diff options
author | Dave Chinner <david@fromorbit.com> | 2015-11-03 02:28:41 (GMT) |
---|---|---|
committer | Dave Chinner <david@fromorbit.com> | 2015-11-03 02:28:41 (GMT) |
commit | 264e89ad3412ce1e2977e5e807bcf7d20d3b0a59 (patch) | |
tree | 53841fc9aed8f419765e41af5879e18d51982ca0 /fs/xfs/xfs_aops.c | |
parent | 2da5c4b05ab55225f5d1fcc8c1c37d1918232bf4 (diff) | |
parent | 13ad4fe3e087ab66a140f1e00d98f28aa4e3bb28 (diff) | |
download | linux-264e89ad3412ce1e2977e5e807bcf7d20d3b0a59.tar.xz |
Merge branch 'xfs-dax-updates' into for-next
Diffstat (limited to 'fs/xfs/xfs_aops.c')
-rw-r--r-- | fs/xfs/xfs_aops.c | 96 |
1 files changed, 50 insertions, 46 deletions
diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c index e4fff58..29e7e5d 100644 --- a/fs/xfs/xfs_aops.c +++ b/fs/xfs/xfs_aops.c @@ -1259,13 +1259,28 @@ xfs_vm_releasepage( * the DIO. There is only going to be one reference to the ioend and its life * cycle is constrained by the DIO completion code. hence we don't need * reference counting here. + * + * Note that for DIO, an IO to the highest supported file block offset (i.e. + * 2^63 - 1FSB bytes) will result in the offset + count overflowing a signed 64 + * bit variable. Hence if we see this overflow, we have to assume that the IO is + * extending the file size. We won't know for sure until IO completion is run + * and the actual max write offset is communicated to the IO completion + * routine. + * + * For DAX page faults, we are preparing to never see unwritten extents here, + * nor should we ever extend the inode size. Hence we will soon have nothing to + * do here for this case, ensuring we don't have to provide an IO completion + * callback to free an ioend that we don't actually need for a fault into the + * page at offset (2^63 - 1FSB) bytes. */ + static void xfs_map_direct( struct inode *inode, struct buffer_head *bh_result, struct xfs_bmbt_irec *imap, - xfs_off_t offset) + xfs_off_t offset, + bool dax_fault) { struct xfs_ioend *ioend; xfs_off_t size = bh_result->b_size; @@ -1278,6 +1293,13 @@ xfs_map_direct( trace_xfs_gbmap_direct(XFS_I(inode), offset, size, type, imap); + if (dax_fault) { + ASSERT(type == XFS_IO_OVERWRITE); + trace_xfs_gbmap_direct_none(XFS_I(inode), offset, size, type, + imap); + return; + } + if (bh_result->b_private) { ioend = bh_result->b_private; ASSERT(ioend->io_size > 0); @@ -1292,7 +1314,8 @@ xfs_map_direct( ioend->io_size, ioend->io_type, imap); } else if (type == XFS_IO_UNWRITTEN || - offset + size > i_size_read(inode)) { + offset + size > i_size_read(inode) || + offset + size < 0) { ioend = xfs_alloc_ioend(inode, type); ioend->io_offset = offset; ioend->io_size = size; @@ -1354,7 +1377,8 @@ __xfs_get_blocks( sector_t iblock, struct buffer_head *bh_result, int create, - bool direct) + bool direct, + bool dax_fault) { struct xfs_inode *ip = XFS_I(inode); struct xfs_mount *mp = ip->i_mount; @@ -1402,10 +1426,12 @@ __xfs_get_blocks( if (error) goto out_unlock; + /* for DAX, we convert unwritten extents directly */ if (create && (!nimaps || (imap.br_startblock == HOLESTARTBLOCK || - imap.br_startblock == DELAYSTARTBLOCK))) { + imap.br_startblock == DELAYSTARTBLOCK) || + (IS_DAX(inode) && ISUNWRITTEN(&imap)))) { if (direct || xfs_get_extsz_hint(ip)) { /* * xfs_iomap_write_direct() expects the shared lock. It @@ -1450,6 +1476,12 @@ __xfs_get_blocks( goto out_unlock; } + if (IS_DAX(inode) && create) { + ASSERT(!ISUNWRITTEN(&imap)); + /* zeroing is not needed at a higher layer */ + new = 0; + } + /* trim mapping down to size requested */ if (direct || size > (1 << inode->i_blkbits)) xfs_map_trim_size(inode, iblock, bh_result, @@ -1467,7 +1499,8 @@ __xfs_get_blocks( set_buffer_unwritten(bh_result); /* direct IO needs special help */ if (create && direct) - xfs_map_direct(inode, bh_result, &imap, offset); + xfs_map_direct(inode, bh_result, &imap, offset, + dax_fault); } /* @@ -1514,7 +1547,7 @@ xfs_get_blocks( struct buffer_head *bh_result, int create) { - return __xfs_get_blocks(inode, iblock, bh_result, create, false); + return __xfs_get_blocks(inode, iblock, bh_result, create, false, false); } int @@ -1524,7 +1557,17 @@ xfs_get_blocks_direct( struct buffer_head *bh_result, int create) { - return __xfs_get_blocks(inode, iblock, bh_result, create, true); + return __xfs_get_blocks(inode, iblock, bh_result, create, true, false); +} + +int +xfs_get_blocks_dax_fault( + struct inode *inode, + sector_t iblock, + struct buffer_head *bh_result, + int create) +{ + return __xfs_get_blocks(inode, iblock, bh_result, create, true, true); } static void @@ -1623,45 +1666,6 @@ xfs_end_io_direct_write( __xfs_end_io_direct_write(inode, ioend, offset, size); } -/* - * For DAX we need a mapping buffer callback for unwritten extent conversion - * when page faults allocate blocks and then zero them. Note that in this - * case the mapping indicated by the ioend may extend beyond EOF. We most - * definitely do not want to extend EOF here, so we trim back the ioend size to - * EOF. - */ -#ifdef CONFIG_FS_DAX -void -xfs_end_io_dax_write( - struct buffer_head *bh, - int uptodate) -{ - struct xfs_ioend *ioend = bh->b_private; - struct inode *inode = ioend->io_inode; - ssize_t size = ioend->io_size; - - ASSERT(IS_DAX(ioend->io_inode)); - - /* if there was an error zeroing, then don't convert it */ - if (!uptodate) - ioend->io_error = -EIO; - - /* - * Trim update to EOF, so we don't extend EOF during unwritten extent - * conversion of partial EOF blocks. - */ - spin_lock(&XFS_I(inode)->i_flags_lock); - if (ioend->io_offset + size > i_size_read(inode)) - size = i_size_read(inode) - ioend->io_offset; - spin_unlock(&XFS_I(inode)->i_flags_lock); - - __xfs_end_io_direct_write(inode, ioend, ioend->io_offset, size); - -} -#else -void xfs_end_io_dax_write(struct buffer_head *bh, int uptodate) { } -#endif - static inline ssize_t xfs_vm_do_dio( struct inode *inode, |