mm, page_alloc: rename __GFP_WAIT to __GFP_RECLAIM

__GFP_WAIT was used to signal that the caller was in atomic context and
could not sleep.  Now it is possible to distinguish between true atomic
context and callers that are not willing to sleep.  The latter should
clear __GFP_DIRECT_RECLAIM so kswapd will still wake.  As clearing
__GFP_WAIT behaves differently, there is a risk that people will clear the
wrong flags.  This patch renames __GFP_WAIT to __GFP_RECLAIM to clearly
indicate what it does -- setting it allows all reclaim activity, clearing
them prevents it.

[akpm@linux-foundation.org: fix build]
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Christoph Lameter <cl@linux.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Vitaly Wool <vitalywool@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

block/blk-core.c

@@ -638,7 +638,7 @@ int blk_queue_enter(struct request_queue *q, gfp_t gfp)
 		if (percpu_ref_tryget_live(&q->q_usage_counter))
 			return 0;
 
-		if (!(gfp & __GFP_WAIT))
+		if (!gfpflags_allow_blocking(gfp))
 			return -EBUSY;
 
 		ret = wait_event_interruptible(q->mq_freeze_wq,
@@ -2038,7 +2038,7 @@ void generic_make_request(struct bio *bio)
 	do {
 		struct request_queue *q = bdev_get_queue(bio->bi_bdev);
 
-		if (likely(blk_queue_enter(q, __GFP_WAIT) == 0)) {
+		if (likely(blk_queue_enter(q, __GFP_DIRECT_RECLAIM) == 0)) {
 
 			q->make_request_fn(q, bio);
 

block/blk-mq.c

@@ -1186,7 +1186,7 @@ static struct request *blk_mq_map_request(struct request_queue *q,
 		ctx = blk_mq_get_ctx(q);
 		hctx = q->mq_ops->map_queue(q, ctx->cpu);
 		blk_mq_set_alloc_data(&alloc_data, q,
-				__GFP_WAIT|__GFP_HIGH, false, ctx, hctx);
+				__GFP_RECLAIM|__GFP_HIGH, false, ctx, hctx);
 		rq = __blk_mq_alloc_request(&alloc_data, rw);
 		ctx = alloc_data.ctx;
 		hctx = alloc_data.hctx;

block/scsi_ioctl.c

@@ -444,7 +444,7 @@ int sg_scsi_ioctl(struct request_queue *q, struct gendisk *disk, fmode_t mode,
 
 	}
 
-	rq = blk_get_request(q, in_len ? WRITE : READ, __GFP_WAIT);
+	rq = blk_get_request(q, in_len ? WRITE : READ, __GFP_RECLAIM);
 	if (IS_ERR(rq)) {
 		err = PTR_ERR(rq);
 		goto error_free_buffer;
@@ -495,7 +495,7 @@ int sg_scsi_ioctl(struct request_queue *q, struct gendisk *disk, fmode_t mode,
 		break;
 	}
 
-	if (bytes && blk_rq_map_kern(q, rq, buffer, bytes, __GFP_WAIT)) {
+	if (bytes && blk_rq_map_kern(q, rq, buffer, bytes, __GFP_RECLAIM)) {
 		err = DRIVER_ERROR << 24;
 		goto error;
 	}
@@ -536,7 +536,7 @@ static int __blk_send_generic(struct request_queue *q, struct gendisk *bd_disk,
 	struct request *rq;
 	int err;
 
-	rq = blk_get_request(q, WRITE, __GFP_WAIT);
+	rq = blk_get_request(q, WRITE, __GFP_RECLAIM);
 	if (IS_ERR(rq))
 		return PTR_ERR(rq);
 	blk_rq_set_block_pc(rq);

drivers/block/drbd/drbd_bitmap.c

@@ -1007,7 +1007,7 @@ static void bm_page_io_async(struct drbd_bm_aio_ctx *ctx, int page_nr) __must_ho
 	bm_set_page_unchanged(b->bm_pages[page_nr]);
 
 	if (ctx->flags & BM_AIO_COPY_PAGES) {
-		page = mempool_alloc(drbd_md_io_page_pool, __GFP_HIGHMEM|__GFP_WAIT);
+		page = mempool_alloc(drbd_md_io_page_pool, __GFP_HIGHMEM|__GFP_RECLAIM);
 		copy_highpage(page, b->bm_pages[page_nr]);
 		bm_store_page_idx(page, page_nr);
 	} else

drivers/block/mtip32xx/mtip32xx.c

@@ -173,7 +173,7 @@ static struct mtip_cmd *mtip_get_int_command(struct driver_data *dd)
 {
 	struct request *rq;
 
-	rq = blk_mq_alloc_request(dd->queue, 0, __GFP_WAIT, true);
+	rq = blk_mq_alloc_request(dd->queue, 0, __GFP_RECLAIM, true);
 	return blk_mq_rq_to_pdu(rq);
 }
 

drivers/block/paride/pd.c

@@ -723,7 +723,7 @@ static int pd_special_command(struct pd_unit *disk,
 	struct request *rq;
 	int err = 0;
 
