Commit Graph

37 Commits

Author SHA1 Message Date
Alexey Dobriyan 405f55712d headers: smp_lock.h redux
* Remove smp_lock.h from files which don't need it (including some headers!)
* Add smp_lock.h to files which do need it
* Make smp_lock.h include conditional in hardirq.h
  It's needed only for one kernel_locked() usage which is under CONFIG_PREEMPT

  This will make hardirq.h inclusion cheaper for every PREEMPT=n config
  (which includes allmodconfig/allyesconfig, BTW)

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-12 12:22:34 -07:00
Linus Torvalds e1f5b94fd0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6: (143 commits)
  USB: xhci depends on PCI.
  USB: xhci: Add Makefile, MAINTAINERS, and Kconfig entries.
  USB: xhci: Respect critical sections.
  USB: xHCI: Fix interrupt moderation.
  USB: xhci: Remove packed attribute from structures.
  usb; xhci: Fix TRB offset calculations.
  USB: xhci: replace if-elseif-else with switch-case
  USB: xhci: Make xhci-mem.c include linux/dmapool.h
  USB: xhci: drop spinlock in xhci_urb_enqueue() error path.
  USB: Change names of SuperSpeed ep companion descriptor structs.
  USB: xhci: Avoid compiler reordering in Link TRB giveback.
  USB: xhci: Clean up xhci_irq() function.
  USB: xhci: Avoid global namespace pollution.
  USB: xhci: Fix Link TRB handoff bit twiddling.
  USB: xhci: Fix register write order.
  USB: xhci: fix some compiler warnings in xhci.h
  USB: xhci: fix lots of compiler warnings.
  USB: xhci: use xhci_handle_event instead of handle_event
  USB: xhci: URB cancellation support.
  USB: xhci: Scatter gather list support for bulk transfers.
  ...
2009-06-16 13:06:10 -07:00
Linus Torvalds 23059a0df5 Merge git://git.kernel.org/pub/scm/linux/kernel/git/hirofumi/fatfs-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/hirofumi/fatfs-2.6:
  fat: split fat_generic_ioctl
  FAT: add 'errors' mount option
2009-06-16 11:29:44 -07:00
Alan Stern 74675a5850 NLS: update handling of Unicode
This patch (as1239) updates the kernel's treatment of Unicode.  The
character-set conversion routines are well behind the current state of
the Unicode specification: They don't recognize the existence of code
points beyond plane 0 or of surrogate pairs in the UTF-16 encoding.

The old wchar_t 16-bit type is retained because it's still used in
lots of places.  This shouldn't cause any new problems; if a
conversion now results in an invalid 16-bit code then before it must
have yielded an undefined code.

Difficult-to-read names like "utf_mbstowcs" are replaced with more
transparent names like "utf8s_to_utf16s" and the ordering of the
parameters is rationalized (buffer lengths come immediate after the
pointers they refer to, and the inputs precede the outputs).
Fortunately the low-level conversion routines are used in only a few
places; the interfaces to the higher-level uni2char and char2uni
methods have been left unchanged.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-06-15 21:44:43 -07:00
Al Viro b522412aea Sanitize ->fsync() for FAT
* mark directory data blocks as assoc. metadata
* add new inode to deal with FAT, mark FAT blocks as assoc. metadata of that
* now ->fsync() is trivial both for files and directories

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11 21:36:12 -04:00
Denis Karpov 85c7859190 FAT: add 'errors' mount option
On severe errors FAT remounts itself in read-only mode. Allow to
specify FAT fs desired behavior through 'errors' mount option:
panic, continue or remount read-only.

`mount -t [fat|vfat] -o errors=[panic,remount-ro,continue] \
	<bdev> <mount point>`

This is analog to ext2 fs 'errors' mount option.

Signed-off-by: Denis Karpov <ext-denis.2.karpov@nokia.com>
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
2009-06-04 02:34:51 +09:00
OGAWA Hirofumi 985eafcc54 fat: fix duplicate addition of ->llseek handler
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
2008-11-12 08:51:22 +09:00
OGAWA Hirofumi c3302931db fat: i_blocks warning fix
blkcnt_t type depends on CONFIG_LSF. Use unsigned long long always for
printk().  But lazy to type it, so add "llu" and use it.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-11-06 15:41:22 -08:00
OGAWA Hirofumi 2bdf67eb16 fat: mmu_private race fix
mmu_private is 64bits value, hence it's not atomic to update.

So, the access rule for mmu_private is we must hold ->i_mutex.  But,
fat_get_block() path doesn't follow the rule on non-allocation path.

