ALSA: asihpi - Fix uninitialized variable

[safe/jmp/linux-2.6] / Documentation / filesystems / Locking

diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking
index 18b9d0c..96d4293 100644 (file)
--- a/Documentation/filesystems/Locking
+++ b/Documentation/filesystems/Locking
@@ -178,7 +178,7 @@ prototypes:
 locking rules:
        All except set_page_dirty may block
 
-                       BKL     PageLocked(page)        i_sem
+                       BKL     PageLocked(page)        i_mutex
 writepage:             no      yes, unlocks (see below)
 readpage:              no      yes, unlocks
 sync_page:             no      maybe
@@ -380,7 +380,7 @@ prototypes:
        int (*open) (struct inode *, struct file *);
        int (*flush) (struct file *);
        int (*release) (struct inode *, struct file *);
-       int (*fsync) (struct file *, struct dentry *, int datasync);
+       int (*fsync) (struct file *, int datasync);
        int (*aio_fsync) (struct kiocb *, int datasync);
        int (*fasync) (int, struct file *, int);
        int (*lock) (struct file *, int, struct file_lock *);
@@ -429,8 +429,9 @@ check_flags:                no
 implementations.  If your fs is not using generic_file_llseek, you
 need to acquire and release the appropriate locks in your ->llseek().
 For many filesystems, it is probably safe to acquire the inode
-semaphore.  Note some filesystems (i.e. remote ones) provide no
-protection for i_size so you will need to use the BKL.
+mutex or just to use i_size_read() instead.
+Note: this does not protect the file->f_pos against concurrent modifications
+since this is something the userspace has to take care about.
 
 Note: ext2_release() was *the* source of contention on fs-intensive
 loads and dropping BKL on ->release() helps to get rid of that (we still
@@ -460,13 +461,6 @@ in sys_read() and friends.
 
 --------------------------- dquot_operations -------------------------------
 prototypes:
-       int (*initialize) (struct inode *, int);
-       int (*drop) (struct inode *);
-       int (*alloc_space) (struct inode *, qsize_t, int);
-       int (*alloc_inode) (const struct inode *, unsigned long);
-       int (*free_space) (struct inode *, qsize_t);
-       int (*free_inode) (const struct inode *, unsigned long);
-       int (*transfer) (struct inode *, struct iattr *);
        int (*write_dquot) (struct dquot *);
        int (*acquire_dquot) (struct dquot *);
        int (*release_dquot) (struct dquot *);
@@ -479,13 +473,6 @@ a proper locking wrt the filesystem and call the generic quota operations.
 What filesystem should expect from the generic quota functions:
 
                FS recursion    Held locks when called
-initialize:    yes             maybe dqonoff_sem
-drop:          yes             -
-alloc_space:   ->mark_dirty()  -
-alloc_inode:   ->mark_dirty()  -
-free_space:    ->mark_dirty()  -
-free_inode:    ->mark_dirty()  -
-transfer:      yes             -
 write_dquot:   yes             dqonoff_sem or dqptr_sem
 acquire_dquot: yes             dqonoff_sem or dqptr_sem
 release_dquot: yes             dqonoff_sem or dqptr_sem
@@ -495,10 +482,6 @@ write_info:        yes             dqonoff_sem
 FS recursion means calling ->quota_read() and ->quota_write() from superblock
 operations.
 
-->alloc_space(), ->alloc_inode(), ->free_space(), ->free_inode() are called
-only directly by the filesystem and do not call any fs functions only
-the ->mark_dirty() operation.
-
 More details about quota locking can be found in fs/dquot.c.
 
 --------------------------- vm_operations_struct -----------------------------