-	rq = blk_get_request(disk->gd->queue, READ, __GFP_WAIT);
+	rq = blk_get_request(disk->gd->queue, READ, __GFP_RECLAIM);
 	if (IS_ERR(rq))
 		return PTR_ERR(rq);
 

drivers/block/pktcdvd.c

@@ -704,14 +704,14 @@ static int pkt_generic_packet(struct pktcdvd_device *pd, struct packet_command *
 	int ret = 0;
 
 	rq = blk_get_request(q, (cgc->data_direction == CGC_DATA_WRITE) ?
-			     WRITE : READ, __GFP_WAIT);
+			     WRITE : READ, __GFP_RECLAIM);
 	if (IS_ERR(rq))
 		return PTR_ERR(rq);
 	blk_rq_set_block_pc(rq);
 
 	if (cgc->buflen) {
 		ret = blk_rq_map_kern(q, rq, cgc->buffer, cgc->buflen,
-				      __GFP_WAIT);
+				      __GFP_RECLAIM);
 		if (ret)
 			goto out;
 	}

drivers/gpu/drm/i915/i915_gem.c

@@ -2216,7 +2216,7 @@ i915_gem_object_get_pages_gtt(struct drm_i915_gem_object *obj)
 	mapping = file_inode(obj->base.filp)->i_mapping;
 	gfp = mapping_gfp_mask(mapping);
 	gfp |= __GFP_NORETRY | __GFP_NOWARN;
-	gfp &= ~(__GFP_IO | __GFP_WAIT);
+	gfp &= ~(__GFP_IO | __GFP_RECLAIM);
 	sg = st->sgl;
 	st->nents = 0;
 	for (i = 0; i < page_count; i++) {

drivers/ide/ide-atapi.c

@@ -92,7 +92,7 @@ int ide_queue_pc_tail(ide_drive_t *drive, struct gendisk *disk,
 	struct request *rq;
 	int error;
 
-	rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
+	rq = blk_get_request(drive->queue, READ, __GFP_RECLAIM);
 	rq->cmd_type = REQ_TYPE_DRV_PRIV;
 	rq->special = (char *)pc;
 

drivers/ide/ide-cd.c

@@ -441,7 +441,7 @@ int ide_cd_queue_pc(ide_drive_t *drive, const unsigned char *cmd,
 		struct request *rq;
 		int error;
 
-		rq = blk_get_request(drive->queue, write, __GFP_WAIT);
+		rq = blk_get_request(drive->queue, write, __GFP_RECLAIM);
 
 		memcpy(rq->cmd, cmd, BLK_MAX_CDB);
 		rq->cmd_type = REQ_TYPE_ATA_PC;

drivers/ide/ide-cd_ioctl.c

@@ -303,7 +303,7 @@ int ide_cdrom_reset(struct cdrom_device_info *cdi)
 	struct request *rq;
 	int ret;
 
-	rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
+	rq = blk_get_request(drive->queue, READ, __GFP_RECLAIM);
 	rq->cmd_type = REQ_TYPE_DRV_PRIV;
 	rq->cmd_flags = REQ_QUIET;
 	ret = blk_execute_rq(drive->queue, cd->disk, rq, 0);

drivers/ide/ide-devsets.c

@@ -165,7 +165,7 @@ int ide_devset_execute(ide_drive_t *drive, const struct ide_devset *setting,
 	if (!(setting->flags & DS_SYNC))
 		return setting->set(drive, arg);
 
-	rq = blk_get_request(q, READ, __GFP_WAIT);
+	rq = blk_get_request(q, READ, __GFP_RECLAIM);
 	rq->cmd_type = REQ_TYPE_DRV_PRIV;
 	rq->cmd_len = 5;
 	rq->cmd[0] = REQ_DEVSET_EXEC;

drivers/ide/ide-disk.c

@@ -477,7 +477,7 @@ static int set_multcount(ide_drive_t *drive, int arg)
 	if (drive->special_flags & IDE_SFLAG_SET_MULTMODE)
 		return -EBUSY;
 
-	rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
+	rq = blk_get_request(drive->queue, READ, __GFP_RECLAIM);
 	rq->cmd_type = REQ_TYPE_ATA_TASKFILE;
 
 	drive->mult_req = arg;

drivers/ide/ide-ioctls.c

@@ -125,7 +125,7 @@ static int ide_cmd_ioctl(ide_drive_t *drive, unsigned long arg)
 	if (NULL == (void *) arg) {
 		struct request *rq;
 
-		rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
+		rq = blk_get_request(drive->queue, READ, __GFP_RECLAIM);
 		rq->cmd_type = REQ_TYPE_ATA_TASKFILE;
 		err = blk_execute_rq(drive->queue, NULL, rq, 0);
 		blk_put_request(rq);
@@ -221,7 +221,7 @@ static int generic_drive_reset(ide_drive_t *drive)
 	struct request *rq;
 	int ret = 0;
 
