From f6dd975583bd8ce088400648fd9819e4691c8958 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 20 May 2020 17:58:12 +0200 Subject: pipe: merge anon_pipe_buf*_ops All the op vectors are exactly the same, they are just used to encode packet or nomerge behavior. There already is a flag for the packet behavior, so just add a new one to allow for merging. Inverting it vs the previous nomerge special casing actually allows for much nicer code. Signed-off-by: Christoph Hellwig Signed-off-by: Al Viro --- include/linux/pipe_fs_i.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/pipe_fs_i.h b/include/linux/pipe_fs_i.h index ae58fad7f1e0..3f7b07b38824 100644 --- a/include/linux/pipe_fs_i.h +++ b/include/linux/pipe_fs_i.h @@ -8,6 +8,7 @@ #define PIPE_BUF_FLAG_ATOMIC 0x02 /* was atomically mapped */ #define PIPE_BUF_FLAG_GIFT 0x04 /* page is a gift */ #define PIPE_BUF_FLAG_PACKET 0x08 /* read() as a packet */ +#define PIPE_BUF_FLAG_CAN_MERGE 0x10 /* can merge buffers */ /** * struct pipe_buffer - a linux kernel pipe buffer @@ -233,7 +234,6 @@ int generic_pipe_buf_confirm(struct pipe_inode_info *, struct pipe_buffer *); int generic_pipe_buf_steal(struct pipe_inode_info *, struct pipe_buffer *); int generic_pipe_buf_nosteal(struct pipe_inode_info *, struct pipe_buffer *); void generic_pipe_buf_release(struct pipe_inode_info *, struct pipe_buffer *); -void pipe_buf_mark_unmergeable(struct pipe_buffer *buf); extern const struct pipe_buf_operations nosteal_pipe_buf_ops; -- cgit v1.2.3 From 76887c256744740d6121af9bc4aa787712a1f694 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 20 May 2020 17:58:14 +0200 Subject: fs: make the pipe_buf_operations ->steal operation optional Just return 1 for failure if it is not present. Signed-off-by: Christoph Hellwig Signed-off-by: Al Viro --- include/linux/pipe_fs_i.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/pipe_fs_i.h b/include/linux/pipe_fs_i.h index 3f7b07b38824..e022b2459301 100644 --- a/include/linux/pipe_fs_i.h +++ b/include/linux/pipe_fs_i.h @@ -206,6 +206,8 @@ static inline int pipe_buf_confirm(struct pipe_inode_info *pipe, static inline int pipe_buf_steal(struct pipe_inode_info *pipe, struct pipe_buffer *buf) { + if (!buf->ops->steal) + return 1; return buf->ops->steal(pipe, buf); } @@ -232,7 +234,6 @@ void free_pipe_info(struct pipe_inode_info *); bool generic_pipe_buf_get(struct pipe_inode_info *, struct pipe_buffer *); int generic_pipe_buf_confirm(struct pipe_inode_info *, struct pipe_buffer *); int generic_pipe_buf_steal(struct pipe_inode_info *, struct pipe_buffer *); -int generic_pipe_buf_nosteal(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; -- cgit v1.2.3 From b8d9e7f2411b0744df2ec33e80d7698180fef21a Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 20 May 2020 17:58:15 +0200 Subject: fs: make the pipe_buf_operations ->confirm operation optional Just return 0 for success if it is not present. Signed-off-by: Christoph Hellwig Signed-off-by: Al Viro --- include/linux/pipe_fs_i.h | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'include') diff --git a/include/linux/pipe_fs_i.h b/include/linux/pipe_fs_i.h index e022b2459301..7c057daa0931 100644 --- a/include/linux/pipe_fs_i.h +++ b/include/linux/pipe_fs_i.h @@ -82,7 +82,7 @@ struct pipe_buf_operations { * and that the contents are good. If the pages in the pipe belong * to a file system, we may need to wait for IO completion in this * hook. Returns 0 for good, or a negative error value in case of - * error. + * error. If not present all pages are considered good. */ int (*confirm)(struct pipe_inode_info *, struct pipe_buffer *); @@ -195,6 +195,8 @@ static inline void pipe_buf_release(struct pipe_inode_info *pipe, static inline int pipe_buf_confirm(struct pipe_inode_info *pipe, struct pipe_buffer *buf) { + if (!buf->ops->confirm) + return 0; return buf->ops->confirm(pipe, buf); } @@ -232,7 +234,6 @@ 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_confirm(struct pipe_inode_info *, struct pipe_buffer *); int generic_pipe_buf_steal(struct pipe_inode_info *, struct pipe_buffer *); void generic_pipe_buf_release(struct pipe_inode_info *, struct pipe_buffer *); -- cgit v1.2.3 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 --- include/linux/pipe_fs_i.h | 34 +++++++++++++++++----------------- 1 file changed, 17 insertions(+), 17 deletions(-) (limited to 'include') 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; -- cgit v1.2.3