interface: rename of trim to discard in blkif.h

Just a simple sed s/trim/discard/. We are ignoring the comments
which are incorrect.

The reason for the name change is that TRIM is specific to ATA
while the operation can be done on top of SCSI interfaces too.
Hence the rename to something more generic.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Committed-by: Keir Fraser <keir@xen.org>

diff --git a/xen/include/public/io/blkif.h b/xen/include/public/io/blkif.h
index 001df71b1bd98f46edf92ff9eddc5857b2147a3c..c10bdad98b273ceb064e4c20209b32990a869438 100644 (file)
--- a/xen/include/public/io/blkif.h
+++ b/xen/include/public/io/blkif.h
@@ -82,25 +82,25 @@
  */
 #define BLKIF_OP_RESERVED_1        4
 /*
- * Recognised only if "feature-trim" is present in backend xenbus info.
- * The "feature-trim" node contains a boolean indicating whether trim
- * requests are likely to succeed or fail. Either way, a trim request
+ * Recognised only if "feature-discard" is present in backend xenbus info.
+ * The "feature-discard" node contains a boolean indicating whether discard
+ * requests are likely to succeed or fail. Either way, a discard request
  * may fail at any time with BLKIF_RSP_EOPNOTSUPP if it is unsupported by
  * the underlying block-device hardware. The boolean simply indicates whether
- * or not it is worthwhile for the frontend to attempt trim requests.
- * If a backend does not recognise BLKIF_OP_TRIM, it should *not*
- * create the "feature-trim" node!
+ * or not it is worthwhile for the frontend to attempt discard requests.
+ * If a backend does not recognise BLKIF_OP_DISCARD, it should *not*
+ * create the "feature-discard" node!
  * 
- * Trim operation is a request for the underlying block device to mark
- * extents to be erased. Trim operations are passed with sector_number as the
- * sector index to begin trim operations at and nr_sectors as the number of
- * sectors to be trimmed. The specified sectors should be trimmed if the
- * underlying block device supports trim operations, or a BLKIF_RSP_EOPNOTSUPP
- * should be returned. More information about trim operations at:
+ * Discard operation is a request for the underlying block device to mark
+ * extents to be erased. Discard operations are passed with sector_number as the
+ * sector index to begin discard operations at and nr_sectors as the number of
+ * sectors to be discarded. The specified sectors should be discarded if the
+ * underlying block device supports discard operations, or a BLKIF_RSP_EOPNOTSUPP
+ * should be returned. More information about discard operations at:
  * http://t13.org/Documents/UploadedDocuments/docs2008/
  *     e07154r6-Data_Set_Management_Proposal_for_ATA-ACS2.doc
  */
-#define BLKIF_OP_TRIM              5
+#define BLKIF_OP_DISCARD           5
 
 /*
  * Maximum scatter/gather segments per request.
@@ -135,17 +135,17 @@ typedef struct blkif_request blkif_request_t;
 
 /*
  * Cast to this structure when blkif_request.operation == BLKIF_OP_TRIM
- * sizeof(struct blkif_request_trim) <= sizeof(struct blkif_request)
+ * sizeof(struct blkif_request_discard) <= sizeof(struct blkif_request)
  */
-struct blkif_request_trim {
-    uint8_t        operation;    /* BLKIF_OP_TRIM                        */
+struct blkif_request_discard {
+    uint8_t        operation;    /* BLKIF_OP_DISCARD                     */
     uint8_t        reserved;     /*                                      */
     blkif_vdev_t   handle;       /* same as for read/write requests      */
     uint64_t       id;           /* private guest value, echoed in resp  */
     blkif_sector_t sector_number;/* start sector idx on disk             */
-    uint64_t       nr_sectors;   /* number of contiguous sectors to trim */
+    uint64_t       nr_sectors;   /* number of contiguous sectors to discard*/
 };
-typedef struct blkif_request_trim blkif_request_trim_t;
+typedef struct blkif_request_discard blkif_request_discard_t;
 
 struct blkif_response {
     uint64_t        id;              /* copied from request */