netfs: Finish off rename of netfs_read_request to netfs_io_request

Adjust helper function names and comments after mass rename of
struct netfs_read_*request to struct netfs_io_*request.

Changes
=======
ver #2)
 - Make the changes in the docs also.
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com

Link: https://lore.kernel.org/r/164622992433.3564931.6684311087845150271.stgit@warthog.procyon.org.uk/ # v1
Link: https://lore.kernel.org/r/164678196111.1200972.5001114956865989528.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/164692892567.2099075.13895804222087028813.stgit@warthog.procyon.org.uk/ # v3

Documentation/filesystems/netfs_library.rst

@@ -250,7 +250,7 @@ through which it can issue requests and negotiate::
 		int (*begin_cache_operation)(struct netfs_io_request *rreq);
 		void (*expand_readahead)(struct netfs_io_request *rreq);
 		bool (*clamp_length)(struct netfs_io_subrequest *subreq);
-		void (*issue_op)(struct netfs_io_subrequest *subreq);
+		void (*issue_read)(struct netfs_io_subrequest *subreq);
 		bool (*is_still_valid)(struct netfs_io_request *rreq);
 		int (*check_write_begin)(struct file *file, loff_t pos, unsigned len,
 					 struct folio *folio, void **_fsdata);
@@ -305,7 +305,7 @@ The operations are as follows:
 
    This should return 0 on success and an error code on error.
 
- * ``issue_op()``
+ * ``issue_read()``
 
    [Required] The helpers use this to dispatch a subrequest to the server for
    reading.  In the subrequest, ->start, ->len and ->transferred indicate what

fs/9p/vfs_addr.c

@@ -28,10 +28,10 @@
 #include "fid.h"
 
 /**
- * v9fs_req_issue_op - Issue a read from 9P
+ * v9fs_issue_read - Issue a read from 9P
  * @subreq: The read to make
  */
-static void v9fs_req_issue_op(struct netfs_io_subrequest *subreq)
+static void v9fs_issue_read(struct netfs_io_subrequest *subreq)
 {
 	struct netfs_io_request *rreq = subreq->rreq;
 	struct p9_fid *fid = rreq->netfs_priv;
@@ -106,7 +106,7 @@ static const struct netfs_request_ops v9fs_req_ops = {
 	.init_request		= v9fs_init_request,
 	.is_cache_enabled	= v9fs_is_cache_enabled,
 	.begin_cache_operation	= v9fs_begin_cache_operation,
-	.issue_op		= v9fs_req_issue_op,
+	.issue_read		= v9fs_issue_read,
 	.cleanup		= v9fs_req_cleanup,
 };
 

fs/afs/file.c

@@ -310,7 +310,7 @@ int afs_fetch_data(struct afs_vnode *vnode, struct afs_read *req)
 	return afs_do_sync_operation(op);
 }
 
-static void afs_req_issue_op(struct netfs_io_subrequest *subreq)
+static void afs_issue_read(struct netfs_io_subrequest *subreq)
 {
 	struct afs_vnode *vnode = AFS_FS_I(subreq->rreq->inode);
 	struct afs_read *fsreq;
@@ -401,7 +401,7 @@ const struct netfs_request_ops afs_req_ops = {
 	.is_cache_enabled	= afs_is_cache_enabled,
 	.begin_cache_operation	= afs_begin_cache_operation,
 	.check_write_begin	= afs_check_write_begin,
-	.issue_op		= afs_req_issue_op,
+	.issue_read		= afs_issue_read,
 	.cleanup		= afs_priv_cleanup,
 };
 

fs/cachefiles/io.c

@@ -406,7 +406,7 @@ static enum netfs_io_source cachefiles_prepare_read(struct netfs_io_subrequest *
 	}
 
 	if (test_bit(FSCACHE_COOKIE_NO_DATA_TO_READ, &cookie->flags)) {
-		__set_bit(NETFS_SREQ_WRITE_TO_CACHE, &subreq->flags);
+		__set_bit(NETFS_SREQ_COPY_TO_CACHE, &subreq->flags);
 		why = cachefiles_trace_read_no_data;
 		goto out_no_object;
 	}
@@ -475,7 +475,7 @@ static enum netfs_io_source cachefiles_prepare_read(struct netfs_io_subrequest *
 	goto out;
 
 download_and_store:
-	__set_bit(NETFS_SREQ_WRITE_TO_CACHE, &subreq->flags);
+	__set_bit(NETFS_SREQ_COPY_TO_CACHE, &subreq->flags);
 out:
 	cachefiles_end_secure(cache, saved_cred);
 out_no_object:

fs/ceph/addr.c

@@ -259,7 +259,7 @@ static bool ceph_netfs_issue_op_inline(struct netfs_io_subrequest *subreq)
 	size_t len;
 
 	__set_bit(NETFS_SREQ_CLEAR_TAIL, &subreq->flags);
-	__clear_bit(NETFS_SREQ_WRITE_TO_CACHE, &subreq->flags);
+	__clear_bit(NETFS_SREQ_COPY_TO_CACHE, &subreq->flags);
 
 	if (subreq->start >= inode->i_size)
 		goto out;
@@ -298,7 +298,7 @@ static bool ceph_netfs_issue_op_inline(struct netfs_io_subrequest *subreq)
 	return true;
 }
 
