Merge tag 'notifications-20200601' of git://git.kernel.org/pub/scm/linux/kernel/git...

[platform/kernel/linux-rpi.git] / fs / splice.c

diff --git a/fs/splice.c b/fs/splice.c
index 50f3c02..d7c8a7c 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,
@@ -139,27 +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);
 }
 
 /**
@@ -1494,7 +1473,7 @@ static int opipe_prep(struct pipe_inode_info *pipe, unsigned int flags)
         * Check pipe occupancy without the inode lock first. This function
         * is speculative anyways, so missing one is ok.
         */
-       if (pipe_full(pipe->head, pipe->tail, pipe->max_usage))
+       if (!pipe_full(pipe->head, pipe->tail, pipe->max_usage))
                return 0;
 
        ret = 0;
@@ -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;
@@ -1754,8 +1731,7 @@ static int link_pipe(struct pipe_inode_info *ipipe,
  * The 'flags' used are the SPLICE_F_* variants, currently the only
  * applicable one is SPLICE_F_NONBLOCK.
  */
-static long do_tee(struct file *in, struct file *out, size_t len,
-                  unsigned int flags)
+long do_tee(struct file *in, struct file *out, size_t len, unsigned int flags)
 {
        struct pipe_inode_info *ipipe = get_pipe_info(in, true);
        struct pipe_inode_info *opipe = get_pipe_info(out, true);