summaryrefslogtreecommitdiffstats
path: root/fs
diff options
context:
space:
mode:
Diffstat (limited to 'fs')
-rw-r--r--fs/fuse/dev.c2
-rw-r--r--fs/pipe.c96
-rw-r--r--fs/splice.c81
3 files changed, 51 insertions, 128 deletions
diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index c7a65cf2bcca..4907e3d1f56c 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -805,7 +805,7 @@ static int fuse_try_move_page(struct fuse_copy_state *cs, struct page **pagep)
if (cs->len != PAGE_SIZE)
goto out_fallback;
- if (pipe_buf_steal(cs->pipe, buf) != 0)
+ if (!pipe_buf_try_steal(cs->pipe, buf))
goto out_fallback;
newpage = buf->page;
diff --git a/fs/pipe.c b/fs/pipe.c
index 16fb72e9abf7..c7c4fb5f345f 100644
--- a/fs/pipe.c
+++ b/fs/pipe.c
@@ -140,21 +140,20 @@ static void anon_pipe_buf_release(struct pipe_inode_info *pipe,
put_page(page);
}
-static int anon_pipe_buf_steal(struct pipe_inode_info *pipe,
- struct pipe_buffer *buf)
+static bool anon_pipe_buf_try_steal(struct pipe_inode_info *pipe,
+ struct pipe_buffer *buf)
{
struct page *page = buf->page;
- if (page_count(page) == 1) {
- memcg_kmem_uncharge_page(page, 0);
- __SetPageLocked(page);
- return 0;
- }
- return 1;
+ if (page_count(page) != 1)
+ return false;
+ memcg_kmem_uncharge_page(page, 0);
+ __SetPageLocked(page);
+ return true;
}
/**
- * generic_pipe_buf_steal - attempt to take ownership of a &pipe_buffer
+ * generic_pipe_buf_try_steal - attempt to take ownership of a &pipe_buffer
* @pipe: the pipe that the buffer belongs to
* @buf: the buffer to attempt to steal
*
@@ -165,8 +164,8 @@ static int anon_pipe_buf_steal(struct pipe_inode_info *pipe,
* he wishes; the typical use is insertion into a different file
* page cache.
*/
-int generic_pipe_buf_steal(struct pipe_inode_info *pipe,
- struct pipe_buffer *buf)
+bool generic_pipe_buf_try_steal(struct pipe_inode_info *pipe,
+ struct pipe_buffer *buf)
{
struct page *page = buf->page;
@@ -177,12 +176,11 @@ int generic_pipe_buf_steal(struct pipe_inode_info *pipe,
*/
if (page_count(page) == 1) {
lock_page(page);
- return 0;
+ return true;
}
-
- return 1;
+ return false;
}
-EXPORT_SYMBOL(generic_pipe_buf_steal);
+EXPORT_SYMBOL(generic_pipe_buf_try_steal);
/**
* generic_pipe_buf_get - get a reference to a &struct pipe_buffer
@@ -201,22 +199,6 @@ bool generic_pipe_buf_get(struct pipe_inode_info *pipe, struct pipe_buffer *buf)
EXPORT_SYMBOL(generic_pipe_buf_get);
/**
- * generic_pipe_buf_confirm - verify contents of the pipe buffer
- * @info: the pipe that the buffer belongs to
- * @buf: the buffer to confirm
- *
- * Description:
- * This function does nothing, because the generic pipe code uses
- * pages that are always good when inserted into the pipe.