This fixes by using i_size instead if non-allocation path.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-11-06 15:41:21 -08:00
Darren Jenkins 52e9d9f4b3 fat: cleanup fat_parse_long() error handling
Coverity CID 2332 & 2333 RESOURCE_LEAK

In fat_search_long() if fat_parse_long() returns a -ve value we return
without first freeing unicode.  This patch free's them on this error path.

The above was false positive on current tree, but this change is more
clean, so apply as cleanup.

[hirofumi@mail.parknet.co.jp: fix coding style]
Signed-off-by: Darren Jenkins <darrenrjenkins@gmail.com>
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-11-06 15:41:20 -08:00
OGAWA Hirofumi 53472bc8f8 fat: use generic_file_llseek() for directory
Since fat_dir_ioctl() was already fixed (i.e. called under ->i_mutex),
and __fat_readdir() doesn't take BKL anymore. So, BKL for ->llseek()
is pointless, and we have to use generic_file_llseek().

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-11-06 15:41:20 -08:00
OGAWA Hirofumi 7decd1cb03 fat: Fix and cleanup timestamp conversion
This cleans date_dos2unix()/fat_date_unix2dos() up. New code should be
much more readable.

And this fixes those old functions. Those doesn't handle 2100
correctly. 2100 isn't leap year, but old one handles it as leap year.
Also, with this, centi sec is handled and is fixed.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-11-06 15:41:20 -08:00
OGAWA Hirofumi 9e975dae29 fat: split include/msdos_fs.h
This splits __KERNEL__ stuff in include/msdos_fs.h into fs/fat/fat.h.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-11-06 15:41:20 -08:00
Christoph Hellwig 3222a3e55f [PATCH] fix ->llseek for more directories
With this patch all directory fops instances that have a readdir
that doesn't take the BKL are switched to generic_file_llseek.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2008-10-23 05:13:21 -04:00
Joe Peterson b271e067c8 fatfs: add UTC timestamp option
Provide a new mount option ("tz=UTC") for DOS (vfat/msdos) filesystems,
allowing timestamps to be in coordinated universal time (UTC) rather than
local time in applications where doing this is advantageous.

In particular, portable devices that use fat/vfat (such as digital
cameras) can benefit from using UTC in their internal clocks, thus
avoiding daylight saving time errors and general time ambiguity issues.
The user of the device does not have to worry about changing the time when
moving from place or when daylight saving changes.

The new mount option, when set, disables the counter-adjustment that Linux
currently makes to FAT timestamp info in anticipation of the normal
userspace time zone correction.  When used in this new mode, all daylight
saving time and time zone handling is done in userspace as is normal for
many other filesystems (like ext3).  The default mode, which remains
unchanged, is still appropriate when mounting volumes written in Windows
(because of its use of local time).

I originally based this patch on one submitted last year by Paul Collins,
but I updated it to work with current source and changed variable/option
naming.  Ogawa Hirofumi (who maintains these filesystems) and I discussed
this patch at length on lkml, and he suggested using the option name in
the attached version of the patch.  Barry Bouwsma pointed out a good
addition to the patch as well.

Signed-off-by: Joe Peterson <joe@skyrush.com>
Signed-off-by: Paul Collins <paul@ondioline.org>
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Barry Bouwsma <free_beer_for_all@yahoo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:34 -07:00
OGAWA Hirofumi dcd8c53f13 fat: small optimization to __fat_readdir()
This removes unnecessary parsing for directory entries.

If short_only, we don't need to parse longname.  And if !both and it found
the longname, we don't need shortname.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:34 -07:00
OGAWA Hirofumi 98a1516004 fat: use same logic in fat_search_long() and __fat_readdir()
This uses uses stack for shortname, and uses __getname() for longname in
fat_search_long() and __fat_readdir().  By this, it removes unneeded
__getname() for shortname.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:34 -07:00
OGAWA Hirofumi d688611674 fat: cleanup fs/fat/dir.c
This is no logic changes, just cleans fs/fat/dir.c up.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:34 -07:00
Adrian Bunk 531f710f8e fat/dir.c: switch to struct __fat_dirent
struct __fat_dirent is what was formerly the kernel struct dirent (that
was different from the userspace struct dirent).

Converting all fat users to struct __fat_dirent will allow us to get rid
of the conflicting struct dirent definition.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:34 -07:00
Linus Torvalds 8f5934278d Replace BKL with superblock lock in fat/msdos/vfat
This replaces the use of the BKL in the FAT family of filesystems with the
existing superblock lock instead.

The code already appears to do mostly proper locking with its own private
spinlocks (and mutexes), but while the BKL could possibly have been
dropped entirely, converting it to use the superblock lock (which is just
a regular mutex) is the conservative thing to do.