-	rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
+	rq = blk_get_request(drive->queue, READ, __GFP_RECLAIM);
 	rq->cmd_type = REQ_TYPE_DRV_PRIV;
 	rq->cmd_len = 1;
 	rq->cmd[0] = REQ_DRIVE_RESET;

drivers/ide/ide-park.c

@@ -31,7 +31,7 @@ static void issue_park_cmd(ide_drive_t *drive, unsigned long timeout)
 	}
 	spin_unlock_irq(&hwif->lock);
 
-	rq = blk_get_request(q, READ, __GFP_WAIT);
+	rq = blk_get_request(q, READ, __GFP_RECLAIM);
 	rq->cmd[0] = REQ_PARK_HEADS;
 	rq->cmd_len = 1;
 	rq->cmd_type = REQ_TYPE_DRV_PRIV;

drivers/ide/ide-pm.c

@@ -18,7 +18,7 @@ int generic_ide_suspend(struct device *dev, pm_message_t mesg)
 	}
 
 	memset(&rqpm, 0, sizeof(rqpm));
-	rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
+	rq = blk_get_request(drive->queue, READ, __GFP_RECLAIM);
 	rq->cmd_type = REQ_TYPE_ATA_PM_SUSPEND;
 	rq->special = &rqpm;
 	rqpm.pm_step = IDE_PM_START_SUSPEND;
@@ -88,7 +88,7 @@ int generic_ide_resume(struct device *dev)
 	}
 
 	memset(&rqpm, 0, sizeof(rqpm));
-	rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
+	rq = blk_get_request(drive->queue, READ, __GFP_RECLAIM);
 	rq->cmd_type = REQ_TYPE_ATA_PM_RESUME;
 	rq->cmd_flags |= REQ_PREEMPT;
 	rq->special = &rqpm;

drivers/ide/ide-tape.c

@@ -852,7 +852,7 @@ static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int size)
 	BUG_ON(cmd != REQ_IDETAPE_READ && cmd != REQ_IDETAPE_WRITE);
 	BUG_ON(size < 0 || size % tape->blk_size);
 
-	rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
+	rq = blk_get_request(drive->queue, READ, __GFP_RECLAIM);
 	rq->cmd_type = REQ_TYPE_DRV_PRIV;
 	rq->cmd[13] = cmd;
 	rq->rq_disk = tape->disk;
@@ -860,7 +860,7 @@ static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int size)
 
 	if (size) {
 		ret = blk_rq_map_kern(drive->queue, rq, tape->buf, size,
-				      __GFP_WAIT);
+				      __GFP_RECLAIM);
 		if (ret)
 			goto out_put;
 	}

drivers/ide/ide-taskfile.c

@@ -430,7 +430,7 @@ int ide_raw_taskfile(ide_drive_t *drive, struct ide_cmd *cmd, u8 *buf,
 	int error;
 	int rw = !(cmd->tf_flags & IDE_TFLAG_WRITE) ? READ : WRITE;
 
-	rq = blk_get_request(drive->queue, rw, __GFP_WAIT);
+	rq = blk_get_request(drive->queue, rw, __GFP_RECLAIM);
 	rq->cmd_type = REQ_TYPE_ATA_TASKFILE;
 
 	/*
@@ -441,7 +441,7 @@ int ide_raw_taskfile(ide_drive_t *drive, struct ide_cmd *cmd, u8 *buf,
 	 */
 	if (nsect) {
 		error = blk_rq_map_kern(drive->queue, rq, buf,
-					nsect * SECTOR_SIZE, __GFP_WAIT);
+					nsect * SECTOR_SIZE, __GFP_RECLAIM);
 		if (error)
 			goto put_req;
 	}

drivers/infiniband/hw/qib/qib_init.c

@@ -1680,7 +1680,7 @@ int qib_setup_eagerbufs(struct qib_ctxtdata *rcd)
 	 * heavy filesystem activity makes these fail, and we can
 	 * use compound pages.
 	 */
-	gfp_flags = __GFP_WAIT | __GFP_IO | __GFP_COMP;
+	gfp_flags = __GFP_RECLAIM | __GFP_IO | __GFP_COMP;
 
 	egrcnt = rcd->rcvegrcnt;
 	egroff = rcd->rcvegr_tid_base;

drivers/misc/vmw_balloon.c

@@ -75,7 +75,7 @@ MODULE_LICENSE("GPL");
 
 /*
  * Use __GFP_HIGHMEM to allow pages from HIGHMEM zone. We don't
- * allow wait (__GFP_WAIT) for NOSLEEP page allocations. Use
+ * allow wait (__GFP_RECLAIM) for NOSLEEP page allocations. Use
  * __GFP_NOWARN, to suppress page allocation failure warnings.
  */
 #define VMW_PAGE_ALLOC_NOSLEEP		(__GFP_HIGHMEM|__GFP_NOWARN)