From bbd6851a3213a525128473e978b692ab6ac11aba Mon Sep 17 00:00:00 2001 From: Al Viro Date: Wed, 6 May 2009 10:43:07 -0400 Subject: Push lock_super() into the ->remount_fs() of filesystems that care about it Note that since we can't run into contention between remount_fs and write_super (due to exclusion on s_umount), we have to care only about filesystems that touch lock_super() on their own. Out of those ext3, ext4, hpfs, sysv and ufs do need it; fat doesn't since its ->remount_fs() only accesses assign-once data (basically, it's "we have no atime on directories and only have atime on files for vfat; force nodiratime and possibly noatime into *flags"). [folded a build fix from hch] Signed-off-by: Al Viro diff --git a/fs/ext3/super.c b/fs/ext3/super.c index 546b8d7..e213a26 100644 --- a/fs/ext3/super.c +++ b/fs/ext3/super.c @@ -2491,6 +2491,7 @@ static int ext3_remount (struct super_block * sb, int * flags, char * data) #endif /* Store the original options */ + lock_super(sb); old_sb_flags = sb->s_flags; old_opts.s_mount_opt = sbi->s_mount_opt; old_opts.s_resuid = sbi->s_resuid; @@ -2598,6 +2599,7 @@ static int ext3_remount (struct super_block * sb, int * flags, char * data) old_opts.s_qf_names[i] != sbi->s_qf_names[i]) kfree(old_opts.s_qf_names[i]); #endif + unlock_super(sb); return 0; restore_opts: sb->s_flags = old_sb_flags; @@ -2614,6 +2616,7 @@ restore_opts: sbi->s_qf_names[i] = old_opts.s_qf_names[i]; } #endif + unlock_super(sb); return err; } diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 1d4180b..a9c6834 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -3421,6 +3421,7 @@ static int ext4_remount(struct super_block *sb, int *flags, char *data) #endif /* Store the original options */ + lock_super(sb); old_sb_flags = sb->s_flags; old_opts.s_mount_opt = sbi->s_mount_opt; old_opts.s_resuid = sbi->s_resuid; @@ -3554,6 +3555,7 @@ static int ext4_remount(struct super_block *sb, int *flags, char *data) old_opts.s_qf_names[i] != sbi->s_qf_names[i]) kfree(old_opts.s_qf_names[i]); #endif + unlock_super(sb); return 0; restore_opts: @@ -3573,6 +3575,7 @@ restore_opts: sbi->s_qf_names[i] = old_opts.s_qf_names[i]; } #endif + unlock_super(sb); return err; } diff --git a/fs/hpfs/super.c b/fs/hpfs/super.c index 437a32e..f68193c 100644 --- a/fs/hpfs/super.c +++ b/fs/hpfs/super.c @@ -398,6 +398,7 @@ static int hpfs_remount_fs(struct super_block *s, int *flags, char *data) *flags |= MS_NOATIME; + lock_super(s); uid = sbi->sb_uid; gid = sbi->sb_gid; umask = 0777 & ~sbi->sb_mode; lowercase = sbi->sb_lowercase; conv = sbi->sb_conv; @@ -430,9 +431,11 @@ static int hpfs_remount_fs(struct super_block *s, int *flags, char *data) replace_mount_options(s, new_opts); + unlock_super(s); return 0; out_err: + unlock_super(s); kfree(new_opts); return -EINVAL; } diff --git a/fs/super.c b/fs/super.c index bdd7158..2a49fed 100644 --- a/fs/super.c +++ b/fs/super.c @@ -556,9 +556,7 @@ int do_remount_sb(struct super_block *sb, int flags, void *data, int force) remount_rw = !(flags & MS_RDONLY) && (sb->s_flags & MS_RDONLY); if (sb->s_op->remount_fs) { - lock_super(sb); retval = sb->s_op->remount_fs(sb, &flags, data); - unlock_super(sb); if (retval) return retval; } diff --git a/fs/sysv/inode.c b/fs/sysv/inode.c index a818986..e0a39f1 100644 --- a/fs/sysv/inode.c +++ b/fs/sysv/inode.c @@ -61,10 +61,12 @@ clean: static int sysv_remount(struct super_block *sb, int *flags, char *data) { struct sysv_sb_info *sbi = SYSV_SB(sb); + lock_super(sb); if (sbi->s_forced_ro) *flags |= MS_RDONLY; if (!(*flags & MS_RDONLY)) sb->s_dirt = 1; + unlock_super(sb); return 0; } diff --git a/fs/ufs/super.c b/fs/ufs/super.c index 2b4d2b6..a5ecabf 100644 --- a/fs/ufs/super.c +++ b/fs/ufs/super.c @@ -1181,6 +1181,7 @@ static int ufs_remount (struct super_block *sb, int *mount_flags, char *data) unsigned new_mount_opt, ufstype; unsigned flags; + lock_super(sb); uspi = UFS_SB(sb)->s_uspi; flags = UFS_SB(sb)->s_flags; usb1 = ubh_get_usb_first(uspi); @@ -1193,17 +1194,21 @@ static int ufs_remount (struct super_block *sb, int *mount_flags, char *data) ufstype = UFS_SB(sb)->s_mount_opt & UFS_MOUNT_UFSTYPE; new_mount_opt = 0; ufs_set_opt (new_mount_opt, ONERROR_LOCK); - if (!ufs_parse_options (data, &new_mount_opt)) + if (!ufs_parse_options (data, &new_mount_opt)) { + unlock_super(sb); return -EINVAL; + } if (!(new_mount_opt & UFS_MOUNT_UFSTYPE)) { new_mount_opt |= ufstype; } else if ((new_mount_opt & UFS_MOUNT_UFSTYPE) != ufstype) { printk("ufstype can't be changed during remount\n"); + unlock_super(sb); return -EINVAL; } if ((*mount_flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) { UFS_SB(sb)->s_mount_opt = new_mount_opt; + unlock_super(sb); return 0; } @@ -1228,6 +1233,7 @@ static int ufs_remount (struct super_block *sb, int *mount_flags, char *data) #ifndef CONFIG_UFS_FS_WRITE printk("ufs was compiled with read-only support, " "can't be mounted as read-write\n"); + unlock_super(sb); return -EINVAL; #else if (ufstype != UFS_MOUNT_UFSTYPE_SUN && @@ -1236,16 +1242,19 @@ static int ufs_remount (struct super_block *sb, int *mount_flags, char *data) ufstype != UFS_MOUNT_UFSTYPE_SUNx86 && ufstype != UFS_MOUNT_UFSTYPE_UFS2) { printk("this ufstype is read-only supported\n"); + unlock_super(sb); return -EINVAL; } if (!ufs_read_cylinder_structures(sb)) { printk("failed during remounting\n"); + unlock_super(sb); return -EPERM; } sb->s_flags &= ~MS_RDONLY; #endif } UFS_SB(sb)->s_mount_opt = new_mount_opt; + unlock_super(sb); return 0; } -- cgit v0.10.2