switch simple cases of fget_light to fdget

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 30 insertions, 40 deletions

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 2bd199bfaef8..bd9c5bca42ae 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -467,14 +467,13 @@ 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;
@@ -500,7 +499,7 @@ static inline int perf_cgroup_connect(int fd, struct perf_event *event,
                 ret = -EINVAL;
         }
 out:
-        fput_light(file, fput_needed);
+        fdput(f);
         return ret;
 }
 
@@ -3233,21 +3232,18 @@ 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,
@@ -3279,22 +3275,19 @@ 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;
         }
 
@@ -6229,12 +6222,11 @@ 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... */
@@ -6269,12 +6261,10 @@ SYSCALL_DEFINE5(perf_event_open,
                 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)
@@ -6450,7 +6440,7 @@ 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;
 
@@ -6464,7 +6454,7 @@ 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;