Start untangling xfs_file_iomap_begin by splitting out the read-only
case into its own set of iomap_ops with a very simply iomap_begin
helper.
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
fs/xfs/xfs_aops.c | 9 ++++---
fs/xfs/xfs_file.c | 8 +++---
fs/xfs/xfs_iomap.c | 61 ++++++++++++++++++++++++++++++++++------------
fs/xfs/xfs_iomap.h | 1 +
fs/xfs/xfs_iops.c | 2 +-
5 files changed, 58 insertions(+), 23 deletions(-)
diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c
index 807af5c3c347..f708a2831d2f 100644
--- a/fs/xfs/xfs_aops.c
+++ b/fs/xfs/xfs_aops.c
@@ -635,7 +635,7 @@ xfs_vm_bmap(
*/
if (xfs_is_cow_inode(ip) || XFS_IS_REALTIME_INODE(ip))
return 0;
- return iomap_bmap(mapping, block, &xfs_iomap_ops);
+ return iomap_bmap(mapping, block, &xfs_read_iomap_ops);
}
STATIC int
@@ -643,7 +643,7 @@ xfs_vm_readpage(
struct file *unused,
struct page *page)
{
- return iomap_readpage(page, &xfs_iomap_ops);
+ return iomap_readpage(page, &xfs_read_iomap_ops);
}
STATIC int
@@ -653,7 +653,7 @@ xfs_vm_readpages(
struct list_head *pages,
unsigned nr_pages)
{
- return iomap_readpages(mapping, pages, nr_pages, &xfs_iomap_ops);
+ return iomap_readpages(mapping, pages, nr_pages, &xfs_read_iomap_ops);
}
static int
@@ -663,7 +663,8 @@ xfs_iomap_swapfile_activate(
sector_t *span)
{
sis->bdev = xfs_find_bdev_for_inode(file_inode(swap_file));
- return iomap_swapfile_activate(sis, swap_file, span, &xfs_iomap_ops);
+ return iomap_swapfile_activate(sis, swap_file, span,
+ &xfs_read_iomap_ops);
}
const struct address_space_operations xfs_address_space_operations = {
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index 1ffb179f35d2..f9814306ed8e 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -188,7 +188,7 @@ xfs_file_dio_aio_read(
file_accessed(iocb->ki_filp);
xfs_ilock(ip, XFS_IOLOCK_SHARED);
- ret = iomap_dio_rw(iocb, to, &xfs_iomap_ops, NULL);
+ ret = iomap_dio_rw(iocb, to, &xfs_read_iomap_ops, NULL);
xfs_iunlock(ip, XFS_IOLOCK_SHARED);
return ret;
@@ -215,7 +215,7 @@ xfs_file_dax_read(
xfs_ilock(ip, XFS_IOLOCK_SHARED);
}
- ret = dax_iomap_rw(iocb, to, &xfs_iomap_ops);
+ ret = dax_iomap_rw(iocb, to, &xfs_read_iomap_ops);
xfs_iunlock(ip, XFS_IOLOCK_SHARED);
file_accessed(iocb->ki_filp);
@@ -1156,7 +1156,9 @@ __xfs_filemap_fault(
if (IS_DAX(inode)) {
pfn_t pfn;
- ret = dax_iomap_fault(vmf, pe_size, &pfn, NULL, &xfs_iomap_ops);
+ ret = dax_iomap_fault(vmf, pe_size, &pfn, NULL,
+ (write_fault && !vmf->cow_page) ?
+ &xfs_iomap_ops : &xfs_read_iomap_ops);
if (ret & VM_FAULT_NEEDDSYNC)
ret = dax_finish_sync_fault(vmf, pe_size, pfn);
} else {
diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c
index a9f9e8c9034a..0cfd973fd192 100644
--- a/fs/xfs/xfs_iomap.c
+++ b/fs/xfs/xfs_iomap.c
@@ -950,11 +950,13 @@ xfs_file_iomap_begin(
u16 iomap_flags = 0;
unsigned lockmode;
+ ASSERT(flags & (IOMAP_WRITE | IOMAP_ZERO));
+
if (XFS_FORCED_SHUTDOWN(mp))
return -EIO;
- if ((flags & (IOMAP_WRITE | IOMAP_ZERO)) && !(flags & IOMAP_DIRECT) &&
- !IS_DAX(inode) && !xfs_get_extsz_hint(ip)) {
+ if (!(flags & IOMAP_DIRECT) && !IS_DAX(inode) &&
+ !xfs_get_extsz_hint(ip)) {
/* Reserve delalloc blocks for regular writeback. */
return xfs_file_iomap_begin_delay(inode, offset, length, flags,
iomap, srcmap);
@@ -975,17 +977,6 @@ xfs_file_iomap_begin(
if (error)
goto out_unlock;
- if (flags & IOMAP_REPORT) {
- /* Trim the mapping to the nearest shared extent boundary. */
- error = xfs_reflink_trim_around_shared(ip, &imap, &shared);
- if (error)
- goto out_unlock;
- }
-
- /* Non-modifying mapping requested, so we are done */
- if (!(flags & (IOMAP_WRITE | IOMAP_ZERO)))
- goto out_found;
-
/*
* Break shared extents if necessary. Checks for non-blocking IO have
* been done up front, so we don't need to do them here.
