diff options
| author | Roland Dreier <rdreier@cisco.com> | 2009-12-18 09:41:24 -0800 |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2009-12-22 12:27:34 -0500 |
| commit | 628ff7c1d8d8466a5ad8078bd0206a130f8b8a51 (patch) | |
| tree | cc7ab0c90849be38e200fc6ff6a3a09e3caf0405 /fs | |
| parent | ed2617585f39dd12fae38c657bba68b9779ea10d (diff) | |
| download | lwn-628ff7c1d8d8466a5ad8078bd0206a130f8b8a51.tar.gz lwn-628ff7c1d8d8466a5ad8078bd0206a130f8b8a51.zip | |
anonfd: Allow making anon files read-only
It seems a couple places such as arch/ia64/kernel/perfmon.c and
drivers/infiniband/core/uverbs_main.c could use anon_inode_getfile()
instead of a private pseudo-fs + alloc_file(), if only there were a way
to get a read-only file. So provide this by having anon_inode_getfile()
create a read-only file if we pass O_RDONLY in flags.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/anon_inodes.c | 12 | ||||
| -rw-r--r-- | fs/eventfd.c | 2 | ||||
| -rw-r--r-- | fs/eventpoll.c | 2 | ||||
| -rw-r--r-- | fs/signalfd.c | 2 | ||||
| -rw-r--r-- | fs/timerfd.c | 2 |
5 files changed, 14 insertions, 6 deletions
diff --git a/fs/anon_inodes.c b/fs/anon_inodes.c index 2c994591f4d7..598237e97221 100644 --- a/fs/anon_inodes.c +++ b/fs/anon_inodes.c @@ -89,11 +89,19 @@ struct file *anon_inode_getfile(const char *name, struct qstr this; struct path path; struct file *file; + fmode_t mode; int error; if (IS_ERR(anon_inode_inode)) return ERR_PTR(-ENODEV); + switch (flags & O_ACCMODE) { + case O_RDONLY: mode = FMODE_READ; break; + case O_WRONLY: mode = FMODE_WRITE; break; + case O_RDWR: mode = FMODE_READ | FMODE_WRITE; break; + default: return ERR_PTR(-EINVAL); + } + if (fops->owner && !try_module_get(fops->owner)) return ERR_PTR(-ENOENT); @@ -121,13 +129,13 @@ struct file *anon_inode_getfile(const char *name, d_instantiate(path.dentry, anon_inode_inode); error = -ENFILE; - file = alloc_file(&path, FMODE_READ | FMODE_WRITE, fops); + file = alloc_file(&path, mode, fops); if (!file) goto err_dput; file->f_mapping = anon_inode_inode->i_mapping; file->f_pos = 0; - file->f_flags = O_RDWR | (flags & O_NONBLOCK); + file->f_flags = flags & (O_ACCMODE | O_NONBLOCK); file->f_version = 0; file->private_data = priv; diff --git a/fs/eventfd.c b/fs/eventfd.c index 8b47e4200e65..d26402ff06ea 100644 --- a/fs/eventfd.c +++ b/fs/eventfd.c @@ -339,7 +339,7 @@ struct file *eventfd_file_create(unsigned int count, int flags) ctx->flags = flags; file = anon_inode_getfile("[eventfd]", &eventfd_fops, ctx, - flags & EFD_SHARED_FCNTL_FLAGS); + O_RDWR | (flags & EFD_SHARED_FCNTL_FLAGS)); if (IS_ERR(file)) eventfd_free_ctx(ctx); diff --git a/fs/eventpoll.c b/fs/eventpoll.c index 366c503f9657..bd056a5b4efc 100644 --- a/fs/eventpoll.c +++ b/fs/eventpoll.c @@ -1206,7 +1206,7 @@ SYSCALL_DEFINE1(epoll_create1, int, flags) * a file structure and a free file descriptor. */ error = anon_inode_getfd("[eventpoll]", &eventpoll_fops, ep, - flags & O_CLOEXEC); + O_RDWR | (flags & O_CLOEXEC)); if (error < 0) ep_free(ep); diff --git a/fs/signalfd.c b/fs/signalfd.c index b07565c94386..1dabe4ee02fe 100644 --- a/fs/signalfd.c +++ b/fs/signalfd.c @@ -236,7 +236,7 @@ SYSCALL_DEFINE4(signalfd4, int, ufd, sigset_t __user *, user_mask, * anon_inode_getfd() will install the fd. */ ufd = anon_inode_getfd("[signalfd]", &signalfd_fops, ctx, - flags & (O_CLOEXEC | O_NONBLOCK)); + O_RDWR | (flags & (O_CLOEXEC | O_NONBLOCK))); if (ufd < 0) kfree(ctx); } else { diff --git a/fs/timerfd.c b/fs/timerfd.c index b042bd7034b1..1bfc95ad5f71 100644 --- a/fs/timerfd.c +++ b/fs/timerfd.c @@ -200,7 +200,7 @@ SYSCALL_DEFINE2(timerfd_create, int, clockid, int, flags) hrtimer_init(&ctx->tmr, clockid, HRTIMER_MODE_ABS); ufd = anon_inode_getfd("[timerfd]", &timerfd_fops, ctx, - flags & TFD_SHARED_FCNTL_FLAGS); + O_RDWR | (flags & TFD_SHARED_FCNTL_FLAGS)); if (ufd < 0) kfree(ctx); |