diff options
| -rw-r--r-- | fs/afs/callback.c | 12 | ||||
| -rw-r--r-- | fs/ext4/inode.c | 44 | ||||
| -rw-r--r-- | fs/inode.c | 112 | ||||
| -rw-r--r-- | include/linux/fs.h | 3 |
4 files changed, 130 insertions, 41 deletions
diff --git a/fs/afs/callback.c b/fs/afs/callback.c index 2dca8df1a18d..0dcbd40732d1 100644 --- a/fs/afs/callback.c +++ b/fs/afs/callback.c @@ -252,6 +252,7 @@ static void afs_break_one_callback(struct afs_server *server, struct afs_vnode *vnode; struct inode *inode; + rcu_read_lock(); read_lock(&server->cb_break_lock); hlist_for_each_entry(vi, &server->cb_volumes, srv_link) { if (vi->vid < fid->vid) @@ -287,12 +288,16 @@ static void afs_break_one_callback(struct afs_server *server, } else { data.volume = NULL; data.fid = *fid; - inode = ilookup5_nowait(cbi->sb, fid->vnode, - afs_iget5_test, &data); + + /* See if we can find a matching inode - even an I_NEW + * inode needs to be marked as it can have its callback + * broken before we finish setting up the local inode. + */ + inode = find_inode_rcu(cbi->sb, fid->vnode, + afs_iget5_test, &data); if (inode) { vnode = AFS_FS_I(inode); afs_break_callback(vnode, afs_cb_break_for_callback); - iput(inode); } else { trace_afs_cb_miss(fid, afs_cb_break_for_callback); } @@ -301,6 +306,7 @@ static void afs_break_one_callback(struct afs_server *server, out: read_unlock(&server->cb_break_lock); + rcu_read_unlock(); } /* diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 2a4aae6acdcb..2bbb55d05bb7 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -4860,21 +4860,22 @@ static int ext4_inode_blocks_set(handle_t *handle, return 0; } -struct other_inode { - unsigned long orig_ino; - struct ext4_inode *raw_inode; -}; - -static int other_inode_match(struct inode * inode, unsigned long ino, - void *data) +static void __ext4_update_other_inode_time(struct super_block *sb, + unsigned long orig_ino, + unsigned long ino, + struct ext4_inode *raw_inode) { - struct other_inode *oi = (struct other_inode *) data; + struct inode *inode; + + inode = find_inode_by_ino_rcu(sb, ino); + if (!inode) + return; - if ((inode->i_ino != ino) || - (inode->i_state & (I_FREEING | I_WILL_FREE | I_NEW | + if ((inode->i_state & (I_FREEING | I_WILL_FREE | I_NEW | I_DIRTY_INODE)) || ((inode->i_state & I_DIRTY_TIME) == 0)) - return 0; + return; + spin_lock(&inode->i_lock); if (((inode->i_state & (I_FREEING | I_WILL_FREE | I_NEW | I_DIRTY_INODE)) == 0) && @@ -4885,16 +4886,15 @@ static int other_inode_match(struct inode * inode, unsigned long ino, spin_unlock(&inode->i_lock); spin_lock(&ei->i_raw_lock); - EXT4_INODE_SET_XTIME(i_ctime, inode, oi->raw_inode); - EXT4_INODE_SET_XTIME(i_mtime, inode, oi->raw_inode); - EXT4_INODE_SET_XTIME(i_atime, inode, oi->raw_inode); - ext4_inode_csum_set(inode, oi->raw_inode, ei); + EXT4_INODE_SET_XTIME(i_ctime, inode, raw_inode); + EXT4_INODE_SET_XTIME(i_mtime, inode, raw_inode); + EXT4_INODE_SET_XTIME(i_atime, inode, raw_inode); + ext4_inode_csum_set(inode, raw_inode, ei); spin_unlock(&ei->i_raw_lock); - trace_ext4_other_inode_update_time(inode, oi->orig_ino); - return -1; + trace_ext4_other_inode_update_time(inode, orig_ino); + return; } spin_unlock(&inode->i_lock); - return -1; } /* @@ -4904,24 +4904,24 @@ static int other_inode_match(struct inode * inode, unsigned long ino, static void ext4_update_other_inodes_time(struct super_block *sb, unsigned long orig_ino, char *buf) { - struct other_inode oi; unsigned long ino; int i, inodes_per_block = EXT4_SB(sb)->s_inodes_per_block; int inode_size = EXT4_INODE_SIZE(sb); - oi.orig_ino = orig_ino; /* * Calculate the first