This adds a simple iomap-based implementation of the legacy ->bmap
interface. Note that we can't easily add checks for rt or reflink
files, so these will have to remain in the callers. This interface
just needs to die..
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
fs/iomap.c | 34 ++++++++++++++++++++++++++++++++++
include/linux/iomap.h | 3 +++
2 files changed, 37 insertions(+)
diff --git a/fs/iomap.c b/fs/iomap.c
index f928df4ab9a9..fa278ed338ce 100644
--- a/fs/iomap.c
+++ b/fs/iomap.c
@@ -1411,3 +1411,37 @@ int iomap_swapfile_activate(struct swap_info_struct *sis,
}
EXPORT_SYMBOL_GPL(iomap_swapfile_activate);
#endif /* CONFIG_SWAP */
+
+static loff_t
+iomap_bmap_actor(struct inode *inode, loff_t pos, loff_t length,
+ void *data, struct iomap *iomap)
+{
+ sector_t *bno = data, addr;
+
+ if (iomap->type == IOMAP_MAPPED) {
+ addr = (pos - iomap->offset + iomap->addr) >> inode->i_blkbits;
+ if (addr > INT_MAX)
+ WARN(1, "would truncate bmap result\n");
+ else
+ *bno = addr;
+ }
+ return 0;
+}
+
+/* legacy ->bmap interface. 0 is the error return (!) */
+sector_t
+iomap_bmap(struct address_space *mapping, sector_t bno,
+ const struct iomap_ops *ops)
+{
+ struct inode *inode = mapping->host;
+ loff_t pos = bno >> inode->i_blkbits;
+ unsigned blocksize = i_blocksize(inode);
+
+ if (filemap_write_and_wait(mapping))
+ return 0;
+
+ bno = 0;
+ iomap_apply(inode, pos, blocksize, 0, ops, &bno, iomap_bmap_actor);
+ return bno;
+}
+EXPORT_SYMBOL_GPL(iomap_bmap);
diff --git a/include/linux/iomap.h b/include/linux/iomap.h
index 819e0cd2a950..a044a824da85 100644
--- a/include/linux/iomap.h
+++ b/include/linux/iomap.h
@@ -4,6 +4,7 @@
#include <linux/types.h>
+struct address_space;
struct fiemap_extent_info;
struct inode;
struct iov_iter;
@@ -100,6 +101,8 @@ loff_t iomap_seek_hole(struct inode *inode, loff_t offset,
const struct iomap_ops *ops);
loff_t iomap_seek_data(struct inode *inode, loff_t offset,
const struct iomap_ops *ops);
+sector_t iomap_bmap(struct address_space *mapping, sector_t bno,
+ const struct iomap_ops *ops);
/*
* Flags for direct I/O ->end_io:
--
2.17.0
