Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754114Ab0DLUmt (ORCPT ); Mon, 12 Apr 2010 16:42:49 -0400 Received: from cantor.suse.de ([195.135.220.2]:38975 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753993Ab0DLUmH (ORCPT ); Mon, 12 Apr 2010 16:42:07 -0400 From: Jan Blunck To: Jan Kara , tytso@mit.edu Cc: Linux-Kernel Mailinglist , linux-ext4@vger.kernel.org, Frederic Weisbecker , Arnd Bergmann , Jan Blunck , Andi Kleen , Jan Kara , OGAWA Hirofumi Subject: [PATCH 5/5] ext2: Add ext2_sb_info s_lock spinlock Date: Mon, 12 Apr 2010 22:41:45 +0200 Message-Id: <1271104905-8804-6-git-send-email-jblunck@suse.de> X-Mailer: git-send-email 1.6.4.2 In-Reply-To: <1271104905-8804-1-git-send-email-jblunck@suse.de> References: <1271104905-8804-1-git-send-email-jblunck@suse.de> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7418 Lines: 222 Add a spinlock that protects against concurrent modifications of s_mount_state, s_blocks_last, s_overhead_last and the content of the superblock's buffer pointed to by sbi->s_es. This is a preparation patch for removing the BKL from ext2 in the next patch. Signed-off-by: Jan Blunck Cc: Andi Kleen Cc: Jan Kara Cc: OGAWA Hirofumi --- fs/ext2/inode.c | 2 ++ fs/ext2/super.c | 31 +++++++++++++++++++++++++++++-- include/linux/ext2_fs_sb.h | 6 ++++++ 3 files changed, 37 insertions(+), 2 deletions(-) diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c index fc13cc1..5d15442 100644 --- a/fs/ext2/inode.c +++ b/fs/ext2/inode.c @@ -1407,9 +1407,11 @@ static int __ext2_write_inode(struct inode *inode, int do_sync) * created, add a flag to the superblock. */ lock_kernel(); + spin_lock(&EXT2_SB(sb)->s_lock); ext2_update_dynamic_rev(sb); EXT2_SET_RO_COMPAT_FEATURE(sb, EXT2_FEATURE_RO_COMPAT_LARGE_FILE); + spin_unlock(&EXT2_SB(sb)->s_lock); unlock_kernel(); ext2_write_super(sb); } diff --git a/fs/ext2/super.c b/fs/ext2/super.c index b01c491..34d7a62 100644 --- a/fs/ext2/super.c +++ b/fs/ext2/super.c @@ -52,8 +52,10 @@ void ext2_error (struct super_block * sb, const char * function, struct ext2_super_block *es = sbi->s_es; if (!(sb->s_flags & MS_RDONLY)) { + spin_lock(&sbi->s_lock); sbi->s_mount_state |= EXT2_ERROR_FS; es->s_state |= cpu_to_le16(EXT2_ERROR_FS); + spin_unlock(&sbi->s_lock); ext2_sync_super(sb, es); } @@ -84,6 +86,9 @@ void ext2_msg(struct super_block *sb, const char *prefix, va_end(args); } +/* + * This must be called with sbi->s_lock held. + */ void ext2_update_dynamic_rev(struct super_block *sb) { struct ext2_super_block *es = EXT2_SB(sb)->s_es; @@ -124,7 +129,9 @@ static void ext2_put_super (struct super_block * sb) if (!(sb->s_flags & MS_RDONLY)) { struct ext2_super_block *es = sbi->s_es; + spin_lock(&sbi->s_lock); es->s_state = cpu_to_le16(sbi->s_mount_state); + spin_unlock(&sbi->s_lock); ext2_sync_super(sb, es); } db_count = sbi->s_gdb_count; @@ -209,6 +216,7 @@ static int ext2_show_options(struct seq_file *seq, struct vfsmount *vfs) struct ext2_super_block *es = sbi->s_es; unsigned long def_mount_opts; + spin_lock(&sbi->s_lock); def_mount_opts = le32_to_cpu(es->s_default_mount_opts); if (sbi->s_sb_block != 1) @@ -281,6 +289,7 @@ static int ext2_show_options(struct seq_file *seq, struct vfsmount *vfs) if (!test_opt(sb, RESERVATION)) seq_puts(seq, ",noreservation"); + spin_unlock(&sbi->s_lock); return 0; } @@ -766,6 +775,8 @@ static int ext2_fill_super(struct super_block *sb, void *data, int silent) sb->s_fs_info = sbi; sbi->s_sb_block = sb_block; + spin_lock_init(&sbi->s_lock); + /* * See what the current blocksize for the device is, and * use that as the blocksize. Otherwise (or if the blocksize @@ -1137,12 +1148,16 @@ static void ext2_commit_super (struct super_block * sb, sb->s_dirt = 0; } -static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es) +static void