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authorLinus Torvalds <torvalds@linux-foundation.org>2012-10-02 20:25:04 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2012-10-02 20:25:04 -0700
commitaab174f0df5d72d31caccf281af5f614fa254578 (patch)
tree2a172c5009c4ac8755e858593154c258ce7709a0 /kernel
parentca41cc96b2813221b05af57d0355157924de5a07 (diff)
parent2bd2c1941f141ad780135ccc1cd08ca71a24f10a (diff)
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs update from Al Viro: - big one - consolidation of descriptor-related logics; almost all of that is moved to fs/file.c (BTW, I'm seriously tempted to rename the result to fd.c. As it is, we have a situation when file_table.c is about handling of struct file and file.c is about handling of descriptor tables; the reasons are historical - file_table.c used to be about a static array of struct file we used to have way back). A lot of stray ends got cleaned up and converted to saner primitives, disgusting mess in android/binder.c is still disgusting, but at least doesn't poke so much in descriptor table guts anymore. A bunch of relatively minor races got fixed in process, plus an ext4 struct file leak. - related thing - fget_light() partially unuglified; see fdget() in there (and yes, it generates the code as good as we used to have). - also related - bits of Cyrill's procfs stuff that got entangled into that work; _not_ all of it, just the initial move to fs/proc/fd.c and switch of fdinfo to seq_file. - Alex's fs/coredump.c spiltoff - the same story, had been easier to take that commit than mess with conflicts. The rest is a separate pile, this was just a mechanical code movement. - a few misc patches all over the place. Not all for this cycle, there'll be more (and quite a few currently sit in akpm's tree)." Fix up trivial conflicts in the android binder driver, and some fairly simple conflicts due to two different changes to the sock_alloc_file() interface ("take descriptor handling from sock_alloc_file() to callers" vs "net: Providing protocol type via system.sockprotoname xattr of /proc/PID/fd entries" adding a dentry name to the socket) * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (72 commits) MAX_LFS_FILESIZE should be a loff_t compat: fs: Generic compat_sys_sendfile implementation fs: push rcu_barrier() from deactivate_locked_super() to filesystems btrfs: reada_extent doesn't need kref for refcount coredump: move core dump functionality into its own file coredump: prevent double-free on an error path in core dumper usb/gadget: fix misannotations fcntl: fix misannotations ceph: don't abuse d_delete() on failure exits hypfs: ->d_parent is never NULL or negative vfs: delete surplus inode NULL check switch simple cases of fget_light to fdget new helpers: fdget()/fdput() switch o2hb_region_dev_write() to fget_light() proc_map_files_readdir(): don't bother with grabbing files make get_file() return its argument vhost_set_vring(): turn pollstart/pollstop into bool switch prctl_set_mm_exe_file() to fget_light() switch xfs_find_handle() to fget_light() switch xfs_swapext() to fget_light() ...
Diffstat (limited to 'kernel')
-rw-r--r--kernel/events/core.c72
-rw-r--r--kernel/exit.c97
-rw-r--r--kernel/sys.c14
-rw-r--r--kernel/taskstats.c11
4 files changed, 44 insertions, 150 deletions
diff --git a/kernel/events/core.c b/kernel/events/core.c
index deec4e50eb3..f16f3c58f11 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -468,14 +468,13 @@ static inline int perf_cgroup_connect(int fd, struct perf_event *event,
{
struct perf_cgroup *cgrp;
struct cgroup_subsys_state *css;
- struct file *file;
- int ret = 0, fput_needed;
+ struct fd f = fdget(fd);
+ int ret = 0;
- file = fget_light(fd, &fput_needed);
- if (!file)
+ if (!f.file)
return -EBADF;
- css = cgroup_css_from_dir(file, perf_subsys_id);
+ css = cgroup_css_from_dir(f.file, perf_subsys_id);
if (IS_ERR(css)) {
ret = PTR_ERR(css);
goto out;
@@ -501,7 +500,7 @@ static inline int perf_cgroup_connect(int fd, struct perf_event *event,
ret = -EINVAL;
}
out:
- fput_light(file, fput_needed);
+ fdput(f);
return ret;
}
@@ -3234,21 +3233,18 @@ unlock:
static const struct file_operations perf_fops;
-static struct file *perf_fget_light(int fd, int *fput_needed)
