From: Goldwyn Rodrigues <rgoldwyn@xxxxxxxx> A preparation patch for copy-on-write (CoW). The srcmap is used to identify where the read is to be performed from. This is passed to iomap->begin() of the respective filesystem, which is supposed to put in the details for reading before performing the copy for CoW. Signed-off-by: Goldwyn Rodrigues <rgoldwyn@xxxxxxxx> --- fs/dax.c | 8 +++++--- fs/ext2/inode.c | 2 +- fs/ext4/inode.c | 2 +- fs/gfs2/bmap.c | 3 ++- fs/iomap/apply.c | 5 +++-- fs/iomap/buffered-io.c | 14 +++++++------- fs/iomap/direct-io.c | 2 +- fs/iomap/fiemap.c | 4 ++-- fs/iomap/seek.c | 4 ++-- fs/iomap/swapfile.c | 3 ++- fs/xfs/xfs_iomap.c | 9 ++++++--- include/linux/iomap.h | 5 +++-- 12 files changed, 35 insertions(+), 26 deletions(-) diff --git a/fs/dax.c b/fs/dax.c index 6bf81f931de3..e961d8dc23ef 100644 --- a/fs/dax.c +++ b/fs/dax.c @@ -1090,7 +1090,7 @@ EXPORT_SYMBOL_GPL(__dax_zero_page_range); static loff_t dax_iomap_actor(struct inode *inode, loff_t pos, loff_t length, void *data, - struct iomap *iomap) + struct iomap *iomap, struct iomap *srcmap) { struct block_device *bdev = iomap->bdev; struct dax_device *dax_dev = iomap->dax_dev; @@ -1248,6 +1248,7 @@ static vm_fault_t dax_iomap_pte_fault(struct vm_fault *vmf, pfn_t *pfnp, unsigned long vaddr = vmf->address; loff_t pos = (loff_t)vmf->pgoff << PAGE_SHIFT; struct iomap iomap = { 0 }; + struct iomap srcmap = { 0 }; unsigned flags = IOMAP_FAULT; int error, major = 0; bool write = vmf->flags & FAULT_FLAG_WRITE; @@ -1292,7 +1293,7 @@ static vm_fault_t dax_iomap_pte_fault(struct vm_fault *vmf, pfn_t *pfnp, * the file system block size to be equal the page size, which means * that we never have to deal with more than a single extent here. */ - error = ops->iomap_begin(inode, pos, PAGE_SIZE, flags, &iomap); + error = ops->iomap_begin(inode, pos, PAGE_SIZE, flags, &iomap, &srcmap); if (iomap_errp) *iomap_errp = error; if (error) { @@ -1472,6 +1473,7 @@ static vm_fault_t dax_iomap_pmd_fault(struct vm_fault *vmf, pfn_t *pfnp, struct inode *inode = mapping->host; vm_fault_t result = VM_FAULT_FALLBACK; struct iomap iomap = { 0 }; + struct iomap srcmap = { 0 }; pgoff_t max_pgoff; void *entry; loff_t pos; @@ -1546,7 +1548,7 @@ static vm_fault_t dax_iomap_pmd_fault(struct vm_fault *vmf, pfn_t *pfnp, * to look up our filesystem block. */ pos = (loff_t)xas.xa_index << PAGE_SHIFT; - error = ops->iomap_begin(inode, pos, PMD_SIZE, iomap_flags, &iomap); + error = ops->iomap_begin(inode, pos, PMD_SIZE, iomap_flags, &iomap, &srcmap); if (error) goto unlock_entry; diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c index 7004ce581a32..467c13ff6b40 100644 --- a/fs/ext2/inode.c +++ b/fs/ext2/inode.c @@ -801,7 +801,7 @@ int ext2_get_block(struct inode *inode, sector_t iblock, #ifdef CONFIG_FS_DAX static int ext2_iomap_begin(struct inode *inode, loff_t offset, loff_t length, - unsigned flags, struct iomap *iomap) + unsigned flags, struct iomap *iomap, struct iomap *srcmap) { unsigned int blkbits = inode->i_blkbits; unsigned long first_block = offset >> blkbits; diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 420fe3deed39..918f94eff799 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -3453,7 +3453,7 @@ static bool ext4_inode_datasync_dirty(struct inode *inode) } static int ext4_iomap_begin(struct inode *inode, loff_t offset, loff_t length, - unsigned flags, struct iomap *iomap) + unsigned flags, struct iomap *iomap, struct iomap *srcmap) { struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); unsigned int blkbits = inode->i_blkbits; diff --git a/fs/gfs2/bmap.c b/fs/gfs2/bmap.c index 4f8b5fd6c81f..0189262989f2 100644 --- a/fs/gfs2/bmap.c +++ b/fs/gfs2/bmap.c @@ -1164,7 +1164,8 @@ static int gfs2_iomap_begin_write(struct inode *inode, loff_t pos, } static int gfs2_iomap_begin(struct inode *inode, loff_t pos, loff_t