Punch hole on a reflinked file needs dax_iomap_cow_copy() too. Otherwise, data in not aligned area will be not correct. So, add the srcmap to dax_iomap_zero() and replace memset() as dax_iomap_cow_copy().
Signed-off-by: Shiyang Ruan <[email protected]> Reviewed-by: Ritesh Harjani <[email protected]> Reviewed-by: Darrick J. Wong <[email protected]> --- fs/dax.c | 26 ++++++++++++++++---------- fs/iomap/buffered-io.c | 4 ++-- include/linux/dax.h | 3 ++- 3 files changed, 20 insertions(+), 13 deletions(-) diff --git a/fs/dax.c b/fs/dax.c index f4acb79cb811..b294900e574e 100644 --- a/fs/dax.c +++ b/fs/dax.c @@ -1209,7 +1209,8 @@ static vm_fault_t dax_pmd_load_hole(struct xa_state *xas, struct vm_fault *vmf, } #endif /* CONFIG_FS_DAX_PMD */ -s64 dax_iomap_zero(loff_t pos, u64 length, struct iomap *iomap) +s64 dax_iomap_zero(loff_t pos, u64 length, const struct iomap *iomap, + const struct iomap *srcmap) { sector_t sector = iomap_sector(iomap, pos & PAGE_MASK); pgoff_t pgoff; @@ -1231,19 +1232,24 @@ s64 dax_iomap_zero(loff_t pos, u64 length, struct iomap *iomap) if (page_aligned) rc = dax_zero_page_range(iomap->dax_dev, pgoff, 1); - else + else { rc = dax_direct_access(iomap->dax_dev, pgoff, 1, &kaddr, NULL); - if (rc < 0) { - dax_read_unlock(id); - return rc; - } - - if (!page_aligned) { + if (rc < 0) + goto out; memset(kaddr + offset, 0, size); - dax_flush(iomap->dax_dev, kaddr + offset, size); + if (iomap->addr != srcmap->addr) { + rc = dax_iomap_cow_copy(pos, size, PAGE_SIZE, srcmap, + kaddr); + if (rc < 0) + goto out; + dax_flush(iomap->dax_dev, kaddr, PAGE_SIZE); + } else + dax_flush(iomap->dax_dev, kaddr + offset, size); } + +out: dax_read_unlock(id); - return size; + return rc < 0 ? rc : size; } static loff_t dax_iomap_iter(const struct iomap_iter *iomi, diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c index 71b4806266d7..6e8d40877d01 100644 --- a/fs/iomap/buffered-io.c +++ b/fs/iomap/buffered-io.c @@ -889,7 +889,7 @@ static s64 __iomap_zero_iter(struct iomap_iter *iter, loff_t pos, u64 length) static loff_t iomap_zero_iter(struct iomap_iter *iter, bool *did_zero) { - struct iomap *iomap = &iter->iomap; + const struct iomap *iomap = &iter->iomap; const struct iomap *srcmap = iomap_iter_srcmap(iter); loff_t pos = iter->pos; loff_t length = iomap_length(iter); @@ -903,7 +903,7 @@ static loff_t iomap_zero_iter(struct iomap_iter *iter, bool *did_zero) s64 bytes; if (IS_DAX(iter->inode)) - bytes = dax_iomap_zero(pos, length, iomap); + bytes = dax_iomap_zero(pos, length, iomap, srcmap); else bytes = __iomap_zero_iter(iter, pos, length); if (bytes < 0) diff --git a/include/linux/dax.h b/include/linux/dax.h index b52f084aa643..c63559605369 100644 --- a/include/linux/dax.h +++ b/include/linux/dax.h @@ -237,7 +237,8 @@ vm_fault_t dax_finish_sync_fault(struct vm_fault *vmf, int dax_delete_mapping_entry(struct address_space *mapping, pgoff_t index); int dax_invalidate_mapping_entry_sync(struct address_space *mapping, pgoff_t index); -s64 dax_iomap_zero(loff_t pos, u64 length, struct iomap *iomap); +s64 dax_iomap_zero(loff_t pos, u64 length, const struct iomap *iomap, + const struct iomap *srcmap); static inline bool dax_mapping(struct address_space *mapping) { return mapping->host && IS_DAX(mapping->host); -- 2.32.0
