From db71922217a214e5c9268448e537b54fc1f301ea Mon Sep 17 00:00:00 2001 From: Jan Blunck Date: Sun, 15 Aug 2010 22:51:10 +0200 Subject: BKL: Explicitly add BKL around get_sb/fill_super This patch is a preparation necessary to remove the BKL from do_new_mount(). It explicitly adds calls to lock_kernel()/unlock_kernel() around get_sb/fill_super operations for filesystems that still uses the BKL. I've read through all the code formerly covered by the BKL inside do_kern_mount() and have satisfied myself that it doesn't need the BKL any more. do_kern_mount() is already called without the BKL when mounting the rootfs and in nfsctl. do_kern_mount() calls vfs_kern_mount(), which is called from various places without BKL: simple_pin_fs(), nfs_do_clone_mount() through nfs_follow_mountpoint(), afs_mntpt_do_automount() through afs_mntpt_follow_link(). Both later functions are actually the filesystems follow_link inode operation. vfs_kern_mount() is calling the specified get_sb function and lets the filesystem do its job by calling the given fill_super function. Therefore I think it is safe to push down the BKL from the VFS to the low-level filesystems get_sb/fill_super operation. [arnd: do not add the BKL to those file systems that already don't use it elsewhere] Signed-off-by: Jan Blunck Signed-off-by: Arnd Bergmann Cc: Matthew Wilcox Cc: Christoph Hellwig --- fs/ecryptfs/main.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'fs/ecryptfs') diff --git a/fs/ecryptfs/main.c b/fs/ecryptfs/main.c index cbd4e18adb20..c4af92fa12c3 100644 --- a/fs/ecryptfs/main.c +++ b/fs/ecryptfs/main.c @@ -36,6 +36,7 @@ #include #include #include +#include /* For lock_kernel() */ #include "ecryptfs_kernel.h" /** @@ -550,6 +551,7 @@ static int ecryptfs_get_sb(struct file_system_type *fs_type, int flags, const char *err = "Getting sb failed"; int rc; + lock_kernel(); sbi = kmem_cache_zalloc(ecryptfs_sb_info_cache, GFP_KERNEL); if (!sbi) { rc = -ENOMEM; @@ -608,6 +610,7 @@ static int ecryptfs_get_sb(struct file_system_type *fs_type, int flags, goto out; } simple_set_mnt(mnt, s); + unlock_kernel(); return 0; out: @@ -616,6 +619,7 @@ out: kmem_cache_free(ecryptfs_sb_info_cache, sbi); } printk(KERN_ERR "%s; rc = [%d]\n", err, rc); + unlock_kernel(); return rc; } -- cgit v1.2.3 From 18dfe89d7c394b56e20e06dde8b7a80ff96cf02c Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Thu, 16 Sep 2010 15:35:54 +0200 Subject: BKL: Remove BKL from ecryptfs The BKL is only used in fill_super, which is protected by the superblocks s_umount rw_semaphorei, and in fasync, which does not do anything that could require the BKL. Therefore it is safe to remove the BKL entirely. Signed-off-by: Arnd Bergmann Cc: Dustin Kirkland Cc: Tyler Hicks Cc: ecryptfs-devel@lists.launchpad.net --- fs/ecryptfs/file.c | 3 --- fs/ecryptfs/main.c | 4 ---- 2 files changed, 7 deletions(-) (limited to 'fs/ecryptfs') diff --git a/fs/ecryptfs/file.c b/fs/ecryptfs/file.c index 622c95140802..2b9a644b7583 100644 --- a/fs/ecryptfs/file.c +++ b/fs/ecryptfs/file.c @@ -31,7 +31,6 @@ #include #include #include -#include #include "ecryptfs_kernel.h" /** @@ -284,11 +283,9 @@ static int ecryptfs_fasync(int fd, struct file *file, int flag) int rc = 0; struct file *lower_file = NULL; - lock_kernel(); lower_file = ecryptfs_file_to_lower(file); if (lower_file->f_op && lower_file->f_op->fasync) rc = lower_file->f_op->fasync(fd, lower_file, flag); - unlock_kernel(); return rc; } diff --git a/fs/ecryptfs/main.c b/fs/ecryptfs/main.c index c4af92fa12c3..cbd4e18adb20 100644 --- a/fs/ecryptfs/main.c +++ b/fs/ecryptfs/main.c @@ -36,7 +36,6 @@ #include #include #include -#include /* For lock_kernel() */ #include "ecryptfs_kernel.h" /** @@ -551,7 +550,6 @@ static int ecryptfs_get_sb(struct file_system_type *fs_type, int flags, const char *err = "Getting sb failed"; int rc; - lock_kernel(); sbi = kmem_cache_zalloc(ecryptfs_sb_info_cache, GFP_KERNEL); if (!sbi) { rc = -ENOMEM; @@ -610,7 +608,6 @@ static int ecryptfs_get_sb(struct file_system_type *fs_type, int flags, goto out; } simple_set_mnt(mnt, s); - unlock_kernel(); return 0; out: @@ -619,7 +616,6 @@ out: kmem_cache_free(ecryptfs_sb_info_cache, sbi); } printk(KERN_ERR "%s; rc = [%d]\n", err, rc); - unlock_kernel(); return rc; } -- cgit v1.2.3