Add buffered write support for IOMAP_IN_MEM iomaps. This lets
IOMAP_IN_MEM iomaps use some of the internal features in iomaps
such as granular dirty tracking for large folios.
Signed-off-by: Joanne Koong <joannelkoong@xxxxxxxxx>
---
fs/iomap/buffered-io.c | 24 +++++++++++++++++-------
include/linux/iomap.h | 10 ++++++++++
2 files changed, 27 insertions(+), 7 deletions(-)
diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
index 1caeb4921035..fd2ea1306d88 100644
--- a/fs/iomap/buffered-io.c
+++ b/fs/iomap/buffered-io.c
@@ -300,7 +300,7 @@ static inline bool iomap_block_needs_zeroing(const struct iomap_iter *iter,
{
const struct iomap *srcmap = iomap_iter_srcmap(iter);
- return srcmap->type != IOMAP_MAPPED ||
+ return (srcmap->type != IOMAP_MAPPED && srcmap->type != IOMAP_IN_MEM) ||
(srcmap->flags & IOMAP_F_NEW) ||
pos >= i_size_read(iter->inode);
}
@@ -583,16 +583,26 @@ iomap_write_failed(struct inode *inode, loff_t pos, unsigned len)
pos + len - 1);
}
-static int iomap_read_folio_sync(loff_t block_start, struct folio *folio,
- size_t poff, size_t plen, const struct iomap *iomap)
+static int iomap_read_folio_sync(const struct iomap_iter *iter, loff_t block_start,
+ struct folio *folio, size_t poff, size_t plen)
{
- return iomap_bio_read_folio_sync(block_start, folio, poff, plen, iomap);
+ const struct iomap_folio_ops *folio_ops = iter->iomap.folio_ops;
+ const struct iomap *srcmap = iomap_iter_srcmap(iter);
+
+ if (folio_ops && folio_ops->read_folio_sync)
+ return folio_ops->read_folio_sync(block_start, folio,
+ poff, plen, srcmap,
+ iter->private);
+
+ /* IOMAP_IN_MEM iomaps must always handle ->read_folio_sync() */
+ WARN_ON_ONCE(iter->iomap.type == IOMAP_IN_MEM);
+
+ return iomap_bio_read_folio_sync(block_start, folio, poff, plen, srcmap);
}
static int __iomap_write_begin(const struct iomap_iter *iter, loff_t pos,
size_t len, struct folio *folio)
{
- const struct iomap *srcmap = iomap_iter_srcmap(iter);
struct iomap_folio_state *ifs;
loff_t block_size = i_blocksize(iter->inode);
loff_t block_start = round_down(pos, block_size);
@@ -640,8 +650,8 @@ static int __iomap_write_begin(const struct iomap_iter *iter, loff_t pos,
if (iter->flags & IOMAP_NOWAIT)
return -EAGAIN;
- status = iomap_read_folio_sync(block_start, folio,
- poff, plen, srcmap);
+ status = iomap_read_folio_sync(iter, block_start, folio,
+ poff, plen);
if (status)
return status;
}
diff --git a/include/linux/iomap.h b/include/linux/iomap.h
index dbbf217eb03f..e748aeebe1a5 100644
--- a/include/linux/iomap.h
+++ b/include/linux/iomap.h
@@ -175,6 +175,16 @@ struct iomap_folio_ops {
* locked by the iomap code.
*/
bool (*iomap_valid)(struct inode *inode, const struct iomap *iomap);
+
+ /*
+ * Required for IOMAP_IN_MEM iomaps. Otherwise optional if the caller
+ * wishes to handle reading in a folio.
+ *
+ * The read must be done synchronously.
+ */
+ int (*read_folio_sync)(loff_t block_start, struct folio *folio,
+ size_t off, size_t len, const struct iomap *iomap,
+ void *private);
};
/*
--
2.47.1