inode in the inode table block. Inode * numbers are one-based. That is, the first inode in a block * (assuming 4k blocks and 256 byte inodes) is (n*16 + 1). */ ino = ((orig_ino - 1) & ~(inodes_per_block - 1)) + 1; + rcu_read_lock(); for (i = 0; i < inodes_per_block; i++, ino++, buf += inode_size) { if (ino == orig_ino) continue; - oi.raw_inode = (struct ext4_inode *) buf; - (void) find_inode_nowait(sb, ino, other_inode_match, &oi); + __ext4_update_other_inode_time(sb, orig_ino, ino, + (struct ext4_inode *)buf); } + rcu_read_unlock(); } /* diff --git a/fs/inode.c b/fs/inode.c index 93d9252a00ab..b7bd7162c902 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -497,7 +497,7 @@ void __insert_inode_hash(struct inode *inode, unsigned long hashval) spin_lock(&inode_hash_lock); spin_lock(&inode->i_lock); - hlist_add_head(&inode->i_hash, b); + hlist_add_head_rcu(&inode->i_hash, b); spin_unlock(&inode->i_lock); spin_unlock(&inode_hash_lock); } @@ -513,7 +513,7 @@ void __remove_inode_hash(struct inode *inode) { spin_lock(&inode_hash_lock); spin_lock(&inode->i_lock); - hlist_del_init(&inode->i_hash); + hlist_del_init_rcu(&inode->i_hash); spin_unlock(&inode->i_lock); spin_unlock(&inode_hash_lock); } @@ -1107,7 +1107,7 @@ again: */ spin_lock(&inode->i_lock); inode->i_state |= I_NEW; - hlist_add_head(&inode->i_hash, head); + hlist_add_head_rcu(&inode->i_hash, head); spin_unlock(&inode->i_lock); if (!creating) inode_sb_list_add(inode); @@ -1201,7 +1201,7 @@ again: inode->i_ino = ino; spin_lock(&inode->i_lock); inode->i_state = I_NEW; - hlist_add_head(&inode->i_hash, head); + hlist_add_head_rcu(&inode->i_hash, head); spin_unlock(&inode->i_lock); inode_sb_list_add(inode); spin_unlock(&inode_hash_lock); @@ -1244,15 +1244,10 @@ static int test_inode_iunique(struct super_block *sb, unsigned long ino) struct hlist_head *b = inode_hashtable + hash(sb, ino); struct inode *inode; - spin_lock(&inode_hash_lock); - hlist_for_each_entry(inode, b, i_hash) { - if (inode->i_ino == ino && inode->i_sb == sb) { - spin_unlock(&inode_hash_lock); + hlist_for_each_entry_rcu(inode, b, i_hash) { + if (inode->i_ino == ino && inode->i_sb == sb) return 0; - } } - spin_unlock(&inode_hash_lock); - return 1; } @@ -1281,6 +1276,7 @@ ino_t iunique(struct super_block *sb, ino_t max_reserved) static unsigned int counter; ino_t res; + rcu_read_lock(); spin_lock(&iunique_lock); do { if (counter <= max_reserved) @@ -1288,6 +1284,7 @@ ino_t iunique(struct super_block *sb, ino_t max_reserved) res = counter++; } while (!test_inode_iunique(sb, res)); spin_unlock(&iunique_lock); + rcu_read_unlock(); return res; } @@ -1456,6 +1453,84 @@ out: } EXPORT_SYMBOL(find_inode_nowait); +/** + * find_inode_rcu - find an inode in the inode cache + * @sb: Super block of file system to search + * @hashval: Key to hash + * @test: Function to test match on an inode + * @data: Data for test function + * + * Search for the inode specified by @hashval and @data in the inode cache, + * where the helper function @test will return 0 if the inode does not match + * and 1 if it does. The @test function must be responsible for taking the + * i_lock spin_lock and checking i_state for an inode being freed or being + * initialized. + * + * If successful, this will return the inode for which the @test function + * returned 1 and NULL otherwise. + * + * The @test function is not permitted to take a ref on any inode presented. + * It is also not permitted to sleep. + * + * The caller must hold the RCU read lock. + */ +struct inode *find_inode_rcu(struct super_block *sb, unsigned long hashval, + int (*test)(struct inode *, void *), void *data) +{ + struct hlist_head *head = inode_hashtable + hash(sb, hashval); + struct inode *inode; + + RCU_LOCKDEP_WARN(!rcu_read_lock_held(), + "suspicious find_inode_rcu() usage"); + + hlist_for_each_entry_rcu(inode, head, i_hash) { + if (inode->i_sb == sb && + !