diff options
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/fuse/dev.c | 2 | ||||
| -rw-r--r-- | fs/pipe.c | 96 | ||||
| -rw-r--r-- | fs/splice.c | 81 |
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; |