+static inline int perf_fget_light(int fd, struct fd *p)
{
- struct file *file;
-
- file = fget_light(fd, fput_needed);
- if (!file)
- return ERR_PTR(-EBADF);
+ struct fd f = fdget(fd);
+ if (!f.file)
+ return -EBADF;
- if (file->f_op != &perf_fops) {
- fput_light(file, *fput_needed);
- *fput_needed = 0;
- return ERR_PTR(-EBADF);
+ if (f.file->f_op != &perf_fops) {
+ fdput(f);
+ return -EBADF;
}
-
- return file;
+ *p = f;
+ return 0;
}
static int perf_event_set_output(struct perf_event *event,
@@ -3280,22 +3276,19 @@ static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
case PERF_EVENT_IOC_SET_OUTPUT:
{
- struct file *output_file = NULL;
- struct perf_event *output_event = NULL;
- int fput_needed = 0;
int ret;
-
if (arg != -1) {
- output_file = perf_fget_light(arg, &fput_needed);
- if (IS_ERR(output_file))
- return PTR_ERR(output_file);
- output_event = output_file->private_data;
+ struct perf_event *output_event;
+ struct fd output;
+ ret = perf_fget_light(arg, &output);
+ if (ret)
+ return ret;
+ output_event = output.file->private_data;
+ ret = perf_event_set_output(event, output_event);
+ fdput(output);
+ } else {
+ ret = perf_event_set_output(event, NULL);
}
-
- ret = perf_event_set_output(event, output_event);
- if (output_event)
- fput_light(output_file, fput_needed);
-
return ret;
}
@@ -6443,12 +6436,11 @@ SYSCALL_DEFINE5(perf_event_open,
struct perf_event_attr attr;
struct perf_event_context *ctx;
struct file *event_file = NULL;
- struct file *group_file = NULL;
+ struct fd group = {NULL, 0};
struct task_struct *task = NULL;
struct pmu *pmu;
int event_fd;
int move_group = 0;
- int fput_needed = 0;
int err;
/* for future expandability... */
@@ -6478,17 +6470,15 @@ SYSCALL_DEFINE5(perf_event_open,
if ((flags & PERF_FLAG_PID_CGROUP) && (pid == -1 || cpu == -1))
return -EINVAL;
- event_fd = get_unused_fd_flags(O_RDWR);
+ event_fd = get_unused_fd();
if (event_fd < 0)
return event_fd;
if (group_fd != -1) {
- group_file = perf_fget_light(group_fd, &fput_needed);
- if (IS_ERR(group_file)) {
- err = PTR_ERR(group_file);
+ err = perf_fget_light(group_fd, &group);
+ if (err)
goto err_fd;
- }
- group_leader = group_file->private_data;
+ group_leader = group.file->private_data;
if (flags & PERF_FLAG_FD_OUTPUT)
output_event = group_leader;
if (flags & PERF_FLAG_FD_NO_GROUP)
@@ -6664,7 +6654,7 @@ SYSCALL_DEFINE5(perf_event_open,
* of the group leader will find the pointer to itself in
* perf_group_detach().
*/
- fput_light(group_file, fput_needed);
+ fdput(group);
fd_install(event_fd, event_file);
return event_fd;
@@ -6678,7 +6668,7 @@ err_task:
if (task)
put_task_struct(task);
err_group_fd:
- fput_light(group_file, fput_needed);
+ fdput(group);
err_fd:
put_unused_fd(event_fd);
return err;
diff --git a/kernel/exit.c b/kernel/exit.c
index 42f25952edd..346616c0092 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -457,108 +457,13 @@ void daemonize(const char *name, ...)
/* Become as one with the init task */
daemonize_fs_struct();
- exit_files(current);
- current->files = init_task.files;
- atomic_inc(&current->files->count);
+ daemonize_descriptors();
reparent_to_kthreadd();
}
EXPORT_SYMBOL(daemonize);
-static void close_files(struct files_struct * files)
-{
- int i, j;
- struct fdtable *fdt;
-
- j = 0;
-
- /*
- * It is safe to dereference the fd table without RCU or
- * ->file_lock because this is the last reference to the
- * files structure. But use RCU to shut RCU-lockdep up.
- */
- rcu_read_lock();
- fdt = files_fdtable(files);
- rcu_read_unlock();
- for (;;) {
- unsigned long set;
- i = j * BITS_PER_LONG;
- if (i >= fdt->max_fds)
- break;
- set = fdt->open_fds[j++];
- while (set) {
- if (set & 1) {
- struct file * file = xchg(&fdt->fd[i], NULL);
- if (file) {
- filp_close(file, files);
- cond_resched();
- }
- }
- i++;
- set >>= 1;
- }
- }
-}
-
-struct files_struct *get_files_struct(struct task_struct *task)
-{
- struct files_struct *files;
-
- task_lock(task);
- files = task->files;
- if (files)
- atomic_inc(&files->count);
- task_unlock(task);
-
- return files;
-}
-
-void put_files_struct(struct files_struct *files)
-{
- struct fdtable *fdt;
-
- if (atomic_dec_and_test(&files->count)) {
- close_files(files);
- /*
- * Free the fd and fdset arrays if we expanded them.
