fsdax,xfs: port unshare to fsdax

Implement unshare in fsdax mode: copy data from srcmap to iomap.

Link: https://lkml.kernel.org/r/1669908753-169-1-git-send-email-ruansy.fnst@fujitsu.com
Signed-off-by: Shiyang Ruan <ruansy.fnst@fujitsu.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Shiyang Ruan 2022-12-01 15:32:33 +00:00 committed by Andrew Morton
parent 64e6edc185
commit d984648e42
3 changed files with 60 additions and 2 deletions

View File

@ -1245,6 +1245,58 @@ static vm_fault_t dax_pmd_load_hole(struct xa_state *xas, struct vm_fault *vmf,
}
#endif /* CONFIG_FS_DAX_PMD */
static s64 dax_unshare_iter(struct iomap_iter *iter)
{
struct iomap *iomap = &iter->iomap;
const struct iomap *srcmap = iomap_iter_srcmap(iter);
loff_t pos = iter->pos;
loff_t length = iomap_length(iter);
int id = 0;
s64 ret = 0;
void *daddr = NULL, *saddr = NULL;
/* don't bother with blocks that are not shared to start with */
if (!(iomap->flags & IOMAP_F_SHARED))
return length;
/* don't bother with holes or unwritten extents */
if (srcmap->type == IOMAP_HOLE || srcmap->type == IOMAP_UNWRITTEN)
return length;
id = dax_read_lock();
ret = dax_iomap_direct_access(iomap, pos, length, &daddr, NULL);
if (ret < 0)
goto out_unlock;
ret = dax_iomap_direct_access(srcmap, pos, length, &saddr, NULL);
if (ret < 0)
goto out_unlock;
ret = copy_mc_to_kernel(daddr, saddr, length);
if (ret)
ret = -EIO;
out_unlock:
dax_read_unlock(id);
return ret;
}
int dax_file_unshare(struct inode *inode, loff_t pos, loff_t len,
const struct iomap_ops *ops)
{
struct iomap_iter iter = {
.inode = inode,
.pos = pos,
.len = len,
.flags = IOMAP_WRITE | IOMAP_UNSHARE | IOMAP_DAX,
};
int ret;
while ((ret = iomap_iter(&iter, ops)) > 0)
iter.processed = dax_unshare_iter(&iter);
return ret;
}
EXPORT_SYMBOL_GPL(dax_file_unshare);
static int dax_memzero(struct iomap_iter *iter, loff_t pos, size_t size)
{
const struct iomap *iomap = &iter->iomap;

View File

@ -1693,8 +1693,12 @@ xfs_reflink_unshare(
inode_dio_wait(inode);
error = iomap_file_unshare(inode, offset, len,
&xfs_buffered_write_iomap_ops);
if (IS_DAX(inode))
error = dax_file_unshare(inode, offset, len,
&xfs_dax_write_iomap_ops);
else
error = iomap_file_unshare(inode, offset, len,
&xfs_buffered_write_iomap_ops);
if (error)
goto out;

View File

@ -205,6 +205,8 @@ static inline void dax_unlock_mapping_entry(struct address_space *mapping,
}
#endif
int dax_file_unshare(struct inode *inode, loff_t pos, loff_t len,
const struct iomap_ops *ops);
int dax_zero_range(struct inode *inode, loff_t pos, loff_t len, bool *did_zero,
const struct iomap_ops *ops);
int dax_truncate_page(struct inode *inode, loff_t pos, bool *did_zero,