length, - unsigned flags, struct iomap *iomap) + unsigned flags, struct iomap *iomap, + struct iomap *srcmap) { struct gfs2_inode *ip = GFS2_I(inode); struct metapath mp = { .mp_aheight = 1, }; diff --git a/fs/iomap/apply.c b/fs/iomap/apply.c index 54c02aecf3cd..6cdb362fff36 100644 --- a/fs/iomap/apply.c +++ b/fs/iomap/apply.c @@ -24,6 +24,7 @@ iomap_apply(struct inode *inode, loff_t pos, loff_t length, unsigned flags, const struct iomap_ops *ops, void *data, iomap_actor_t actor) { struct iomap iomap = { 0 }; + struct iomap srcmap = { 0 }; loff_t written = 0, ret; /* @@ -38,7 +39,7 @@ iomap_apply(struct inode *inode, loff_t pos, loff_t length, unsigned flags, * expose transient stale data. If the reserve fails, we can safely * back out at this point as there is nothing to undo. */ - ret = ops->iomap_begin(inode, pos, length, flags, &iomap); + ret = ops->iomap_begin(inode, pos, length, flags, &iomap, &srcmap); if (ret) return ret; if (WARN_ON(iomap.offset > pos)) @@ -58,7 +59,7 @@ iomap_apply(struct inode *inode, loff_t pos, loff_t length, unsigned flags, * we can do the copy-in page by page without having to worry about * failures exposing transient data. */ - written = actor(inode, pos, length, data, &iomap); + written = actor(inode, pos, length, data, &iomap, &srcmap); /* * Now the data has been copied, commit the range we've copied. This diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c index e25901ae3ff4..f27756c0b31c 100644 --- a/fs/iomap/buffered-io.c +++ b/fs/iomap/buffered-io.c @@ -205,7 +205,7 @@ iomap_read_inline_data(struct inode *inode, struct page *page, static loff_t iomap_readpage_actor(struct inode *inode, loff_t pos, loff_t length, void *data, - struct iomap *iomap) + struct iomap *iomap, struct iomap *srcmap) { struct iomap_readpage_ctx *ctx = data; struct page *page = ctx->cur_page; @@ -351,7 +351,7 @@ iomap_next_page(struct inode *inode, struct list_head *pages, loff_t pos, static loff_t iomap_readpages_actor(struct inode *inode, loff_t pos, loff_t length, - void *data, struct iomap *iomap) + void *data, struct iomap *iomap, struct iomap *srcmap) { struct iomap_readpage_ctx *ctx = data; loff_t done, ret; @@ -371,7 +371,7 @@ iomap_readpages_actor(struct inode *inode, loff_t pos, loff_t length, ctx->cur_page_in_bio = false; } ret = iomap_readpage_actor(inode, pos + done, length - done, - ctx, iomap); + ctx, iomap, srcmap); } return done; @@ -736,7 +736,7 @@ iomap_write_end(struct inode *inode, loff_t pos, unsigned len, static loff_t iomap_write_actor(struct inode *inode, loff_t pos, loff_t length, void *data, - struct iomap *iomap) + struct iomap *iomap, struct iomap *srcmap) { struct iov_iter *i = data; long status = 0; @@ -853,7 +853,7 @@ __iomap_read_page(struct inode *inode, loff_t offset) static loff_t iomap_dirty_actor(struct inode *inode, loff_t pos, loff_t length, void *data, - struct iomap *iomap) + struct iomap *iomap, struct iomap *srcmap) { long status = 0; ssize_t written = 0; @@ -942,7 +942,7 @@ static int iomap_dax_zero(loff_t pos, unsigned offset, unsigned bytes, static loff_t iomap_zero_range_actor(struct inode *inode, loff_t pos, loff_t count, - void *data, struct iomap *iomap) + void *data, struct iomap *iomap, struct iomap *srcmap) { bool *did_zero = data; loff_t written = 0; @@ -1011,7 +1011,7 @@ EXPORT_SYMBOL_GPL(iomap_truncate_page); static loff_t iomap_page_mkwrite_actor(struct inode *inode, loff_t pos, loff_t length, - void *data, struct iomap *iomap) + void *data, struct iomap *iomap, struct iomap *srcmap) { struct page *page = data; int ret; diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c index 1fc28c2da279..e3ccbf7daaae 100644 --- a/fs/iomap/direct-io.c +++ b/fs/iomap/direct-io.c @@ -358,7 +358,7 @@ iomap_dio_inline_actor(struct inode *inode, loff_t pos, loff_t length, static loff_t iomap_dio_actor(struct