[v2,06/53] netfs: Pass a flag to ->prepare_write() to say if there's no alloc'd space

Commit Message

David Howells Oct. 22, 2021, 7 p.m. UTC

Pass a flag to ->prepare_write() to indicate if there's definitely no
space allocated in the cache yet (for instance if we've already checked as
we were asked to do a read).

Signed-off-by: David Howells <[e-mail]>
cc: [e-mail]
---

 fs/cachefiles_old/io.c |    3 ++-
 fs/netfs/read_helper.c |    2 +-
 include/linux/netfs.h  |    3 ++-
 3 files changed, 5 insertions(+), 3 deletions(-)

Patch

diff --git a/fs/cachefiles_old/io.c b/fs/cachefiles_old/io.c
index 5ead97de4bb7..eab8641de994 100644
--- a/fs/cachefiles_old/io.c
+++ b/fs/cachefiles_old/io.c
@@ -341,7 +341,8 @@  static enum netfs_read_source cachefiles_prepare_read(struct netfs_read_subreque
  * Prepare for a write to occur.
  */
 static int cachefiles_prepare_write(struct netfs_cache_resources *cres,
-				    loff_t *_start, size_t *_len, loff_t i_size)
+				    loff_t *_start, size_t *_len, loff_t i_size,
+				    bool no_space_allocated_yet)
 {
 	loff_t start = *_start;
 	size_t len = *_len, down;
diff --git a/fs/netfs/read_helper.c b/fs/netfs/read_helper.c
index dfc60c79a9f3..80f8e334371d 100644
--- a/fs/netfs/read_helper.c
+++ b/fs/netfs/read_helper.c
@@ -323,7 +323,7 @@  static void netfs_rreq_do_write_to_cache(struct netfs_read_request *rreq)
 		}
 
 		ret = cres->ops->prepare_write(cres, &subreq->start, &subreq->len,
-					       rreq->i_size);
+					       rreq->i_size, true);
 		if (ret < 0) {
 			trace_netfs_failure(rreq, subreq, ret, netfs_fail_prepare_write);
 			trace_netfs_sreq(subreq, netfs_sreq_trace_write_skip);
diff --git a/include/linux/netfs.h b/include/linux/netfs.h
index 014fb502fd91..99137486d351 100644
--- a/include/linux/netfs.h
+++ b/include/linux/netfs.h
@@ -220,7 +220,8 @@  struct netfs_cache_ops {
 	 * actually do.
 	 */
 	int (*prepare_write)(struct netfs_cache_resources *cres,
-			     loff_t *_start, size_t *_len, loff_t i_size);
+			     loff_t *_start, size_t *_len, loff_t i_size,
+			     bool no_space_allocated_yet);
 
 	/* Prepare a write operation for the fallback fscache API, working out
 	 * whether we can cache a page or not.