As a per-filesystem mutex, it not only won't have any of the possible
latency issues related to the BKL, but the lock is obviously private to
the particular filesystem instance and will thus not cause problems for
entirely unrelated users like the BKL can.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2008-06-20 14:05:54 -06:00
OGAWA Hirofumi c7a6c4edc7 fat: use __getname()
__getname() is faster than __get_free_page(). Use it.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 08:58:47 -07:00
Keith Mok f22032ba8d vfat: bug fix for vfat cannot handle filename with 255
This patch fix the problem that the buffer allocated for convert of unicode to
utf8 in fat/dir.c is too small.

And cannot handle filename with 255 asian characters when mounted with utf8
options.

Also it fix the filename length limitation checking in vfat/namei.c that the
filename length should be checked against the number of converted unicode
characters.

Not the length before NLS/UTF8 converted.

Signed-off-by: Keith Mok <ek9852@gmail.com>
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 08:58:47 -07:00
OGAWA Hirofumi 9aacd59934 fat: gcc 4.3 warning fix
This patch fixes the following warnings.

fs/fat/dir.c: In function 'fat_parse_long':
include/linux/msdos_fs.h:294: warning: array subscript is above array bounds
include/linux/msdos_fs.h:295: warning: array subscript is above array bounds
include/linux/msdos_fs.h:295: warning: array subscript is above array bounds

The ->name is defined as "name[8], ext[3]", but fat_checksum() uses
those as name[11]. There is no actual problem, but it's not a good manner.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 09:05:42 -07:00
OGAWA Hirofumi c483bab099 fat: fix VFAT compat ioctls on 64-bit systems
If you compile and run the below test case in an msdos or vfat directory on
an x86-64 system with -m32 you'll get garbage in the kernel_dirent struct
followed by a SIGSEGV.

The patch fixes this.

Reported and initial fix by Bart Oldeman

#include <sys/types.h>
#include <sys/ioctl.h>
#include <dirent.h>
#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
struct kernel_dirent {
         long            d_ino;
         long		d_off;
         unsigned short  d_reclen;
         char            d_name[256]; /* We must not include limits.h! */
};
#define VFAT_IOCTL_READDIR_BOTH  _IOR('r', 1, struct kernel_dirent [2])
#define VFAT_IOCTL_READDIR_SHORT  _IOR('r', 2, struct kernel_dirent [2])

int main(void)
{
         int fd = open(".", O_RDONLY);
         struct kernel_dirent de[2];

         while (1) {
                 int i = ioctl(fd, VFAT_IOCTL_READDIR_BOTH, (long)de);
                 if (i == -1) break;
                 if (de[0].d_reclen == 0) break;
                 printf("SFN: reclen=%2d off=%d ino=%d, %-12s",
 		       de[0].d_reclen, de[0].d_off, de[0].d_ino, de[0].d_name);
 		if (de[1].d_reclen)
 		  printf("\tLFN: reclen=%2d off=%d ino=%d, %s",
 		    de[1].d_reclen, de[1].d_off, de[1].d_ino, de[1].d_name);
 		printf("\n");
         }
         return 0;
}

Signed-off-by: Bart Oldeman <bartoldeman@users.sourceforge.net>
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 11:15:14 -07:00
Josef "Jeff" Sipek dba3230609 [PATCH] fat: change uses of f_{dentry,vfsmnt} to use f_path
Change all the uses of f_{dentry,vfsmnt} to f_path.{dentry,mnt} in the fat
filesystem.

Signed-off-by: Josef "Jeff" Sipek <jsipek@cs.sunysb.edu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08 08:28:41 -08:00
David Howells afefdbb28a [PATCH] VFS: Make filldir_t and struct kstat deal in 64-bit inode numbers
These patches make the kernel pass 64-bit inode numbers internally when
communicating to userspace, even on a 32-bit system.  They are required
because some filesystems have intrinsic 64-bit inode numbers: NFS3+ and XFS
for example.  The 64-bit inode numbers are then propagated to userspace
automatically where the arch supports it.

Problems have been seen with userspace (eg: ld.so) using the 64-bit inode
number returned by stat64() or getdents64() to differentiate files, and
failing because the 64-bit inode number space was compressed to 32-bits, and
so overlaps occur.

This patch:

Make filldir_t take a 64-bit inode number and struct kstat carry a 64-bit
inode number so that 64-bit inode numbers can be passed back to userspace.

The stat functions then returns the full 64-bit inode number where
available and where possible.  If it is not possible to represent the inode
number supplied by the filesystem in the field provided by userspace, then
error EOVERFLOW will be issued.

Similarly, the getdents/readdir functions now pass the full 64-bit inode
number to userspace where possible, returning EOVERFLOW instead when a
directory entry is encountered that can't be properly represented.