-static void ceph_netfs_issue_op(struct netfs_io_subrequest *subreq)
+static void ceph_netfs_issue_read(struct netfs_io_subrequest *subreq)
 {
 	struct netfs_io_request *rreq = subreq->rreq;
 	struct inode *inode = rreq->inode;
@@ -367,7 +367,7 @@ static void ceph_readahead_cleanup(struct address_space *mapping, void *priv)
 static const struct netfs_request_ops ceph_netfs_read_ops = {
 	.is_cache_enabled	= ceph_is_cache_enabled,
 	.begin_cache_operation	= ceph_begin_cache_operation,
-	.issue_op		= ceph_netfs_issue_op,
+	.issue_read		= ceph_netfs_issue_read,
 	.expand_readahead	= ceph_netfs_expand_readahead,
 	.clamp_length		= ceph_netfs_clamp_length,
 	.check_write_begin	= ceph_netfs_check_write_begin,

include/linux/netfs.h

@@ -131,7 +131,7 @@ struct netfs_cache_resources {
  * Descriptor for a single component subrequest.
  */
 struct netfs_io_subrequest {
-	struct netfs_io_request *rreq;	/* Supervising read request */
+	struct netfs_io_request *rreq;		/* Supervising I/O request */
 	struct list_head	rreq_link;	/* Link in rreq->subrequests */
 	loff_t			start;		/* Where to start the I/O */
 	size_t			len;		/* Size of the I/O */
@@ -139,29 +139,29 @@ struct netfs_io_subrequest {
 	refcount_t		usage;
 	short			error;		/* 0 or error that occurred */
 	unsigned short		debug_index;	/* Index in list (for debugging output) */
-	enum netfs_io_source	source;		/* Where to read from */
+	enum netfs_io_source	source;		/* Where to read from/write to */
 	unsigned long		flags;
-#define NETFS_SREQ_WRITE_TO_CACHE	0	/* Set if should write to cache */
+#define NETFS_SREQ_COPY_TO_CACHE	0	/* Set if should copy the data to the cache */
 #define NETFS_SREQ_CLEAR_TAIL		1	/* Set if the rest of the read should be cleared */
-#define NETFS_SREQ_SHORT_READ		2	/* Set if there was a short read from the cache */
+#define NETFS_SREQ_SHORT_IO		2	/* Set if the I/O was short */
 #define NETFS_SREQ_SEEK_DATA_READ	3	/* Set if ->read() should SEEK_DATA first */
 #define NETFS_SREQ_NO_PROGRESS		4	/* Set if we didn't manage to read any data */
 };
 
 /*
- * Descriptor for a read helper request.  This is used to make multiple I/O
- * requests on a variety of sources and then stitch the result together.
+ * Descriptor for an I/O helper request.  This is used to make multiple I/O
+ * operations to a variety of data stores and then stitch the result together.
  */
 struct netfs_io_request {
 	struct work_struct	work;
 	struct inode		*inode;		/* The file being accessed */
 	struct address_space	*mapping;	/* The mapping being accessed */
 	struct netfs_cache_resources cache_resources;
-	struct list_head	subrequests;	/* Requests to fetch I/O from disk or net */
+	struct list_head	subrequests;	/* Contributory I/O operations */
 	void			*netfs_priv;	/* Private data for the netfs */
 	unsigned int		debug_id;
-	atomic_t		nr_outstanding;	/* Number of read ops in progress */
-	atomic_t		nr_copy_ops;	/* Number of write ops in progress */
+	atomic_t		nr_outstanding;	/* Number of ops in progress */
+	atomic_t		nr_copy_ops;	/* Number of copy-to-cache ops in progress */
 	size_t			submitted;	/* Amount submitted for I/O so far */
 	size_t			len;		/* Length of the request */
 	short			error;		/* 0 or error that occurred */
@@ -171,7 +171,7 @@ struct netfs_io_request {
 	refcount_t		usage;
 	unsigned long		flags;
 #define NETFS_RREQ_INCOMPLETE_IO	0	/* Some ioreqs terminated short or with error */
-#define NETFS_RREQ_WRITE_TO_CACHE	1	/* Need to write to the cache */
+#define NETFS_RREQ_COPY_TO_CACHE	1	/* Need to write to the cache */
 #define NETFS_RREQ_NO_UNLOCK_FOLIO	2	/* Don't unlock no_unlock_folio on completion */
 #define NETFS_RREQ_DONT_UNLOCK_FOLIOS	3	/* Don't unlock the folios on completion */
 #define NETFS_RREQ_FAILED		4	/* The request failed */
@@ -188,7 +188,7 @@ struct netfs_request_ops {
 	int (*begin_cache_operation)(struct netfs_io_request *rreq);
 	void (*expand_readahead)(struct netfs_io_request *rreq);
 	bool (*clamp_length)(struct netfs_io_subrequest *subreq);
-	void (*issue_op)(struct netfs_io_subrequest *subreq);
+	void (*issue_read)(struct netfs_io_subrequest *subreq);
 	bool (*is_still_valid)(struct netfs_io_request *rreq);
 	int (*check_write_begin)(struct file *file, loff_t pos, unsigned len,
 				 struct folio *folio, void **_fsdata);