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 <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index 3cbaec925606a492b9b52e6b59d1afe87749b10f..00c5e3acee460421e84bdb91968bfc0aebff4e5a 100644 (file)
--- 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 97eec7522bf203a929cefd7e0afd67fdd87cd7cb..7a2b2de87b1fa452e6d30eb944416b8d691aa0d2 100644 (file)
--- 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 58890897402abc339960fb152d1eb86dfeab163d..c7c4fb5f345f3ec0e49071f0657c66cf452303d6 100644 (file)
--- 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 bc834073cf743c7b7bd210dfc1fff7f6cdb6efad..2c2f45a9afc066c237c05e82792eb05624e3bc85 100644 (file)
--- 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 7c057daa09313cceb1df9b609b52d615221d1f1d..0c31b94612623d33098eb93b63230195b4914462 100644 (file)
--- 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 c5ece4c2b04d4a81b1947f72ea77cf18da9ca5eb..5c2263f3f8575d58ca256ab34fd76998950f20ea 100644 (file)
--- 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)