- * If the fdtable was embedded, pass files for freeing
- * at the end of the RCU grace period. Otherwise,
- * you can free files immediately.
- */
- rcu_read_lock();
- fdt = files_fdtable(files);
- if (fdt != &files->fdtab)
- kmem_cache_free(files_cachep, files);
- free_fdtable(fdt);
- rcu_read_unlock();
- }
-}
-
-void reset_files_struct(struct files_struct *files)
-{
- struct task_struct *tsk = current;
- struct files_struct *old;
-
- old = tsk->files;
- task_lock(tsk);
- tsk->files = files;
- task_unlock(tsk);
- put_files_struct(old);
-}
-
-void exit_files(struct task_struct *tsk)
-{
- struct files_struct * files = tsk->files;
-
- if (files) {
- task_lock(tsk);
- tsk->files = NULL;
- task_unlock(tsk);
- put_files_struct(files);
- }
-}
-
#ifdef CONFIG_MM_OWNER
/*
* A task is exiting. If it owned this mm, find a new owner for the mm.
diff --git a/kernel/sys.c b/kernel/sys.c
index 241507f23ec..f9492284e5d 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -1788,15 +1788,15 @@ SYSCALL_DEFINE1(umask, int, mask)
#ifdef CONFIG_CHECKPOINT_RESTORE
static int prctl_set_mm_exe_file(struct mm_struct *mm, unsigned int fd)
{
- struct file *exe_file;
+ struct fd exe;
struct dentry *dentry;
int err;
- exe_file = fget(fd);
- if (!exe_file)
+ exe = fdget(fd);
+ if (!exe.file)
return -EBADF;
- dentry = exe_file->f_path.dentry;
+ dentry = exe.file->f_path.dentry;
/*
* Because the original mm->exe_file points to executable file, make
@@ -1805,7 +1805,7 @@ static int prctl_set_mm_exe_file(struct mm_struct *mm, unsigned int fd)
*/
err = -EACCES;
if (!S_ISREG(dentry->d_inode->i_mode) ||
- exe_file->f_path.mnt->mnt_flags & MNT_NOEXEC)
+ exe.file->f_path.mnt->mnt_flags & MNT_NOEXEC)
goto exit;
err = inode_permission(dentry->d_inode, MAY_EXEC);
@@ -1839,12 +1839,12 @@ static int prctl_set_mm_exe_file(struct mm_struct *mm, unsigned int fd)
goto exit_unlock;
err = 0;
- set_mm_exe_file(mm, exe_file);
+ set_mm_exe_file(mm, exe.file); /* this grabs a reference to exe.file */
exit_unlock:
up_write(&mm->mmap_sem);
exit:
- fput(exe_file);
+ fdput(exe);
return err;
}
diff --git a/kernel/taskstats.c b/kernel/taskstats.c
index 5eab1f3edfa..610f0838d55 100644
--- a/kernel/taskstats.c
+++ b/kernel/taskstats.c
@@ -424,16 +424,15 @@ static int cgroupstats_user_cmd(struct sk_buff *skb, struct genl_info *info)
struct nlattr *na;
size_t size;
u32 fd;
- struct file *file;
- int fput_needed;
+ struct fd f;
na = info->attrs[CGROUPSTATS_CMD_ATTR_FD];
if (!na)
return -EINVAL;
fd = nla_get_u32(info->attrs[CGROUPSTATS_CMD_ATTR_FD]);
- file = fget_light(fd, &fput_needed);
- if (!file)
+ f = fdget(fd);
+ if (!f.file)
return 0;
size = nla_total_size(sizeof(struct cgroupstats));
@@ -453,7 +452,7 @@ static int cgroupstats_user_cmd(struct sk_buff *skb, struct genl_info *info)
stats = nla_data(na);
memset(stats, 0, sizeof(*stats));
- rc = cgroupstats_build(stats, file->f_dentry);
+ rc = cgroupstats_build(stats, f.file->f_dentry);
if (rc < 0) {
nlmsg_free(rep_skb);
goto err;
@@ -462,7 +461,7 @@ static int cgroupstats_user_cmd(struct sk_buff *skb, struct genl_info *info)
rc = send_reply(rep_skb, info);
err:
- fput_light(file, fput_needed);
+ fdput(f);
return rc;
}