ext2_sync_super(struct super_block *sb, + struct ext2_super_block *es) { ext2_clear_super_error(sb); + spin_lock(&EXT2_SB(sb)->s_lock); es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb)); es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb)); es->s_wtime = cpu_to_le32(get_seconds()); + /* unlock before we do IO */ + spin_unlock(&EXT2_SB(sb)->s_lock); mark_buffer_dirty(EXT2_SB(sb)->s_sbh); sync_dirty_buffer(EXT2_SB(sb)->s_sbh); sb->s_dirt = 0; @@ -1158,19 +1173,22 @@ static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es) * may have been checked while mounted and e2fsck may have * set s_state to EXT2_VALID_FS after some corrections. */ - static int ext2_sync_fs(struct super_block *sb, int wait) { + struct ext2_sb_info *sbi = EXT2_SB(sb); struct ext2_super_block *es = EXT2_SB(sb)->s_es; struct buffer_head *sbh = EXT2_SB(sb)->s_sbh; lock_kernel(); + spin_lock(&sbi->s_lock); if (es->s_state & cpu_to_le16(EXT2_VALID_FS)) { ext2_debug("setting valid to 0\n"); es->s_state &= cpu_to_le16(~EXT2_VALID_FS); + spin_unlock(&sbi->s_lock); ext2_sync_super(sb, es); } else { ext2_commit_super(sb, es); + spin_unlock(&sbi->s_lock); } sb->s_dirt = 0; unlock_kernel(); @@ -1197,6 +1215,7 @@ static int ext2_remount (struct super_block * sb, int * flags, char * data) int err; lock_kernel(); + spin_lock(&sbi->s_lock); /* Store the old options */ old_sb_flags = sb->s_flags; @@ -1235,12 +1254,14 @@ static int ext2_remount (struct super_block * sb, int * flags, char * data) sbi->s_mount_opt |= old_mount_opt & EXT2_MOUNT_XIP; } if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) { + spin_unlock(&sbi->s_lock); unlock_kernel(); return 0; } if (*flags & MS_RDONLY) { if (le16_to_cpu(es->s_state) & EXT2_VALID_FS || !(sbi->s_mount_state & EXT2_VALID_FS)) { + spin_unlock(&sbi->s_lock); unlock_kernel(); return 0; } @@ -1250,6 +1271,7 @@ static int ext2_remount (struct super_block * sb, int * flags, char * data) */ es->s_state = cpu_to_le16(sbi->s_mount_state); es->s_mtime = cpu_to_le32(get_seconds()); + spin_unlock(&sbi->s_lock); ext2_sync_super(sb, es); } else { __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb, @@ -1270,6 +1292,7 @@ static int ext2_remount (struct super_block * sb, int * flags, char * data) sbi->s_mount_state = le16_to_cpu(es->s_state); if (!ext2_setup_super (sb, es, 0)) sb->s_flags &= ~MS_RDONLY; + spin_unlock(&sbi->s_lock); ext2_write_super(sb); } unlock_kernel(); @@ -1279,6 +1302,7 @@ restore_opts: sbi->s_resuid = old_opts.s_resuid; sbi->s_resgid = old_opts.s_resgid; sb->s_flags = old_sb_flags; + spin_unlock(&sbi->s_lock); unlock_kernel(); return err; } @@ -1290,6 +1314,8 @@ static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf) struct ext2_super_block *es = sbi->s_es; u64 fsid; + spin_lock(&sbi->s_lock); + if (test_opt (sb, MINIX_DF)) sbi->s_overhead_last = 0; else if (sbi->s_blocks_last != le32_to_cpu(es->s_blocks_count)) { @@ -1344,6 +1370,7 @@ static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf) le64_to_cpup((void *)es->s_uuid + sizeof(u64)); buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL; buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL; + spin_unlock(&sbi->s_lock); return 0; } diff --git a/include/linux/ext2_fs_sb.h b/include/linux/ext2_fs_sb.h index 1cdb663..dbc5934 100644 --- a/include/linux/ext2_fs_sb.h +++ b/include/linux/ext2_fs_sb.h @@ -106,6 +106,12 @@ struct ext2_sb_info { spinlock_t s_rsv_window_lock; struct rb_root s_rsv_window_root; struct ext2_reserve_window_node s_rsv_window_head; + /* + * protects against concurrent modifications of s_mount_state, + * s_blocks_last, s_overhead_last and the content of superblock's + * buffer pointed to by sbi->s_es. + */ + spinlock_t s_lock; }; static inline spinlock_t * -- 1.6.4.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/