- */
-int generic_pipe_buf_confirm(struct pipe_inode_info *info,
- struct pipe_buffer *buf)
-{
- return 0;
-}
-EXPORT_SYMBOL(generic_pipe_buf_confirm);
-
-/**
* generic_pipe_buf_release - put a reference to a &struct pipe_buffer
* @pipe: the pipe that the buffer belongs to
* @buf: the buffer to put a reference to
@@ -231,48 +213,12 @@ 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 = {
- .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,
- .get = generic_pipe_buf_get,
-};
-
-static const struct pipe_buf_operations packet_pipe_buf_ops = {
- .confirm = generic_pipe_buf_confirm,
- .release = anon_pipe_buf_release,
- .steal = anon_pipe_buf_steal,
- .get = generic_pipe_buf_get,
+ .release = anon_pipe_buf_release,
+ .try_steal = anon_pipe_buf_try_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;
-}
-
/* Done while waiting without holding the pipe lock - thus the READ_ONCE() */
static inline bool pipe_readable(const struct pipe_inode_info *pipe)
{
@@ -478,7 +424,8 @@ pipe_write(struct kiocb *iocb, struct iov_iter *from)
struct pipe_buffer *buf = &pipe->bufs[(head - 1) & mask];
int offset = buf->offset + buf->len;
- if (pipe_buf_can_merge(buf) && offset + chars <= PAGE_SIZE) {
+ if ((buf->flags & PIPE_BUF_FLAG_CAN_MERGE) &&
+ offset + chars <= PAGE_SIZE) {
ret = pipe_buf_confirm(pipe, buf);
if (ret)
goto out;
@@ -541,11 +488,10 @@ pipe_write(struct kiocb *iocb, struct iov_iter *from)
buf->ops = &anon_pipe_buf_ops;
buf->offset = 0;
buf->len = 0;
- buf->flags = 0;
- if (is_packetized(filp)) {
- buf->ops = &packet_pipe_buf_ops;
+ if (is_packetized(filp))
buf->flags = PIPE_BUF_FLAG_PACKET;
- }
+ else
+ buf->flags = PIPE_BUF_FLAG_CAN_MERGE;
pipe->tmp_page = NULL;
copied = copy_page_from_iter(page, 0, PAGE_SIZE, from);
diff --git a/fs/splice.c b/fs/splice.c
index 5013565eb756..6b3c9a018a8e 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -44,8 +44,8 @@
* addition of remove_mapping(). If success is returned, the caller may
* attempt to reuse this page for another destination.
*/
-static int page_cache_pipe_buf_steal(struct pipe_inode_info *pipe,
- struct pipe_buffer *buf)
+static bool page_cache_pipe_buf_try_steal(struct pipe_inode_info *pipe,
+ struct pipe_buffer *buf)
{
struct page *page = buf->page;
struct address_space *mapping;
@@ -76,7 +76,7 @@ static int page_cache_pipe_buf_steal(struct pipe_inode_info *pipe,
*/
if (remove_mapping(mapping, page)) {
buf->flags |= PIPE_BUF_FLAG_LRU;
- return 0;
+ return true;
}
}
@@ -86,7 +86,7 @@ static int page_cache_pipe_buf_steal(struct pipe_inode_info *pipe,
*/
out_unlock:
unlock_page(page);
- return 1;
+ return false;
}
static void page_cache_pipe_buf_release(struct pipe_inode_info *pipe,
@@ -139,27 +139,26 @@ error:
}
const struct pipe_buf_operations page_cache_pipe_buf_ops = {
- .confirm = page_cache_pipe_buf_confirm,
- .release = page_cache_pipe_buf_release,
- .steal = page_cache_pipe_buf_steal,
- .get = generic_pipe_buf_get,
+ .confirm = page_cache_pipe_buf_confirm,
+ .release = page_cache_pipe_buf_release,
+ .try_steal = page_cache_pipe_buf_try_steal,
+ .get = generic_pipe_buf_get,
};
-static int user_page_pipe_buf_steal(struct pipe_inode_info *pipe,
- struct pipe_buffer *buf)
+static bool user_page_pipe_buf_try_steal(struct pipe_inode_info *pipe,
+ struct pipe_buffer *buf)
{
if (!(buf->flags & PIPE_BUF_FLAG_GIFT))
- return 1;
+ return false;
buf->flags |= PIPE_BUF_FLAG_LRU;
- return generic_pipe_buf_steal(pipe, buf);
+ return generic_pipe_buf_try_steal(pipe, buf);