@@ -1046,8 +1037,6 @@ xfs_file_iomap_begin(
trace_xfs_iomap_alloc(ip, offset, length, XFS_DATA_FORK, &imap);
out_finish:
- if (shared)
- iomap_flags |= IOMAP_F_SHARED;
return xfs_bmbt_to_iomap(ip, iomap, &imap, iomap_flags);
out_found:
@@ -1150,6 +1139,48 @@ const struct iomap_ops xfs_iomap_ops = {
.iomap_end = xfs_file_iomap_end,
};
+static int
+xfs_read_iomap_begin(
+ struct inode *inode,
+ loff_t offset,
+ loff_t length,
+ unsigned flags,
+ struct iomap *iomap,
+ struct iomap *srcmap)
+{
+ struct xfs_inode *ip = XFS_I(inode);
+ struct xfs_mount *mp = ip->i_mount;
+ struct xfs_bmbt_irec imap;
+ xfs_fileoff_t offset_fsb = XFS_B_TO_FSBT(mp, offset);
+ xfs_fileoff_t end_fsb = xfs_iomap_end_fsb(mp, offset, length);
+ int nimaps = 1, error = 0;
+ bool shared = false;
+ unsigned lockmode;
+
+ ASSERT(!(flags & (IOMAP_WRITE | IOMAP_ZERO)));
+
+ if (XFS_FORCED_SHUTDOWN(mp))
+ return -EIO;
+
+ error = xfs_ilock_for_iomap(ip, flags, &lockmode);
+ if (error)
+ return error;
+ error = xfs_bmapi_read(ip, offset_fsb, end_fsb - offset_fsb, &imap,
+ &nimaps, 0);
+ if (!error && (flags & IOMAP_REPORT))
+ error = xfs_reflink_trim_around_shared(ip, &imap, &shared);
+ xfs_iunlock(ip, lockmode);
+
+ if (error)
+ return error;
+ trace_xfs_iomap_found(ip, offset, length, XFS_DATA_FORK, &imap);
+ return xfs_bmbt_to_iomap(ip, iomap, &imap, shared ? IOMAP_F_SHARED : 0);
+}
+
+const struct iomap_ops xfs_read_iomap_ops = {
+ .iomap_begin = xfs_read_iomap_begin,
+};
+
static int
xfs_seek_iomap_begin(
struct inode *inode,
diff --git a/fs/xfs/xfs_iomap.h b/fs/xfs/xfs_iomap.h
index 71d0ae460c44..61b1fc3e5143 100644
--- a/fs/xfs/xfs_iomap.h
+++ b/fs/xfs/xfs_iomap.h
@@ -40,6 +40,7 @@ xfs_aligned_fsb_count(
}
extern const struct iomap_ops xfs_iomap_ops;
+extern const struct iomap_ops xfs_read_iomap_ops;
extern const struct iomap_ops xfs_seek_iomap_ops;
extern const struct iomap_ops xfs_xattr_iomap_ops;
diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
index fe285d123d69..9c448a54a951 100644
--- a/fs/xfs/xfs_iops.c
+++ b/fs/xfs/xfs_iops.c
@@ -1114,7 +1114,7 @@ xfs_vn_fiemap(
&xfs_xattr_iomap_ops);
} else {
error = iomap_fiemap(inode, fieinfo, start, length,
- &xfs_iomap_ops);
+ &xfs_read_iomap_ops);
}
xfs_iunlock(XFS_I(inode), XFS_IOLOCK_SHARED);
--
2.20.1
