diff options
| -rw-r--r-- | fs/iomap.c | 84 | ||||
| -rw-r--r-- | include/linux/iomap.h | 3 |
2 files changed, 87 insertions, 0 deletions
diff --git a/fs/iomap.c b/fs/iomap.c index 706270f21b35..ec411a6b9edc 100644 --- a/fs/iomap.c +++ b/fs/iomap.c @@ -252,6 +252,88 @@ iomap_file_buffered_write(struct kiocb *iocb, struct iov_iter *iter, } EXPORT_SYMBOL_GPL(iomap_file_buffered_write); +static struct page * +__iomap_read_page(struct inode *inode, loff_t offset) +{ + struct address_space *mapping = inode->i_mapping; + struct page *page; + + page = read_mapping_page(mapping, offset >> PAGE_SHIFT, NULL); + if (IS_ERR(page)) + return page; + if (!PageUptodate(page)) { + put_page(page); + return ERR_PTR(-EIO); + } + return page; +} + +static loff_t +iomap_dirty_actor(struct inode *inode, loff_t pos, loff_t length, void *data, + struct iomap *iomap) +{ + long status = 0; + ssize_t written = 0; + + do { + struct page *page, *rpage; + unsigned long offset; /* Offset into pagecache page */ + unsigned long bytes; /* Bytes to write to page */ + + offset = (pos & (PAGE_SIZE - 1)); + bytes = min_t(unsigned long, PAGE_SIZE - offset, length); + + rpage = __iomap_read_page(inode, pos); + if (IS_ERR(rpage)) + return PTR_ERR(rpage); + + status = iomap_write_begin(inode, pos, bytes, + AOP_FLAG_NOFS | AOP_FLAG_UNINTERRUPTIBLE, + &page, iomap); + put_page(rpage); + if (unlikely(status)) + return status; + + WARN_ON_ONCE(!PageUptodate(page)); + + status = iomap_write_end(inode, pos, bytes, bytes, page); + if (unlikely(status <= 0)) { + if (WARN_ON_ONCE(status == 0)) + return -EIO; + return status; + } + + cond_resched(); + + pos += status; + written += status; + length -= status; + + balance_dirty_pages_ratelimited(inode->i_mapping); + } while (length); + + return written; +} + +int +iomap_file_dirty(struct inode *inode, loff_t pos, loff_t len, + struct iomap_ops *ops) +{ + loff_t ret; + + while (len) { + ret = iomap_apply(inode, pos, len, IOMAP_WRITE, ops, NULL, + iomap_dirty_actor); + if (ret <= 0) + return ret; + pos += ret; + len -= ret; + } + + return 0; +} +EXPORT_SYMBOL_GPL(iomap_file_dirty); + static int iomap_zero(struct inode *inode, loff_t pos, unsigned offset, unsigned bytes, struct iomap *iomap) { @@ -430,6 +512,8 @@ static int iomap_to_fiemap(struct fiemap_extent_info *fi, if (iomap->flags & IOMAP_F_MERGED) flags |= FIEMAP_EXTENT_MERGED; + if (iomap->flags & IOMAP_F_SHARED) + flags |= FIEMAP_EXTENT_SHARED; return fiemap_fill_next_extent(fi, iomap->offset, iomap->blkno != IOMAP_NULL_BLOCK ? iomap->blkno << 9: 0, diff --git a/include/linux/iomap.h b/include/linux/iomap.h index 3d70ece10313..c74226a738a3 100644 --- a/include/linux/iomap.h +++ b/include/linux/iomap.h @@ -22,6 +22,7 @@ struct vm_fault; * Flags for iomap mappings: */ #define IOMAP_F_MERGED 0x01 /* contains multiple blocks/extents */ +#define IOMAP_F_SHARED 0x02 /* block shared with another file */ /* * Magic value for blkno: @@ -64,6 +65,8 @@ struct iomap_ops { ssize_t iomap_file_buffered_write(struct kiocb *iocb, struct iov_iter *from, struct iomap_ops *ops); +int iomap_file_dirty(struct inode *inode, loff_t pos, loff_t len, + struct iomap_ops *ops); int iomap_zero_range(struct inode *inode, loff_t pos, loff_t len, bool *did_zero, struct iomap_ops *ops); int iomap_truncate_page(struct inode *inode, loff_t pos, bool *did_zero, |