diff options
Diffstat (limited to 'fs/pipe.c')
-rw-r--r-- | fs/pipe.c | 86 |
1 files changed, 41 insertions, 45 deletions
diff --git a/fs/pipe.c b/fs/pipe.c index 52c415114838..37ba29ff3158 100644 --- a/fs/pipe.c +++ b/fs/pipe.c @@ -777,36 +777,55 @@ pipe_rdwr_release(struct inode *inode, struct file *filp) static int pipe_read_open(struct inode *inode, struct file *filp) { - /* We could have perhaps used atomic_t, but this and friends - below are the only places. So it doesn't seem worthwhile. */ + int ret = -ENOENT; + mutex_lock(&inode->i_mutex); - inode->i_pipe->readers++; + + if (inode->i_pipe) { + ret = 0; + inode->i_pipe->readers++; + } + mutex_unlock(&inode->i_mutex); - return 0; + return ret; } static int pipe_write_open(struct inode *inode, struct file *filp) { + int ret = -ENOENT; + mutex_lock(&inode->i_mutex); - inode->i_pipe->writers++; + + if (inode->i_pipe) { + ret = 0; + inode->i_pipe->writers++; + } + mutex_unlock(&inode->i_mutex); - return 0; + return ret; } static int pipe_rdwr_open(struct inode *inode, struct file *filp) { + int ret = -ENOENT; + mutex_lock(&inode->i_mutex); - if (filp->f_mode & FMODE_READ) - inode->i_pipe->readers++; - if (filp->f_mode & FMODE_WRITE) - inode->i_pipe->writers++; + + if (inode->i_pipe) { + ret = 0; + if (filp->f_mode & FMODE_READ) + inode->i_pipe->readers++; + if (filp->f_mode & FMODE_WRITE) + inode->i_pipe->writers++; + } + mutex_unlock(&inode->i_mutex); - return 0; + return ret; } /* @@ -887,17 +906,6 @@ void free_pipe_info(struct inode *inode) } static struct vfsmount *pipe_mnt __read_mostly; -static int pipefs_delete_dentry(struct dentry *dentry) -{ - /* - * At creation time, we pretended this dentry was hashed - * (by clearing DCACHE_UNHASHED bit in d_flags) - * At delete time, we restore the truth : not hashed. - * (so that dput() can proceed correctly) - */ - dentry->d_flags |= DCACHE_UNHASHED; - return 0; -} /* * pipefs_dname() is called from d_path(). @@ -909,7 +917,6 @@ static char *pipefs_dname(struct dentry *dentry, char *buffer, int buflen) } static const struct dentry_operations pipefs_dentry_operations = { - .d_delete = pipefs_delete_dentry, .d_dname = pipefs_dname, }; @@ -955,7 +962,7 @@ struct file *create_write_pipe(int flags) int err; struct inode *inode; struct file *f; - struct dentry *dentry; + struct path path; struct qstr name = { .name = "" }; err = -ENFILE; @@ -964,21 +971,16 @@ struct file *create_write_pipe(int flags) goto err; err = -ENOMEM; - dentry = d_alloc(pipe_mnt->mnt_sb->s_root, &name); - if (!dentry) + path.dentry = d_alloc(pipe_mnt->mnt_sb->s_root, &name); + if (!path.dentry) goto err_inode; + path.mnt = mntget(pipe_mnt); - dentry->d_op = &pipefs_dentry_operations; - /* - * We dont want to publish this dentry into global dentry hash table. - * We pretend dentry is already hashed, by unsetting DCACHE_UNHASHED - * This permits a working /proc/$pid/fd/XXX on pipes - */ - dentry->d_flags &= ~DCACHE_UNHASHED; - d_instantiate(dentry, inode); + path.dentry->d_op = &pipefs_dentry_operations; + d_instantiate(path.dentry, inode); err = -ENFILE; - f = alloc_file(pipe_mnt, dentry, FMODE_WRITE, &write_pipefifo_fops); + f = alloc_file(&path, FMODE_WRITE, &write_pipefifo_fops); if (!f) goto err_dentry; f->f_mapping = inode->i_mapping; @@ -990,7 +992,7 @@ struct file *create_write_pipe(int flags) err_dentry: free_pipe_info(inode); - dput(dentry); + path_put(&path); return ERR_PTR(err); err_inode: @@ -1009,20 +1011,14 @@ void free_write_pipe(struct file *f) struct file *create_read_pipe(struct file *wrf, int flags) { - struct file *f = get_empty_filp(); + /* Grab pipe from the writer */ + struct file *f = alloc_file(&wrf->f_path, FMODE_READ, + &read_pipefifo_fops); if (!f) return ERR_PTR(-ENFILE); - /* Grab pipe from the writer */ - f->f_path = wrf->f_path; path_get(&wrf->f_path); - f->f_mapping = wrf->f_path.dentry->d_inode->i_mapping; - - f->f_pos = 0; f->f_flags = O_RDONLY | (flags & O_NONBLOCK); - f->f_op = &read_pipefifo_fops; - f->f_mode = FMODE_READ; - f->f_version = 0; return f; } |