Note that this means that some inodes will not be stat'able on a 32-bit
system with old libraries where they were before - but it does mean that
there will be no ambiguity over what a 32-bit inode number refers to.

Note similarly that directory scans may be cut short with an error on a
32-bit system with old libraries where the scan would work before for the
same reasons.

It is judged unlikely that this situation will occur because modern glibc
uses 64-bit capable versions of stat and getdents class functions
exclusively, and that older systems are unlikely to encounter
unrepresentable inode numbers anyway.

[akpm: alpha build fix]
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-03 08:03:40 -07:00
David Howells 188f83dfe0 [PATCH] BLOCK: Move the msdos device ioctl compat stuff to the msdos driver [try #6]
Move the msdos device ioctl compat stuff from fs/compat_ioctl.c to the msdos
driver so that the msdos header file doesn't need to be included.

Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2006-09-30 20:52:30 +02:00
Arjan van de Ven 4b6f5d20b0 [PATCH] Make most file operations structs in fs/ const
This is a conversion to make the various file_operations structs in fs/
const.  Basically a regexp job, with a few manual fixups

The goal is both to increase correctness (harder to accidentally write to
shared datastructures) and reducing the false sharing of cachelines with
things that get dirty in .data (while .rodata is nicely read only and thus
cache clean)

Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 09:16:06 -08:00
Alexey Dobriyan 4de151d8cd It's UTF-8
Fix some comments to "UTF-8".

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-03-22 00:13:35 +01:00
Jes Sorensen 1b1dcc1b57 [PATCH] mutex subsystem, semaphore to mutex: VFS, ->i_sem
This patch converts the inode semaphore to a mutex. I have tested it on
XFS and compiled as much as one can consider on an ia64. Anyway your
luck with it might be different.

Modified-by: Ingo Molnar <mingo@elte.hu>

(finished the conversion)

Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2006-01-09 15:59:24 -08:00
OGAWA Hirofumi e5174baaea [PATCH] fat: support ->direct_IO()
This patch add to support of ->direct_IO() for mostly read.

The user of this seems to want to use for streaming read.  So, current direct
I/O has limitation, it can only overwrite.  (For write operation, mainly we
need to handle the hole etc..)

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:13:46 -08:00
OGAWA Hirofumi 7c709d00d6 [PATCH] fat: s/EXPORT_SYMBOL/EXPORT_SYMBOL_GPL/
All EXPORT_SYMBOL of fatfs is only for vfat/msdos. _GPL would be proper.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:13:46 -08:00
OGAWA Hirofumi 83b7c996dc [PATCH] fat: use sb_find_get_block() instead of sb_getblk()
We don't need to allocate buffer for checking the buffer is uptodate.  This
use sb_find_get_block() instead, and if it returns NULL it's not uptodate.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:13:46 -08:00
Pekka Enberg ad2c1604da [PATCH] fat: Remove duplicate directory scanning code
This patch removes duplicate directory scanning code from fs/fat/dir.c.  The
two functions that share identical code are fat_readdirx() and
fat_search_long().  This patch also renames fat_readdirx to __fat_readdir().

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 17:37:32 -08:00
OGAWA Hirofumi 451cbaa1c3 [PATCH] fat: cleanup and optimization of checksum
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 17:37:32 -08:00
Karsten Wiese f3ef6f63e5 [PATCH] Speedup FAT filesystem directory reads
OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>

This speeds up directory reads for large FAT partitions, if the buffercache
has to be filled from the drive. Following values were taken from:

        $ time find path_to_freshly_mounted_fat > /dev/null

on an otherwise idle system.

FAT with 16KB Clusters on IDE attached drive:   Factor  2
FAT with 32KB Clusters on USB2 attached drive:  Factor 10 (!)
Its less than 1/10 slower, if the buffercache is uptodate.

The patch introduces the new function fat_dir_readahead().

fat_dir_readahead() calls sb_breadahead() to readahead a whole cluster,
if the requested sector is the first one in a cluster.
It is usefull to do this, because on FAT directories occupy whole
clusters, with the exception of FAT12/FAT16 root dirs.

Readahead is only done, if the cluster's first sector is not uptodate
to avoid overhead, when the buffer cache is already uptodate.
Note that under memory pressure, the maximal byte count wasted
(read: has to be red from disk twice) is 1 cluster's size.  Thats 64KB.

fat_dir_readahead() is called from fat__get_entry().

There is also an unrelated cleanup at one spot:

        if (bh)
                brelse(bh);

is replaced with:

        brelse(bh);

brelse() can handle NULL pointer arguments by itself.

Signed-off-by: Karsten Wiese <annabellesgarden@yahoo.de>
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:26 -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