From a16877ca9cec211708a161057a7cbfbf2cbc3a53 Mon Sep 17 00:00:00 2001 From: Pavel Emelyanov Date: Mon, 1 Oct 2007 14:41:11 -0700 Subject: Cleanup macros for distinguishing mandatory locks The combination of S_ISGID bit set and S_IXGRP bit unset is used to mark the inode as "mandatory lockable" and there's a macro for this check called MANDATORY_LOCK(inode). However, fs/locks.c and some filesystems still perform the explicit i_mode checking. Besides, Andrew pointed out, that this macro is buggy itself, as it dereferences the inode arg twice. Convert this macro into static inline function and switch its users to it, making the code shorter and more readable. The __mandatory_lock() helper is to be used in places where the IS_MANDLOCK() for superblock is already known to be true. Signed-off-by: Pavel Emelyanov Cc: Trond Myklebust Cc: "J. Bruce Fields" Cc: David Howells Cc: Eric Van Hensbergen Cc: Ron Minnich Cc: Latchesar Ionkov Cc: Steven Whitehouse Signed-off-by: Andrew Morton --- include/linux/fs.h | 21 +++++++++++++++++---- 1 file changed, 17 insertions(+), 4 deletions(-) (limited to 'include') diff --git a/include/linux/fs.h b/include/linux/fs.h index 16421f662a7a..f5075e0e7301 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1369,12 +1369,25 @@ extern int locks_mandatory_area(int, struct inode *, struct file *, loff_t, size * Candidates for mandatory locking have the setgid bit set * but no group execute bit - an otherwise meaningless combination. */ -#define MANDATORY_LOCK(inode) \ - (IS_MANDLOCK(inode) && ((inode)->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID) + +static inline int __mandatory_lock(struct inode *ino) +{ + return (ino->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID; +} + +/* + * ... and these candidates should be on MS_MANDLOCK mounted fs, + * otherwise these will be advisory locks + */ + +static inline int mandatory_lock(struct inode *ino) +{ + return IS_MANDLOCK(ino) && __mandatory_lock(ino); +} static inline int locks_verify_locked(struct inode *inode) { - if (MANDATORY_LOCK(inode)) + if (mandatory_lock(inode)) return locks_mandatory_locked(inode); return 0; } @@ -1385,7 +1398,7 @@ static inline int locks_verify_truncate(struct inode *inode, struct file *filp, loff_t size) { - if (inode->i_flock && MANDATORY_LOCK(inode)) + if (inode->i_flock && mandatory_lock(inode)) return locks_mandatory_area( FLOCK_VERIFY_WRITE, inode, filp, size < inode->i_size ? size : inode->i_size, -- cgit v1.2.1 From 7f8ada98d9edd83d6ebd01e431e15b024a4a3dc4 Mon Sep 17 00:00:00 2001 From: Pavel Emelyanov Date: Mon, 1 Oct 2007 14:41:15 -0700 Subject: Rework /proc/locks via seq_files and seq_list helpers Currently /proc/locks is shown with a proc_read function, but its behavior is rather complex as it has to manually handle current offset and buffer length. On the other hand, files that show objects from lists can be easily reimplemented using the sequential files and the seq_list_XXX() helpers. This saves (as usually) 16 lines of code and more than 200 from the .text section. [akpm@linux-foundation.org: no externs in C] [akpm@linux-foundation.org: warning fixes] Signed-off-by: Pavel Emelyanov Cc: "J. Bruce Fields" Cc: Trond Myklebust Signed-off-by: Andrew Morton --- include/linux/fs.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include') diff --git a/include/linux/fs.h b/include/linux/fs.h index f5075e0e7301..4f1e8cebea78 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -883,6 +883,7 @@ extern int vfs_setlease(struct file *, long, struct file_lock **); extern int lease_modify(struct file_lock **, int); extern int lock_may_read(struct inode *, loff_t start, unsigned long count); extern int lock_may_write(struct inode *, loff_t start, unsigned long count); +extern struct seq_operations locks_seq_operations; struct fasync_struct { int magic; -- cgit v1.2.1