xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Browse Source 
Pull misc vfs updates from Al Viro:
 "Assorted fixes (really no common topic here)"

* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  vfs: Make __vfs_write() static
  vfs: fix preadv64v2 and pwritev64v2 compat syscalls with offset == -1
  pipe: stop using ->can_merge
  splice: don't merge into linked buffers
  fs: move generic stat response attr handling to vfs_getattr_nosec
  orangefs: don't reinitialize result_mask in ->getattr
  fs/devpts: always delete dcache dentry-s in dput()
This commit is contained in:
Linus Torvalds
2019-03-12 13:27:20 -07:00
parent a667cb7a94 12e1e7af1a
commit 5f739e4a49
10 changed files with 52 additions and 30 deletions
Download Patch File Download Diff File Expand all files Collapse all files

32
fs/pipe.c
View File

@@ -225,8 +225,15 @@ void generic_pipe_buf_release(struct pipe_inode_info *pipe,
}
EXPORT_SYMBOL(generic_pipe_buf_release);
/* New data written to a pipe may be appended to a buffer with this type. */
static const struct pipe_buf_operations anon_pipe_buf_ops = {
.can_merge = 1,
.confirm = generic_pipe_buf_confirm,
.release = anon_pipe_buf_release,
.steal = anon_pipe_buf_steal,
.get = generic_pipe_buf_get,
};
static const struct pipe_buf_operations anon_pipe_buf_nomerge_ops = {
.confirm = generic_pipe_buf_confirm,
.release = anon_pipe_buf_release,
.steal = anon_pipe_buf_steal,
@@ -234,13 +241,32 @@ static const struct pipe_buf_operations anon_pipe_buf_ops = {
};
static const struct pipe_buf_operations packet_pipe_buf_ops = {
.can_merge = 0,
.confirm = generic_pipe_buf_confirm,
.release = anon_pipe_buf_release,
.steal = anon_pipe_buf_steal,
.get = generic_pipe_buf_get,
};
/**
* pipe_buf_mark_unmergeable - mark a &struct pipe_buffer as unmergeable
* @buf: the buffer to mark
*
* Description:
* This function ensures that no future writes will be merged into the
* given &struct pipe_buffer. This is necessary when multiple pipe buffers
* share the same backing page.
*/
void pipe_buf_mark_unmergeable(struct pipe_buffer *buf)
{
if (buf->ops == &anon_pipe_buf_ops)
buf->ops = &anon_pipe_buf_nomerge_ops;
}
static bool pipe_buf_can_merge(struct pipe_buffer *buf)
{
return buf->ops == &anon_pipe_buf_ops;
}
static ssize_t
pipe_read(struct kiocb *iocb, struct iov_iter *to)
{
@@ -378,7 +404,7 @@ pipe_write(struct kiocb *iocb, struct iov_iter *from)
struct pipe_buffer *buf = pipe->bufs + lastbuf;
int offset = buf->offset + buf->len;
if (buf->ops->can_merge && offset + chars <= PAGE_SIZE) {
if (pipe_buf_can_merge(buf) && offset + chars <= PAGE_SIZE) {
ret = pipe_buf_confirm(pipe, buf);
if (ret)
goto out;