From 4f819a7899b06afcd7623ab9d00fd81503ad3e24 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Sun, 12 Sep 2010 19:05:56 +0200 Subject: BKL: Remove BKL from isofs As in other file systems, we can replace the big kernel lock with a private mutex in isofs. This means we can now access multiple file systems concurrently, but it also means that we serialize readdir and lookup across sleeping operations which previously released the big kernel lock. This should not matter though, as these operations are in practice serialized through the hardware access. The isofs_get_blocks functions now does not take any lock any more, it used to recursively get the BKL. After looking at the code for hours, I convinced myself that it was never needed here anyway, because it only reads constant fields of the inode and writes to a buffer head array that is at this time only visible to the caller. The get_sb and fill_super operations do not need the locking at all because they operate on a file system that is either about to be created or to be destroyed but in either case is not visible to other threads. Signed-off-by: Arnd Bergmann --- fs/isofs/dir.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'fs/isofs/dir.c') diff --git a/fs/isofs/dir.c b/fs/isofs/dir.c index e0aca9a..0542b6e 100644 --- a/fs/isofs/dir.c +++ b/fs/isofs/dir.c @@ -10,7 +10,6 @@ * * isofs directory handling functions */ -#include #include #include "isofs.h" @@ -255,18 +254,19 @@ static int isofs_readdir(struct file *filp, char *tmpname; struct iso_directory_record *tmpde; struct inode *inode = filp->f_path.dentry->d_inode; + struct isofs_sb_info *sbi = ISOFS_SB(inode->i_sb); tmpname = (char *)__get_free_page(GFP_KERNEL); if (tmpname == NULL) return -ENOMEM; - lock_kernel(); + mutex_lock(&sbi->s_mutex); tmpde = (struct iso_directory_record *) (tmpname+1024); result = do_isofs_readdir(inode, filp, dirent, filldir, tmpname, tmpde); free_page((unsigned long) tmpname); - unlock_kernel(); + mutex_unlock(&sbi->s_mutex); return result; } -- cgit v1.1