| Message ID | 20210816060359.1442450-5-ruansy.fnst@fujitsu.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | fsdax,xfs: Add reflink&dedupe support for fsdax | expand |
On Sun, Aug 15, 2021 at 11:04 PM Shiyang Ruan <ruansy.fnst@fujitsu.com> wrote: > > 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 <ruansy.fnst@fujitsu.com> > Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com> > Reviewed-by: Darrick J. Wong <djwong@kernel.org> > --- > fs/dax.c | 25 +++++++++++++++---------- > fs/iomap/buffered-io.c | 4 ++-- > include/linux/dax.h | 3 ++- > 3 files changed, 19 insertions(+), 13 deletions(-) > > diff --git a/fs/dax.c b/fs/dax.c > index e49ba68cc7e4..91ceb518f66a 100644 > --- a/fs/dax.c > +++ b/fs/dax.c > @@ -1198,7 +1198,8 @@ 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; > @@ -1220,19 +1221,23 @@ 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) { > - memset(kaddr + offset, 0, size); > + if (rc < 0) > + goto out; > + if (iomap->addr != srcmap->addr) { > + rc = dax_iomap_cow_copy(pos, size, PAGE_SIZE, srcmap, > + kaddr); Apologies, I'm confused, why is it ok to skip zeroing here?
On 2021/8/20 10:39, Dan Williams wrote: > On Sun, Aug 15, 2021 at 11:04 PM Shiyang Ruan <ruansy.fnst@fujitsu.com> wrote: >> >> 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 <ruansy.fnst@fujitsu.com> >> Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com> >> Reviewed-by: Darrick J. Wong <djwong@kernel.org> >> --- >> fs/dax.c | 25 +++++++++++++++---------- >> fs/iomap/buffered-io.c | 4 ++-- >> include/linux/dax.h | 3 ++- >> 3 files changed, 19 insertions(+), 13 deletions(-) >> >> diff --git a/fs/dax.c b/fs/dax.c >> index e49ba68cc7e4..91ceb518f66a 100644 >> --- a/fs/dax.c >> +++ b/fs/dax.c >> @@ -1198,7 +1198,8 @@ 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; >> @@ -1220,19 +1221,23 @@ 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) { >> - memset(kaddr + offset, 0, size); >> + if (rc < 0) >> + goto out; >> + if (iomap->addr != srcmap->addr) { >> + rc = dax_iomap_cow_copy(pos, size, PAGE_SIZE, srcmap, >> + kaddr); > > Apologies, I'm confused, why is it ok to skip zeroing here? > That was a mistake. Will be fixed in next version. -- Thanks, Ruan.
diff --git a/fs/dax.c b/fs/dax.c index e49ba68cc7e4..91ceb518f66a 100644 --- a/fs/dax.c +++ b/fs/dax.c @@ -1198,7 +1198,8 @@ 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; @@ -1220,19 +1221,23 @@ 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) { - memset(kaddr + offset, 0, size); + if (rc < 0) + goto out; + if (iomap->addr != srcmap->addr) { + rc = dax_iomap_cow_copy(pos, size, PAGE_SIZE, srcmap, + kaddr); + if (rc < 0) + goto out; + } else + memset(kaddr + offset, 0, size); 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);