inode *inode, loff_t pos, loff_t length, - void *data, struct iomap *iomap) + void *data, struct iomap *iomap, struct iomap *srcmap) { struct iomap_dio *dio = data; diff --git a/fs/iomap/fiemap.c b/fs/iomap/fiemap.c index f26fdd36e383..690ef2d7c6c8 100644 --- a/fs/iomap/fiemap.c +++ b/fs/iomap/fiemap.c @@ -44,7 +44,7 @@ static int iomap_to_fiemap(struct fiemap_extent_info *fi, static loff_t iomap_fiemap_actor(struct inode *inode, loff_t pos, loff_t length, void *data, - struct iomap *iomap) + struct iomap *iomap, struct iomap *srcmap) { struct fiemap_ctx *ctx = data; loff_t ret = length; @@ -111,7 +111,7 @@ EXPORT_SYMBOL_GPL(iomap_fiemap); static loff_t iomap_bmap_actor(struct inode *inode, loff_t pos, loff_t length, - void *data, struct iomap *iomap) + void *data, struct iomap *iomap, struct iomap *srcmap) { sector_t *bno = data, addr; diff --git a/fs/iomap/seek.c b/fs/iomap/seek.c index c04bad4b2b43..89f61d93c0bc 100644 --- a/fs/iomap/seek.c +++ b/fs/iomap/seek.c @@ -119,7 +119,7 @@ page_cache_seek_hole_data(struct inode *inode, loff_t offset, loff_t length, static loff_t iomap_seek_hole_actor(struct inode *inode, loff_t offset, loff_t length, - void *data, struct iomap *iomap) + void *data, struct iomap *iomap, struct iomap *srcmap) { switch (iomap->type) { case IOMAP_UNWRITTEN: @@ -165,7 +165,7 @@ EXPORT_SYMBOL_GPL(iomap_seek_hole); static loff_t iomap_seek_data_actor(struct inode *inode, loff_t offset, loff_t length, - void *data, struct iomap *iomap) + void *data, struct iomap *iomap, struct iomap *srcmap) { switch (iomap->type) { case IOMAP_HOLE: diff --git a/fs/iomap/swapfile.c b/fs/iomap/swapfile.c index 152a230f668d..a648dbf6991e 100644 --- a/fs/iomap/swapfile.c +++ b/fs/iomap/swapfile.c @@ -76,7 +76,8 @@ static int iomap_swapfile_add_extent(struct iomap_swapfile_info *isi) * distinction between written and unwritten extents. */ static loff_t iomap_swapfile_activate_actor(struct inode *inode, loff_t pos, - loff_t count, void *data, struct iomap *iomap) + loff_t count, void *data, struct iomap *iomap, + struct iomap *srcmap) { struct iomap_swapfile_info *isi = data; int error; diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c index 3a4310d7cb59..8321733c16c3 100644 --- a/fs/xfs/xfs_iomap.c +++ b/fs/xfs/xfs_iomap.c @@ -922,7 +922,8 @@ xfs_file_iomap_begin( loff_t offset, loff_t length, unsigned flags, - struct iomap *iomap) + struct iomap *iomap, + struct iomap *srcmap) { struct xfs_inode *ip = XFS_I(inode); struct xfs_mount *mp = ip->i_mount; @@ -1145,7 +1146,8 @@ xfs_seek_iomap_begin( loff_t offset, loff_t length, unsigned flags, - struct iomap *iomap) + struct iomap *iomap, + struct iomap *srcmap) { struct xfs_inode *ip = XFS_I(inode); struct xfs_mount *mp = ip->i_mount; @@ -1231,7 +1233,8 @@ xfs_xattr_iomap_begin( loff_t offset, loff_t length, unsigned flags, - struct iomap *iomap) + struct iomap *iomap, + struct iomap *srcmap) { struct xfs_inode *ip = XFS_I(inode); struct xfs_mount *mp = ip->i_mount; diff --git a/include/linux/iomap.h b/include/linux/iomap.h index 7aa5d6117936..9782a79dde59 100644 --- a/include/linux/iomap.h +++ b/include/linux/iomap.h @@ -110,7 +110,8 @@ struct iomap_ops { * The actual length is returned in iomap->length. */ int (*iomap_begin)(struct inode *inode, loff_t pos, loff_t length, - unsigned flags, struct iomap *iomap); + unsigned flags, struct iomap *iomap, + struct iomap *srcmap); /* * Commit and/or unreserve space previous allocated using iomap_begin. @@ -126,7 +127,7 @@ struct iomap_ops { * Main iomap iterator function. */ typedef loff_t (*iomap_actor_t)(struct inode *inode, loff_t pos, loff_t len, - void *data, struct iomap *iomap); + void *data, struct iomap *iomap, struct iomap *srcmap); loff_t iomap_apply(struct inode *inode, loff_t pos, loff_t length, unsigned flags, const struct iomap_ops *ops, void *data, -- 2.16.4