/mm/init_64.c
	arch/powerpc/mm/hugetlbpage.c

This is flag day, yes.

Signed-off-by: Alexey Dobriyan 
Acked-by: Pekka Enberg 
Acked-by: Christoph Lameter 
Cc: Jon Tollefson 
Cc: Nick Piggin 
Cc: Matt Mackall 
[akpm@linux-foundation.org: fix arch/powerpc/mm/hugetlbpage.c]
[akpm@linux-foundation.org: fix mm/slab.c]
[akpm@linux-foundation.org: fix ubifs]
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

ext3: validate directory entry data before use

2008-07-25T17:53:33+00:00

ext3_dx_find_entry uses ext3_next_entry without verifying that the entry
is valid.  If its rec_len == 0 this causes an infinite loop.  Refactor the
loop to check the validity of entries before checking whether they match
and moving onto the next one.

There are other uses of ext3_next_entry in this file which also look
problematic.  They should be reviewed and fixed if/when we have a
test-case that triggers them.

This patch fixes the first case (image hdb.25.softlockup.gz) reported in
http://bugzilla.kernel.org/show_bug.cgi?id=10882.

Signed-off-by: Duane Griffin 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

ext3: kill 2 useless magic numbers

2008-07-25T17:53:32+00:00

dx_root_limit() will never return 20, and I can't figure out what 20
stands for.  This function has never changed since htree directory
indexing was merged.

Similar for dx_node_limit() and the magic 22.

Signed-off-by: Li Zefan 
Acked-by: Andreas Dilger 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

ext3: handle deleting corrupted indirect blocks

2008-07-25T17:53:32+00:00

While freeing indirect blocks we attach a journal head to the parent
buffer head, free the blocks, then journal the parent.  If the indirect
block list is corrupted and points to the parent the journal head will be
detached when the block is cleared, causing an OOPS.

Check for that explicitly and handle it gracefully.

This patch fixes the third case (image hdb.20000057.nullderef.gz)
reported in http://bugzilla.kernel.org/show_bug.cgi?id=10882.

Immediately above the change, in the ext3_free_data function, we call
ext3_clear_blocks to clear the indirect blocks in this parent block.  If
one of those blocks happens to actually be the parent block it will clear
b_private / BH_JBD.

I did the check at the end rather than earlier as it seemed more elegant.
I don't think there should be much practical difference, although it is
possible the FS may not be quite so badly corrupted if we did it the other
way (and didn't clear the block at all).  To be honest, I'm not convinced
there aren't other similar failure modes lurking in this code, although I
couldn't find any with a quick review.

[akpm@linux-foundation.org: fix printk warning]
Signed-off-by: Duane Griffin 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

ext3: don't read inode block if the buffer has a write error

2008-07-25T17:53:32+00:00

A transient I/O error can corrupt inode data.  Here is the scenario:

(1) update inode_A at the block_B
(2) pdflush writes out new inode_A to the filesystem, but it results
    in write I/O error, at this point, BH_Uptodate flag of the buffer
    for block_B is cleared and BH_Write_EIO is set
(3) create new inode_C which located at block_B, and
    __ext3_get_inode_loc() tries to read on-disk block_B because the
    buffer is not uptodate
(4) if it can read on-disk block_B successfully, inode_A is
    overwritten by old data

This patch makes __ext3_get_inode_loc() not read the inode block if the
buffer has BH_Write_EIO flag.  In this case, the buffer should have the
latest information, so setting the uptodate flag to the buffer (this
avoids WARN_ON_ONCE() in mark_buffer_dirty().)

According to this change, we would need to test BH_Write_EIO flag for the
error checking.  Currently nobody checks write I/O errors on metadata
buffers, but it will be done in other patches I'm working on.

Signed-off-by: Hidehiro Kawai 
Cc: sugita 
Cc: Satoshi OSHIMA 
Cc: Nick Piggin 
Cc: Jan Kara 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

ext3: handle corrupted orphan list at mount

2008-07-25T17:53:32+00:00

If the orphan node list includes valid, untruncatable nodes with nlink > 0
the ext3_orphan_cleanup loop which attempts to delete them will not do so,
causing it to loop forever. Fix by checking for such nodes in the
ext3_orphan_get function.

This patch fixes the second case (image hdb.20000009.softlockup.gz)
reported in http://bugzilla.kernel.org/show_bug.cgi?id=10882.

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: printk warning fix]
Signed-off-by: Duane Griffin 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

ext3: remove double definitions of xattr macros

2008-07-25T17:53:32+00:00

remove the definitions of macros:
XATTR_TRUSTED_PREFIX
XATTR_USER_PREFIX
since they are defined in linux/xattr.h

Signed-off-by: Shen Feng 
Signed-off-by: Mingming Cao 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds