From 6c31f495d19975b7d2e824ee614934d5db113afe Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 19 Sep 2016 11:28:38 +1000 Subject: [PATCH] xfs: use iomap to implement DAX Another users of buffer_heads bytes the dust. Signed-off-by: Christoph Hellwig Reviewed-by: Ross Zwisler Signed-off-by: Dave Chinner --- fs/xfs/xfs_file.c | 61 +++++++++++++--------------------------------- fs/xfs/xfs_iomap.c | 11 ++++++--- 2 files changed, 24 insertions(+), 48 deletions(-) diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c index 62649ccdbb4d..f99d7fac5abf 100644 --- a/fs/xfs/xfs_file.c +++ b/fs/xfs/xfs_file.c @@ -332,10 +332,7 @@ xfs_file_dax_read( struct kiocb *iocb, struct iov_iter *to) { - struct address_space *mapping = iocb->ki_filp->f_mapping; - struct inode *inode = mapping->host; - struct xfs_inode *ip = XFS_I(inode); - struct iov_iter data = *to; + struct xfs_inode *ip = XFS_I(iocb->ki_filp->f_mapping->host); size_t count = iov_iter_count(to); ssize_t ret = 0; @@ -345,11 +342,7 @@ xfs_file_dax_read( return 0; /* skip atime */ xfs_rw_ilock(ip, XFS_IOLOCK_SHARED); - ret = dax_do_io(iocb, inode, &data, xfs_get_blocks_direct, NULL, 0); - if (ret > 0) { - iocb->ki_pos += ret; - iov_iter_advance(to, ret); - } + ret = iomap_dax_rw(iocb, to, &xfs_iomap_ops); xfs_rw_iunlock(ip, XFS_IOLOCK_SHARED); file_accessed(iocb->ki_filp); @@ -711,52 +704,32 @@ xfs_file_dax_write( struct kiocb *iocb, struct iov_iter *from) { - struct address_space *mapping = iocb->ki_filp->f_mapping; - struct inode *inode = mapping->host; + struct inode *inode = iocb->ki_filp->f_mapping->host; struct xfs_inode *ip = XFS_I(inode); - ssize_t ret = 0; int iolock = XFS_IOLOCK_EXCL; - struct iov_iter data; + ssize_t ret, error = 0; + size_t count; + loff_t pos; xfs_rw_ilock(ip, iolock); ret = xfs_file_aio_write_checks(iocb, from, &iolock); if (ret) goto out; - /* - * Yes, even DAX files can have page cache attached to them: A zeroed - * page is inserted into the pagecache when we have to serve a write - * fault on a hole. It should never be dirtied and can simply be - * dropped from the pagecache once we get real data for the page. - * - * XXX: This is racy against mmap, and there's nothing we can do about - * it. dax_do_io() should really do this invalidation internally as - * it will know if we've allocated over a holei for this specific IO and - * if so it needs to update the mapping tree and invalidate existing - * PTEs over the newly allocated range. Remove this invalidation when - * dax_do_io() is fixed up. - */ - if (mapping->nrpages) { - loff_t end = iocb->ki_pos + iov_iter_count(from) - 1; - - ret = invalidate_inode_pages2_range(mapping, - iocb->ki_pos >> PAGE_SHIFT, - end >> PAGE_SHIFT); - WARN_ON_ONCE(ret); - } + pos = iocb->ki_pos; + count = iov_iter_count(from); - trace_xfs_file_dax_write(ip, iov_iter_count(from), iocb->ki_pos); + trace_xfs_file_dax_write(ip, count, pos); - data = *from; - ret = dax_do_io(iocb, inode, &data, xfs_get_blocks_direct, - xfs_end_io_direct_write, 0); - if (ret > 0) { - iocb->ki_pos += ret; - iov_iter_advance(from, ret); + ret = iomap_dax_rw(iocb, from, &xfs_iomap_ops); + if (ret > 0 && iocb->ki_pos > i_size_read(inode)) { + i_size_write(inode, iocb->ki_pos); + error = xfs_setfilesize(ip, pos, ret); } + out: xfs_rw_iunlock(ip, iolock); - return ret; + return error ? error : ret; } STATIC ssize_t @@ -1495,7 +1468,7 @@ xfs_filemap_page_mkwrite( xfs_ilock(XFS_I(inode), XFS_MMAPLOCK_SHARED); if (IS_DAX(inode)) { - ret = dax_mkwrite(vma, vmf, xfs_get_blocks_dax_fault); + ret = iomap_dax_fault(vma, vmf, &xfs_iomap_ops); } else { ret = iomap_page_mkwrite(vma, vmf, &xfs_iomap_ops); ret = block_page_mkwrite_return(ret); @@ -1529,7 +1502,7 @@ xfs_filemap_fault( * changes to xfs_get_blocks_direct() to map unwritten extent * ioend for conversion on read-only mappings. */ - ret = dax_fault(vma, vmf, xfs_get_blocks_dax_fault); + ret = iomap_dax_fault(vma, vmf, &xfs_iomap_ops); } else ret = filemap_fault(vma, vmf); xfs_iunlock(XFS_I(inode), XFS_MMAPLOCK_SHARED); diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c index fe4a26d752d0..c08253e11545 100644 --- a/fs/xfs/xfs_iomap.c +++ b/fs/xfs/xfs_iomap.c @@ -934,11 +934,13 @@ error_on_bmapi_transaction: return error; } -static inline bool imap_needs_alloc(struct xfs_bmbt_irec *imap, int nimaps) +static inline bool imap_needs_alloc(struct inode *inode, + struct xfs_bmbt_irec *imap, int nimaps) { return !nimaps || imap->br_startblock == HOLESTARTBLOCK || - imap->br_startblock == DELAYSTARTBLOCK; + imap->br_startblock == DELAYSTARTBLOCK || + (IS_DAX(inode) && ISUNWRITTEN(imap)); } static int @@ -959,7 +961,8 @@ xfs_file_iomap_begin( if (XFS_FORCED_SHUTDOWN(mp)) return -EIO; - if ((flags & IOMAP_WRITE) && !xfs_get_extsz_hint(ip)) { + if ((flags & IOMAP_WRITE) && + !IS_DAX(inode) && !xfs_get_extsz_hint(ip)) { return xfs_file_iomap_begin_delay(inode, offset, length, flags, iomap); } @@ -979,7 +982,7 @@ xfs_file_iomap_begin( return error; } - if ((flags & IOMAP_WRITE) && imap_needs_alloc(&imap, nimaps)) { + if ((flags & IOMAP_WRITE) && imap_needs_alloc(inode, &imap, nimaps)) { /* * We cap the maximum length we map here to MAX_WRITEBACK_PAGES * pages to keep the chunks of work done where somewhat symmetric -- 2.20.1