Lines Matching defs:discard
111 * Recognised only if "feature-discard" is present in backend xenbus info.
112 * The "feature-discard" node contains a boolean indicating whether trim
113 * (ATA) or unmap (SCSI) - conviently called discard requests are likely
114 * to succeed or fail. Either way, a discard request
117 * or not it is worthwhile for the frontend to attempt discard requests.
119 * create the "feature-discard" node!
122 * extents to be erased. However, discard does not guarantee that the blocks
127 * sector index to begin discard operations at and nr_sectors as the number of
137 * further optimize the discard functionality:
138 * 'discard-alignment' - Devices that support discard functionality may
140 * logical block size. The discard-alignment parameter indicates how many bytes
143 * 'discard-granularity' - Devices that support discard functionality may
145 * size. The discard-granularity parameter indicates the size of the internal
147 * discard-granularity will be set to match the device's physical block size.
148 * 'discard-secure' - All copies of the discarded sectors (potentially created
207 #define BLKIF_DISCARD_SECURE (1<<0) /* ignored if discard-secure=0 */
210 uint32_t _pad2; /* offsetof(blkif_req..,u.discard.id)==8*/
249 struct blkif_request_discard discard;