diff options
Diffstat (limited to 'fs/splice.c')
| -rw-r--r-- | fs/splice.c | 64 |
1 files changed, 48 insertions, 16 deletions
diff --git a/fs/splice.c b/fs/splice.c index a555d0a..07f4d86 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -22,7 +22,10 @@ #include <linux/pipe_fs_i.h> #include <linux/mm_inline.h> #include <linux/swap.h> +#include <linux/writeback.h> +#include <linux/buffer_head.h> #include <linux/module.h> +#include <linux/syscalls.h> /* * Passed to the actors @@ -38,11 +41,15 @@ static int page_cache_pipe_buf_steal(struct pipe_inode_info *info, struct pipe_buffer *buf) { struct page *page = buf->page; + struct address_space *mapping = page_mapping(page); WARN_ON(!PageLocked(page)); WARN_ON(!PageUptodate(page)); - if (!remove_mapping(page_mapping(page), page)) + if (PagePrivate(page)) + try_to_release_page(page, mapping_gfp_mask(mapping)); + + if (!remove_mapping(mapping, page)) return 1; if (PageLRU(page)) { @@ -55,7 +62,6 @@ static int page_cache_pipe_buf_steal(struct pipe_inode_info *info, spin_unlock_irq(&zone->lru_lock); } - buf->stolen = 1; return 0; } @@ -64,7 +70,6 @@ static void page_cache_pipe_buf_release(struct pipe_inode_info *info, { page_cache_release(buf->page); buf->page = NULL; - buf->stolen = 0; } static void *page_cache_pipe_buf_map(struct file *file, @@ -91,8 +96,7 @@ static void *page_cache_pipe_buf_map(struct file *file, static void page_cache_pipe_buf_unmap(struct pipe_inode_info *info, struct pipe_buffer *buf) { - if (!buf->stolen) - unlock_page(buf->page); + unlock_page(buf->page); kunmap(buf->page); } @@ -319,7 +323,8 @@ ssize_t generic_file_splice_read(struct file *in, struct inode *pipe, } /* - * Send 'len' bytes to socket from 'file' at position 'pos' using sendpage(). + * Send 'sd->len' bytes to socket from 'sd->file' at position 'sd->pos' + * using sendpage(). */ static int pipe_to_sendpage(struct pipe_inode_info *info, struct pipe_buffer *buf, struct splice_desc *sd) @@ -379,7 +384,7 @@ static int pipe_to_file(struct pipe_inode_info *info, struct pipe_buffer *buf, struct page *page; pgoff_t index; char *src; - int ret; + int ret, stolen; /* * after this, page will be locked and unmapped @@ -390,6 +395,7 @@ static int pipe_to_file(struct pipe_inode_info *info, struct pipe_buffer *buf, index = sd->pos >> PAGE_CACHE_SHIFT; offset = sd->pos & ~PAGE_CACHE_MASK; + stolen = 0; /* * reuse buf page, if SPLICE_F_MOVE is set @@ -399,6 +405,7 @@ static int pipe_to_file(struct pipe_inode_info *info, struct pipe_buffer *buf, goto find_page; page = buf->page; + stolen = 1; if (add_to_page_cache_lru(page, mapping, index, mapping_gfp_mask(mapping))) goto find_page; @@ -443,10 +450,13 @@ find_page: } ret = mapping->a_ops->prepare_write(file, page, 0, sd->len); - if (ret) + if (ret == AOP_TRUNCATED_PAGE) { + page_cache_release(page); + goto find_page; + } else if (ret) goto out; - if (!buf->stolen) { + if (!stolen) { char *dst = kmap_atomic(page, KM_USER0); memcpy(dst + offset, src + buf->offset, sd->len); @@ -455,16 +465,18 @@ find_page: } ret = mapping->a_ops->commit_write(file, page, 0, sd->len); - if (ret < 0) + if (ret == AOP_TRUNCATED_PAGE) { + page_cache_release(page); + goto find_page; + } else if (ret) goto out; - set_page_dirty(page); - ret = write_one_page(page, 0); + balance_dirty_pages_ratelimited(mapping); out: - if (ret < 0) - unlock_page(page); - if (!buf->stolen) + if (!stolen) { page_cache_release(page); + unlock_page(page); + } buf->ops->unmap(info, buf); return ret; } @@ -576,7 +588,27 @@ static ssize_t move_from_pipe(struct inode *inode, struct file *out, ssize_t generic_file_splice_write(struct inode *inode, struct file *out, size_t len, unsigned int flags) { - return move_from_pipe(inode, out, len, flags, pipe_to_file); + struct address_space *mapping = out->f_mapping; + ssize_t ret = move_from_pipe(inode, out, len, flags, pipe_to_file); + + /* + * if file or inode is SYNC and we actually wrote some data, sync it + */ + if (unlikely((out->f_flags & O_SYNC) || IS_SYNC(mapping->host)) + && ret > 0) { + struct inode *inode = mapping->host; + int err; + + mutex_lock(&inode->i_mutex); + err = generic_osync_inode(mapping->host, mapping, + OSYNC_METADATA|OSYNC_DATA); + mutex_unlock(&inode->i_mutex); + + if (err) + ret = err; + } + + return ret; } ssize_t generic_splice_sendpage(struct inode *inode, struct file *out, |