}
static const struct pipe_buf_operations user_page_pipe_buf_ops = {
- .confirm = generic_pipe_buf_confirm,
- .release = page_cache_pipe_buf_release,
- .steal = user_page_pipe_buf_steal,
- .get = generic_pipe_buf_get,
+ .release = page_cache_pipe_buf_release,
+ .try_steal = user_page_pipe_buf_try_steal,
+ .get = generic_pipe_buf_get,
};
static void wakeup_pipe_readers(struct pipe_inode_info *pipe)
@@ -331,24 +330,15 @@ ssize_t generic_file_splice_read(struct file *in, loff_t *ppos,
EXPORT_SYMBOL(generic_file_splice_read);
const struct pipe_buf_operations default_pipe_buf_ops = {
- .confirm = generic_pipe_buf_confirm,
- .release = generic_pipe_buf_release,
- .steal = generic_pipe_buf_steal,
- .get = generic_pipe_buf_get,
+ .release = generic_pipe_buf_release,
+ .try_steal = generic_pipe_buf_try_steal,
+ .get = generic_pipe_buf_get,
};
-int generic_pipe_buf_nosteal(struct pipe_inode_info *pipe,
- struct pipe_buffer *buf)
-{
- return 1;
-}
-
/* Pipe buffer operations for a socket and similar. */
const struct pipe_buf_operations nosteal_pipe_buf_ops = {
- .confirm = generic_pipe_buf_confirm,
- .release = generic_pipe_buf_release,
- .steal = generic_pipe_buf_nosteal,
- .get = generic_pipe_buf_get,
+ .release = generic_pipe_buf_release,
+ .get = generic_pipe_buf_get,
};
EXPORT_SYMBOL(nosteal_pipe_buf_ops);
@@ -852,15 +842,9 @@ EXPORT_SYMBOL(generic_splice_sendpage);
static long do_splice_from(struct pipe_inode_info *pipe, struct file *out,
loff_t *ppos, size_t len, unsigned int flags)
{
- ssize_t (*splice_write)(struct pipe_inode_info *, struct file *,
- loff_t *, size_t, unsigned int);
-
if (out->f_op->splice_write)
- splice_write = out->f_op->splice_write;
- else
- splice_write = default_file_splice_write;
-
- return splice_write(pipe, out, ppos, len, flags);
+ return out->f_op->splice_write(pipe, out, ppos, len, flags);
+ return default_file_splice_write(pipe, out, ppos, len, flags);
}
/*
@@ -870,8 +854,6 @@ static long do_splice_to(struct file *in, loff_t *ppos,
struct pipe_inode_info *pipe, size_t len,
unsigned int flags)
{
- ssize_t (*splice_read)(struct file *, loff_t *,
- struct pipe_inode_info *, size_t, unsigned int);
int ret;
if (unlikely(!(in->f_mode & FMODE_READ)))
@@ -885,11 +867,8 @@ static long do_splice_to(struct file *in, loff_t *ppos,
len = MAX_RW_COUNT;
if (in->f_op->splice_read)
- splice_read = in->f_op->splice_read;
- else
- splice_read = default_file_splice_read;
-
- return splice_read(in, ppos, pipe, len, flags);
+ return in->f_op->splice_read(in, ppos, pipe, len, flags);
+ return default_file_splice_read(in, ppos, pipe, len, flags);
}
/**
@@ -1626,12 +1605,11 @@ retry:
*obuf = *ibuf;
/*
- * Don't inherit the gift flag, we need to
+ * Don't inherit the gift and merge flags, we need to
* prevent multiple steals of this page.
*/
obuf->flags &= ~PIPE_BUF_FLAG_GIFT;
-
- pipe_buf_mark_unmergeable(obuf);
+ obuf->flags &= ~PIPE_BUF_FLAG_CAN_MERGE;
obuf->len = len;
ibuf->offset += len;
@@ -1719,12 +1697,11 @@ static int link_pipe(struct pipe_inode_info *ipipe,
*obuf = *ibuf;
/*
- * Don't inherit the gift flag, we need to
- * prevent multiple steals of this page.
+ * Don't inherit the gift and merge flag, we need to prevent
+ * multiple steals of this page.
*/
obuf->flags &= ~PIPE_BUF_FLAG_GIFT;
-
- pipe_buf_mark_unmergeable(obuf);
+ obuf->flags &= ~PIPE_BUF_FLAG_CAN_MERGE;
if (obuf->len > len)
obuf->len = len;
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-16 14:57:15 +0000