kernel.git/fs/gfs2/file.c, branch linux-3.3.y

Merge git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-3.0-nmw

2012-01-08T21:07:54Z

* git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-3.0-nmw: GFS2: local functions should be static GFS2: We only need one ACL getting function GFS2: Fix multi-block allocation GFS2: decouple quota allocations from block allocations GFS2: split function rgblk_search GFS2: Fix up "off by one" in the previous patch GFS2: move toward a generic multi-block allocator GFS2: O_(D)SYNC support for fallocate GFS2: remove vestigial al_alloced GFS2: combine gfs2_alloc_block and gfs2_alloc_di GFS2: Add non-try locks back to get_local_rgrp GFS2: f_ra is always valid in dir readahead function GFS2: Fix very unlikley memory leak in ACL xattr code GFS2: More automated code analysis fixes GFS2: Add readahead to sequential directory traversal GFS2: Fix up REQ flags

vfs: mnt_drop_write_file()

2012-01-04T03:52:40Z

new helper (wrapper around mnt_drop_write()) to be used in pair with mnt_want_write_file(). Signed-off-by: Al Viro

switch a bunch of places to mnt_want_write_file()

2012-01-04T03:52:35Z

it's both faster (in case when file has been opened for write) and cleaner. Signed-off-by: Al Viro

GFS2: decouple quota allocations from block allocations

2011-11-22T10:25:21Z

This patch separates the code pertaining to allocations into two parts: quota-related information and block reservations. This patch also moves all the block reservation structure allocations to function gfs2_inplace_reserve to simplify the code, and moves the frees to function gfs2_inplace_release. Signed-off-by: Bob Peterson Signed-off-by: Steven Whitehouse

GFS2: O_(D)SYNC support for fallocate

2011-11-21T10:01:25Z

Add sync of metadata after fallocate for O_SYNC files to ensure that we meet expectations for everything being on disk in this case. Unfortunately, the offset and len parameters are modified during the course of the fallocate function, so I've had to add a couple of new variables to call generic_write_sync() at the end. I know that potentially this will sync data as well within the range, but I think that is a fairly harmless side-effect overall, since we would not normally expect there to be any dirty data within the range in question. Signed-off-by: Steven Whitehouse Cc: Christoph Hellwig Cc: Benjamin Marzinski

GFS2: More automated code analysis fixes

2011-11-08T14:04:20Z

A potentially uninitialised variable, some unreachable code, and the main part of this, fixing the error path in the unlink function. Signed-off-by: Steven Whitehouse

GFS2: Add readahead to sequential directory traversal

2011-11-08T09:52:12Z

This patch adds read-ahead capability to GFS2's directory hash table management. It greatly improves performance for some directory operations. For example: In one of my file systems that has 1000 directories, each of which has 1000 files, time to execute a recursive ls (time ls -fR /mnt/gfs2 > /dev/null) was reduced from 2m2.814s on a stock kernel to 0m45.938s. Signed-off-by: Bob Peterson Signed-off-by: Steven Whitehouse

Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/hch/vfs-queue

2011-10-28T17:49:34Z

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/hch/vfs-queue: (21 commits) leases: fix write-open/read-lease race nfs: drop unnecessary locking in llseek ext4: replace cut'n'pasted llseek code with generic_file_llseek_size vfs: add generic_file_llseek_size vfs: do (nearly) lockless generic_file_llseek direct-io: merge direct_io_walker into __blockdev_direct_IO direct-io: inline the complete submission path direct-io: separate map_bh from dio direct-io: use a slab cache for struct dio direct-io: rearrange fields in dio/dio_submit to avoid holes direct-io: fix a wrong comment direct-io: separate fields only used in the submission path from struct dio vfs: fix spinning prevention in prune_icache_sb vfs: add a comment to inode_permission() vfs: pass all mask flags check_acl and posix_acl_permission vfs: add hex format for MAY_* flag values vfs: indicate that the permission functions take all the MAY_* flags compat: sync compat_stats with statfs. vfs: add "device" tag to /proc/self/mountstats cleanup: vfs: small comment fix for block_invalidatepage ... Fix up trivial conflict in fs/gfs2/file.c (llseek changes)

vfs: do (nearly) lockless generic_file_llseek

2011-10-28T12:58:58Z

The i_mutex lock use of generic _file_llseek hurts. Independent processes accessing the same file synchronize over a single lock, even though they have no need for synchronization at all. Under high utilization this can cause llseek to scale very poorly on larger systems. This patch does some rethinking of the llseek locking model: First the 64bit f_pos is not necessarily atomic without locks on 32bit systems. This can already cause races with read() today. This was discussed on linux-kernel in the past and deemed acceptable. The patch does not change that. Let's look at the different seek variants: SEEK_SET: Doesn't really need any locking. If there's a race one writer wins, the other loses. For 32bit the non atomic update races against read() stay the same. Without a lock they can also happen against write() now. The read() race was deemed acceptable in past discussions, and I think if it's ok for read it's ok for write too. => Don't need a lock. SEEK_END: This behaves like SEEK_SET plus it reads the maximum size too. Reading the maximum size would have the 32bit atomic problem. But luckily we already have a way to read the maximum size without locking (i_size_read), so we can just use that instead. Without i_mutex there is no synchronization with write() anymore, however since the write() update is atomic on 64bit it just behaves like another racy SEEK_SET. On non atomic 32bit it's the same as SEEK_SET. => Don't need a lock, but need to use i_size_read() SEEK_CUR: This has a read-modify-write race window on the same file. One could argue that any application doing unsynchronized seeks on the same file is already broken. But for the sake of not adding a regression here I'm using the file->f_lock to synchronize this. Using this lock is much better than the inode mutex because it doesn't synchronize between processes. => So still need a lock, but can use a f_lock. This patch implements this new scheme in generic_file_llseek. I dropped generic_file_llseek_unlocked and changed all callers. Signed-off-by: Andi Kleen Signed-off-by: Christoph Hellwig

GFS2: rewrite fallocate code to write blocks directly

2011-10-21T11:39:49Z

GFS2's fallocate code currently goes through the page cache. Since it's only writing to the end of the file or to holes in it, it doesn't need to, and it was causing issues on low memory environments. This patch pulls in some of Steve's block allocation work, and uses it to simply allocate the blocks for the file, and zero them out at allocation time. It provides a slight performance increase, and it dramatically simplifies the code. Signed-off-by: Benjamin Marzinski Signed-off-by: Steven Whitehouse