From c928f642c29a5ffb02e16f2430b42b876dde69de Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 20 May 2020 17:58:16 +0200 Subject: fs: rename pipe_buf ->steal to ->try_steal And replace the arcane return value convention with a simple bool where true means success and false means failure. [AV: braino fix folded in] Signed-off-by: Christoph Hellwig Signed-off-by: Al Viro --- drivers/char/virtio_console.c | 2 +- fs/fuse/dev.c | 2 +- fs/pipe.c | 34 ++++++++++++++++------------------ fs/splice.c | 40 ++++++++++++++++++++-------------------- include/linux/pipe_fs_i.h | 34 +++++++++++++++++----------------- kernel/relay.c | 6 +++--- 6 files changed, 58 insertions(+), 60 deletions(-) diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c index 3cbaec925606..00c5e3acee46 100644 --- a/drivers/char/virtio_console.c +++ b/drivers/char/virtio_console.c @@ -871,7 +871,7 @@ static int pipe_to_sg(struct pipe_inode_info *pipe, struct pipe_buffer *buf, return 0; /* Try lock this page */ - if (pipe_buf_steal(pipe, buf) == 0) { + if (pipe_buf_try_steal(pipe, buf)) { /* Get reference and unlock page for moving */ get_page(buf->page); unlock_page(buf->page); diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c index 97eec7522bf2..7a2b2de87b1f 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 58890897402a..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 @@ -216,9 +214,9 @@ void generic_pipe_buf_release(struct pipe_inode_info *pipe, EXPORT_SYMBOL(generic_pipe_buf_release); static const struct pipe_buf_operations anon_pipe_buf_ops = { - .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, }; /* Done while waiting without holding the pipe lock - thus the READ_ONCE() */ diff --git a/fs/splice.c b/fs/splice.c index bc834073cf74..2c2f45a9afc0 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, @@ -139,26 +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 = { - .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) @@ -330,15 +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 = { - .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, }; /* Pipe buffer operations for a socket and similar. */ const struct pipe_buf_operations nosteal_pipe_buf_ops = { - .release = generic_pipe_buf_release, - .get = generic_pipe_buf_get, + .release = generic_pipe_buf_release, + .get = generic_pipe_buf_get, }; EXPORT_SYMBOL(nosteal_pipe_buf_ops); diff --git a/include/linux/pipe_fs_i.h b/include/linux/pipe_fs_i.h index 7c057daa0931..0c31b9461262 100644 --- a/include/linux/pipe_fs_i.h +++ b/include/linux/pipe_fs_i.h @@ -70,11 +70,11 @@ struct pipe_inode_info { * Note on the nesting of these functions: * * ->confirm() - * ->steal() + * ->try_steal() * - * That is, ->steal() must be called on a confirmed buffer. - * See below for the meaning of each operation. Also see kerneldoc - * in fs/pipe.c for the pipe and generic variants of these hooks. + * That is, ->try_steal() must be called on a confirmed buffer. See below for + * the meaning of each operation. Also see the kerneldoc in fs/pipe.c for the + * pipe and generic variants of these hooks. */ struct pipe_buf_operations { /* @@ -94,13 +94,13 @@ struct pipe_buf_operations { /* * Attempt to take ownership of the pipe buffer and its contents. - * ->steal() returns 0 for success, in which case the contents - * of the pipe (the buf->page) is locked and now completely owned - * by the caller. The page may then be transferred to a different - * mapping, the most often used case is insertion into different - * file address space cache. + * ->try_steal() returns %true for success, in which case the contents + * of the pipe (the buf->page) is locked and now completely owned by the + * caller. The page may then be transferred to a different mapping, the + * most often used case is insertion into different file address space + * cache. */ - int (*steal)(struct pipe_inode_info *, struct pipe_buffer *); + bool (*try_steal)(struct pipe_inode_info *, struct pipe_buffer *); /* * Get a reference to the pipe buffer. @@ -201,16 +201,16 @@ static inline int pipe_buf_confirm(struct pipe_inode_info *pipe, } /** - * pipe_buf_steal - attempt to take ownership of a pipe_buffer + * 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 */ -static inline int pipe_buf_steal(struct pipe_inode_info *pipe, - struct pipe_buffer *buf) +static inline bool pipe_buf_try_steal(struct pipe_inode_info *pipe, + struct pipe_buffer *buf) { - if (!buf->ops->steal) - return 1; - return buf->ops->steal(pipe, buf); + if (!buf->ops->try_steal) + return false; + return buf->ops->try_steal(pipe, buf); } /* Differs from PIPE_BUF in that PIPE_SIZE is the length of the actual @@ -234,7 +234,7 @@ void free_pipe_info(struct pipe_inode_info *); /* Generic pipe buffer ops functions */ bool generic_pipe_buf_get(struct pipe_inode_info *, struct pipe_buffer *); -int generic_pipe_buf_steal(struct pipe_inode_info *, struct pipe_buffer *); +bool generic_pipe_buf_try_steal(struct pipe_inode_info *, struct pipe_buffer *); void generic_pipe_buf_release(struct pipe_inode_info *, struct pipe_buffer *); extern const struct pipe_buf_operations nosteal_pipe_buf_ops; diff --git a/kernel/relay.c b/kernel/relay.c index c5ece4c2b04d..5c2263f3f857 100644 --- a/kernel/relay.c +++ b/kernel/relay.c @@ -1177,9 +1177,9 @@ static void relay_pipe_buf_release(struct pipe_inode_info *pipe, } static const struct pipe_buf_operations relay_pipe_buf_ops = { - .release = relay_pipe_buf_release, - .steal = generic_pipe_buf_steal, - .get = generic_pipe_buf_get, + .release = relay_pipe_buf_release, + .try_steal = generic_pipe_buf_try_steal, + .get = generic_pipe_buf_get, }; static void relay_page_release(struct splice_pipe_desc *spd, unsigned int i) -- cgit v1.2.3-58-ga151