diff options
Diffstat (limited to 'fs/splice.c')
| -rw-r--r-- | fs/splice.c | 24 |
1 files changed, 11 insertions, 13 deletions
diff --git a/fs/splice.c b/fs/splice.c index a567010b62a..c1072b6940c 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -713,6 +713,7 @@ ssize_t splice_from_pipe(struct pipe_inode_info *pipe, struct file *out, { int ret, do_wakeup, err; struct splice_desc sd; + struct inode *inode = out->f_mapping->host; ret = 0; do_wakeup = 0; @@ -722,8 +723,13 @@ ssize_t splice_from_pipe(struct pipe_inode_info *pipe, struct file *out, sd.file = out; sd.pos = *ppos; - if (pipe->inode) - mutex_lock(&pipe->inode->i_mutex); + /* + * The actor worker might be calling ->prepare_write and + * ->commit_write. Most of the time, these expect i_mutex to + * be held. Since this may result in an ABBA deadlock with + * pipe->inode, we have to order lock acquiry here. + */ + inode_double_lock(inode, pipe->inode); for (;;) { if (pipe->nrbufs) { @@ -797,8 +803,7 @@ ssize_t splice_from_pipe(struct pipe_inode_info *pipe, struct file *out, pipe_wait(pipe); } - if (pipe->inode) - mutex_unlock(&pipe->inode->i_mutex); + inode_double_unlock(inode, pipe->inode); if (do_wakeup) { smp_mb(); @@ -1400,13 +1405,7 @@ static int link_pipe(struct pipe_inode_info *ipipe, * grabbing by inode address. Otherwise two different processes * could deadlock (one doing tee from A -> B, the other from B -> A). */ - if (ipipe->inode < opipe->inode) { - mutex_lock_nested(&ipipe->inode->i_mutex, I_MUTEX_PARENT); - mutex_lock_nested(&opipe->inode->i_mutex, I_MUTEX_CHILD); - } else { - mutex_lock_nested(&opipe->inode->i_mutex, I_MUTEX_PARENT); - mutex_lock_nested(&ipipe->inode->i_mutex, I_MUTEX_CHILD); - } + inode_double_lock(ipipe->inode, opipe->inode); do { if (!opipe->readers) { @@ -1450,8 +1449,7 @@ static int link_pipe(struct pipe_inode_info *ipipe, i++; } while (len); - mutex_unlock(&ipipe->inode->i_mutex); - mutex_unlock(&opipe->inode->i_mutex); + inode_double_unlock(ipipe->inode, opipe->inode); /* * If we put data in the output pipe, wakeup any potential readers. |