Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/fs/file.c b/fs/file.c
index 7ffd6e9..3da91a1 100644
--- a/fs/file.c
+++ b/fs/file.c
@@ -158,7 +158,7 @@
* or have finished their rcu_read_lock_sched() section.
*/
if (atomic_read(&files->count) > 1)
- synchronize_sched();
+ synchronize_rcu();
spin_lock(&files->file_lock);
if (!new_fdt)
@@ -457,6 +457,7 @@
.full_fds_bits = init_files.full_fds_bits_init,
},
.file_lock = __SPIN_LOCK_UNLOCKED(init_files.file_lock),
+ .resize_wait = __WAIT_QUEUE_HEAD_INITIALIZER(init_files.resize_wait),
};
static unsigned int find_next_fd(struct fdtable *fdt, unsigned int start)
@@ -640,6 +641,35 @@
}
EXPORT_SYMBOL(__close_fd); /* for ksys_close() */
+/*
+ * variant of __close_fd that gets a ref on the file for later fput
+ */
+int __close_fd_get_file(unsigned int fd, struct file **res)
+{
+ struct files_struct *files = current->files;
+ struct file *file;
+ struct fdtable *fdt;
+
+ spin_lock(&files->file_lock);
+ fdt = files_fdtable(files);
+ if (fd >= fdt->max_fds)
+ goto out_unlock;
+ file = fdt->fd[fd];
+ if (!file)
+ goto out_unlock;
+ rcu_assign_pointer(fdt->fd[fd], NULL);
+ __put_unused_fd(files, fd);
+ spin_unlock(&files->file_lock);
+ get_file(file);
+ *res = file;
+ return filp_close(file, files);
+
+out_unlock:
+ spin_unlock(&files->file_lock);
+ *res = NULL;
+ return -ENOENT;
+}
+
void do_close_on_exec(struct files_struct *files)
{
unsigned i;
@@ -676,7 +706,7 @@
spin_unlock(&files->file_lock);
}
-static struct file *__fget(unsigned int fd, fmode_t mask)
+static struct file *__fget(unsigned int fd, fmode_t mask, unsigned int refs)
{
struct files_struct *files = current->files;
struct file *file;
@@ -691,7 +721,7 @@
*/
if (file->f_mode & mask)
file = NULL;
- else if (!get_file_rcu(file))
+ else if (!get_file_rcu_many(file, refs))
goto loop;
}
rcu_read_unlock();
@@ -699,15 +729,20 @@
return file;
}
+struct file *fget_many(unsigned int fd, unsigned int refs)
+{
+ return __fget(fd, FMODE_PATH, refs);
+}
+
struct file *fget(unsigned int fd)
{
- return __fget(fd, FMODE_PATH);
+ return __fget(fd, FMODE_PATH, 1);
}
EXPORT_SYMBOL(fget);
struct file *fget_raw(unsigned int fd)
{
- return __fget(fd, 0);
+ return __fget(fd, 0, 1);
}
EXPORT_SYMBOL(fget_raw);
@@ -738,7 +773,7 @@
return 0;
return (unsigned long)file;
} else {
- file = __fget(fd, mask);
+ file = __fget(fd, mask, 1);
if (!file)
return 0;
return FDPUT_FPUT | (unsigned long)file;