(READ_ONCE(inode->i_state) & (I_FREEING | I_WILL_FREE)) && + test(inode, data)) + return inode; + } + return NULL; +} +EXPORT_SYMBOL(find_inode_rcu); + +/** + * find_inode_by_rcu - Find an inode in the inode cache + * @sb: Super block of file system to search + * @ino: The inode number to match + * + * Search for the inode specified by @hashval and @data in the inode cache, + * where the helper function @test will return 0 if the inode does not match + * and 1 if it does. The @test function must be responsible for taking the + * i_lock spin_lock and checking i_state for an inode being freed or being + * initialized. + * + * If successful, this will return the inode for which the @test function + * returned 1 and NULL otherwise. + * + * The @test function is not permitted to take a ref on any inode presented. + * It is also not permitted to sleep. + * + * The caller must hold the RCU read lock. + */ +struct inode *find_inode_by_ino_rcu(struct super_block *sb, + unsigned long ino) +{ + struct hlist_head *head = inode_hashtable + hash(sb, ino); + struct inode *inode; + + RCU_LOCKDEP_WARN(!rcu_read_lock_held(), + "suspicious find_inode_by_ino_rcu() usage"); + + hlist_for_each_entry_rcu(inode, head, i_hash) { + if (inode->i_ino == ino && + inode->i_sb == sb && + !(READ_ONCE(inode->i_state) & (I_FREEING | I_WILL_FREE))) + return inode; + } + return NULL; +} +EXPORT_SYMBOL(find_inode_by_ino_rcu); + int insert_inode_locked(struct inode *inode) { struct super_block *sb = inode->i_sb; @@ -1480,7 +1555,7 @@ int insert_inode_locked(struct inode *inode) if (likely(!old)) { spin_lock(&inode->i_lock); inode->i_state |= I_NEW | I_CREATING; - hlist_add_head(&inode->i_hash, head); + hlist_add_head_rcu(&inode->i_hash, head); spin_unlock(&inode->i_lock); spin_unlock(&inode_hash_lock); return 0; @@ -1540,6 +1615,7 @@ static void iput_final(struct inode *inode) { struct super_block *sb = inode->i_sb; const struct super_operations *op = inode->i_sb->s_op; + unsigned long state; int drop; WARN_ON(inode->i_state & I_NEW); @@ -1555,16 +1631,20 @@ static void iput_final(struct inode *inode) return; } + state = inode->i_state; if (!drop) { - inode->i_state |= I_WILL_FREE; + WRITE_ONCE(inode->i_state, state | I_WILL_FREE); spin_unlock(&inode->i_lock); + write_inode_now(inode, 1); + spin_lock(&inode->i_lock); - WARN_ON(inode->i_state & I_NEW); - inode->i_state &= ~I_WILL_FREE; + state = inode->i_state; + WARN_ON(state & I_NEW); + state &= ~I_WILL_FREE; } - inode->i_state |= I_FREEING; + WRITE_ONCE(inode->i_state, state | I_FREEING); if (!list_empty(&inode->i_lru)) inode_lru_list_del(inode); spin_unlock(&inode->i_lock); diff --git a/include/linux/fs.h b/include/linux/fs.h index 45cc10cdf6dd..5f9b2bb4b44f 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -3070,6 +3070,9 @@ extern struct inode *find_inode_nowait(struct super_block *, int (*match)(struct inode *, unsigned long, void *), void *data); +extern struct inode *find_inode_rcu(struct super_block *, unsigned long, + int (*)(struct inode *, void *), void *); +extern struct inode *find_inode_by_ino_rcu(struct super_block *, unsigned long); extern int insert_inode_locked4(struct inode *, unsigned long, int (*test)(struct inode *, void *), void *); extern int insert_inode_locked(struct inode *); #ifdef CONFIG_DEBUG_LOCK_ALLOC |