1 files changed, 44 insertions, 14 deletions

diff --git a/fs/file.c b/fs/file.c
index 771578b33fb6..60a45e9f5323 100644
--- a/fs/file.c
+++ b/fs/file.c
@@ -34,7 +34,7 @@ static void *alloc_fdmem(size_t size)
          * vmalloc() if the allocation size will be considered "large" by the VM.
          */
         if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
-                void *data = kmalloc(size, GFP_KERNEL|__GFP_NOWARN);
+                void *data = kmalloc(size, GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY);
                 if (data != NULL)
                         return data;
         }
@@ -683,35 +683,65 @@ EXPORT_SYMBOL(fget_raw);
  * The fput_needed flag returned by fget_light should be passed to the
  * corresponding fput_light.
  */
-struct file *__fget_light(unsigned int fd, fmode_t mask, int *fput_needed)
+static unsigned long __fget_light(unsigned int fd, fmode_t mask)
 {
         struct files_struct *files = current->files;
         struct file *file;
 
-        *fput_needed = 0;
         if (atomic_read(&files->count) == 1) {
                 file = __fcheck_files(files, fd);
-                if (file && (file->f_mode & mask))
-                        file = NULL;
+                if (!file || unlikely(file->f_mode & mask))
+                        return 0;
+                return (unsigned long)file;
         } else {
                 file = __fget(fd, mask);
-                if (file)
-                        *fput_needed = 1;
+                if (!file)
+                        return 0;
+                return FDPUT_FPUT | (unsigned long)file;
         }
-
-        return file;
 }
-struct file *fget_light(unsigned int fd, int *fput_needed)
+unsigned long __fdget(unsigned int fd)
 {
-        return __fget_light(fd, FMODE_PATH, fput_needed);
+        return __fget_light(fd, FMODE_PATH);
 }
-EXPORT_SYMBOL(fget_light);
+EXPORT_SYMBOL(__fdget);
 
-struct file *fget_raw_light(unsigned int fd, int *fput_needed)
+unsigned long __fdget_raw(unsigned int fd)
 {
-        return __fget_light(fd, 0, fput_needed);
+        return __fget_light(fd, 0);
+}
+
+unsigned long __fdget_pos(unsigned int fd)
+{
+        struct files_struct *files = current->files;
+        struct file *file;
+        unsigned long v;
+
+        if (atomic_read(&files->count) == 1) {
+                file = __fcheck_files(files, fd);
+                v = 0;
+        } else {
+                file = __fget(fd, 0);
+                v = FDPUT_FPUT;
+        }
+        if (!file)
+                return 0;
+
+        if (file->f_mode & FMODE_ATOMIC_POS) {
+                if (file_count(file) > 1) {
+                        v |= FDPUT_POS_UNLOCK;
+                        mutex_lock(&file->f_pos_lock);
+                }
+        }
+        return v | (unsigned long)file;
 }
 
+/*
+ * We only lock f_pos if we have threads or if the file might be
+ * shared with another process. In both cases we'll have an elevated
+ * file count (done either by fdget() or by fork()).
+ */
+
 void set_close_on_exec(unsigned int fd, int flag)
 {
         struct files_struct *files = current->files;