kernel.git/fs/fcntl.c, branch linux-2.6.19.y

[PATCH] file: Add locking to f_getown

2006-10-02T14:57:15Z

This has been needed for a long time, but now with the advent of a reference counted struct pid there are real consequences for getting this wrong. Someone I think it was Oleg Nesterov pointed out that this construct was missing locking, when I introduced struct pid. After taking time to review the locking construct already present I figured out which lock needs to be taken. The other paths that access f_owner.pid take either the f_owner read or the write lock. Signed-off-by: Eric W. Biederman Cc: Oleg Nesterov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] file: modify struct fown_struct to use a struct pid

2006-10-02T14:57:14Z

File handles can be requested to send sigio and sigurg to processes. By tracking the destination processes using struct pid instead of pid_t we make the interface safe from all potential pid wrap around problems. Signed-off-by: Eric W. Biederman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

BUG_ON() Conversion in fs/fcntl.c

2006-04-02T11:37:19Z

this changes if() BUG(); constructs to BUG_ON() which is cleaner and can better optimized away Signed-off-by: Eric Sesterhenn Signed-off-by: Adrian Bunk

[PATCH] Use __read_mostly on some hot fs variables

2006-03-26T16:56:56Z

I discovered on oprofile hunting on a SMP platform that dentry lookups were slowed down because d_hash_mask, d_hash_shift and dentry_hashtable were in a cache line that contained inodes_stat. So each time inodes_stats is changed by a cpu, other cpus have to refill their cache line. This patch moves some variables to the __read_mostly section, in order to avoid false sharing. RCU dentry lookups can go full speed. Signed-off-by: Eric Dumazet Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] Shrinks sizeof(files_struct) and better layout

2006-03-23T15:38:09Z

1) Reduce the size of (struct fdtable) to exactly 64 bytes on 32bits platforms, lowering kmalloc() allocated space by 50%. 2) Reduce the size of (files_struct), using a special 32 bits (or 64bits) embedded_fd_set, instead of a 1024 bits fd_set for the close_on_exec_init and open_fds_init fields. This save some ram (248 bytes per task) as most tasks dont open more than 32 files. D-Cache footprint for such tasks is also reduced to the minimum. 3) Reduce size of allocated fdset. Currently two full pages are allocated, that is 32768 bits on x86 for example, and way too much. The minimum is now L1_CACHE_BYTES. UP and SMP should benefit from this patch, because most tasks will touch only one cache line when open()/close() stdin/stdout/stderr (0/1/2), (next_fd, close_on_exec_init, open_fds_init, fd_array[0 .. 2] being in the same cache line) Signed-off-by: Eric Dumazet Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] fcntl F_SETFL and read-only IS_APPEND files

2006-02-03T16:32:07Z

There is code in setfl() which attempts to preserve the O_APPEND flag on IS_APPEND files... however IS_APPEND files could also be opened O_RDONLY and in that case setfl() should not require O_APPEND... coreutils 5.93 tail -f attempts to set O_NONBLOCK even on regular files... unfortunately if you try this on an append-only log file the result is this: fcntl64(3, F_GETFL) = 0x8000 (flags O_RDONLY|O_LARGEFILE) fcntl64(3, F_SETFL, O_RDONLY|O_NONBLOCK|O_LARGEFILE) = -1 EPERM (Operation not permitted) I offer up the patch below as one way of fixing the problem... i've tested it fixes the problem with tail -f but haven't really tested beyond that. (I also reported the coreutils bug upstream... it shouldn't fail imho... ) Signed-off-by: dean gaudet Cc: Al Viro Acked-by: Christoph Hellwig Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] Unlinline a bunch of other functions

2006-01-15T02:27:06Z

Remove the "inline" keyword from a bunch of big functions in the kernel with the goal of shrinking it by 30kb to 40kb Signed-off-by: Arjan van de Ven Signed-off-by: Ingo Molnar Acked-by: Jeff Garzik Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] capable/capability.h (fs/)

2006-01-12T02:42:13Z

fs: Use where capable() is used. Signed-off-by: Randy Dunlap Acked-by: Tim Schmielau Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] sigio: cleanup, don't take tasklist twice

2006-01-09T04:13:57Z

The only user of send_sigio_to_task() already holds tasklist_lock, so it is better not to send the signal via send_group_sig_info() (which takes tasklist recursively) but use group_send_sig_info(). The same change in send_sigurg()->send_sigurg_to_task(). Signed-off-by: Oleg Nesterov Cc: "Paul E. McKenney" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] files: lock-free fd look-up

2005-09-09T20:57:55Z

With the use of RCU in files structure, the look-up of files using fds can now be lock-free. The lookup is protected by rcu_read_lock()/rcu_read_unlock(). This patch changes the readers to use lock-free lookup. Signed-off-by: Maneesh Soni Signed-off-by: Ravikiran Thirumalai Signed-off-by: Dipankar Sarma Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds