diff options
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/dcache.c | 6 | ||||
| -rw-r--r-- | fs/ext4/super.c | 4 | ||||
| -rw-r--r-- | fs/jfs/xattr.c | 10 | ||||
| -rw-r--r-- | fs/namespace.c | 28 |
4 files changed, 38 insertions, 10 deletions
diff --git a/fs/dcache.c b/fs/dcache.c index 750ddc627855..94f7541c154d 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -1932,10 +1932,12 @@ struct dentry *d_make_root(struct inode *root_inode) static const struct qstr name = QSTR_INIT("/", 1); res = __d_alloc(root_inode->i_sb, &name); - if (res) + if (res) { + res->d_flags |= DCACHE_RCUACCESS; d_instantiate(res, root_inode); - else + } else { iput(root_inode); + } } return res; } diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 53d28a0ca6eb..71c9104a7779 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -2101,7 +2101,7 @@ static int ext4_check_descriptors(struct super_block *sb, struct ext4_sb_info *sbi = EXT4_SB(sb); ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block); ext4_fsblk_t last_block; - ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0) + 1; + ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0); ext4_fsblk_t block_bitmap; ext4_fsblk_t inode_bitmap; ext4_fsblk_t inode_table; @@ -3770,13 +3770,13 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) goto failed_mount2; } } + sbi->s_gdb_count = db_count; if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) { ext4_msg(sb, KERN_ERR, "group descriptors corrupted!"); ret = -EFSCORRUPTED; goto failed_mount2; } - sbi->s_gdb_count = db_count; get_random_bytes(&sbi->s_next_generation, sizeof(u32)); spin_lock_init(&sbi->s_next_gen_lock); diff --git a/fs/jfs/xattr.c b/fs/jfs/xattr.c index 48b15a6e5558..40a26a542341 100644 --- a/fs/jfs/xattr.c +++ b/fs/jfs/xattr.c @@ -493,15 +493,17 @@ static int ea_get(struct inode *inode, struct ea_buffer *ea_buf, int min_size) if (size > PSIZE) { /* * To keep the rest of the code simple. Allocate a - * contiguous buffer to work with + * contiguous buffer to work with. Make the buffer large + * enough to make use of the whole extent. */ - ea_buf->xattr = kmalloc(size, GFP_KERNEL); + ea_buf->max_size = (size + sb->s_blocksize - 1) & + ~(sb->s_blocksize - 1); + + ea_buf->xattr = kmalloc(ea_buf->max_size, GFP_KERNEL); if (ea_buf->xattr == NULL) return -ENOMEM; ea_buf->flag = EA_MALLOC; - ea_buf->max_size = (size + sb->s_blocksize - 1) & - ~(sb->s_blocksize - 1); if (ea_size == 0) return 0; diff --git a/fs/namespace.c b/fs/namespace.c index b3d8d3d8f05f..297ce252f39a 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -605,12 +605,21 @@ int __legitimize_mnt(struct vfsmount *bastard, unsigned seq) return 0; mnt = real_mount(bastard); mnt_add_count(mnt, 1); + smp_mb(); // see mntput_no_expire() if (likely(!read_seqretry(&mount_lock, seq))) return 0; if (bastard->mnt_flags & MNT_SYNC_UMOUNT) { mnt_add_count(mnt, -1); return 1; } + lock_mount_hash(); + if (unlikely(bastard->mnt_flags & MNT_DOOMED)) { + mnt_add_count(mnt, -1); + unlock_mount_hash(); + return 1; + } + unlock_mount_hash(); + /* caller will mntput() */ return -1; } @@ -1142,12 +1151,27 @@ static DECLARE_DELAYED_WORK(delayed_mntput_work, delayed_mntput); static void mntput_no_expire(struct mount *mnt) { rcu_read_lock(); - mnt_add_count(mnt, -1); - if (likely(mnt->mnt_ns)) { /* shouldn't be the last one */ + if (likely(READ_ONCE(mnt->mnt_ns))) { + /* + * Since we don't do lock_mount_hash() here, + * ->mnt_ns can change under us. However, if it's + * non-NULL, then there's a reference that won't + * be dropped until after an RCU delay done after + * turning ->mnt_ns NULL. So if we observe it + * non-NULL under rcu_read_lock(), the reference + * we are dropping is not the final one. + */ + mnt_add_count(mnt, -1); rcu_read_unlock(); return; } lock_mount_hash(); + /* + * make sure that if __legitimize_mnt() has not seen us grab + * mount_lock, we'll see their refcount increment here. + */ + smp_mb(); + mnt_add_count(mnt, -1); if (mnt_get_count(mnt)) { rcu_read_unlock(); unlock_mount_hash(); |