Merge tag 'for-linus-20190329' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:
 "Small set of fixes that should go into this series. This contains:

   - compat signal mask fix for io_uring (Arnd)

   - EAGAIN corner case for direct vs buffered writes for io_uring
     (Roman)

   - NVMe pull request from Christoph with various little fixes

   - sbitmap ws_active fix, which caused a perf regression for shared
     tags (me)

   - sbitmap bit ordering fix (Ming)

   - libata on-stack DMA fix (Raymond)"

* tag 'for-linus-20190329' of git://git.kernel.dk/linux-block:
  nvmet: fix error flow during ns enable
  nvmet: fix building bvec from sg list
  nvme-multipath: relax ANA state check
  nvme-tcp: fix an endianess miss-annotation
  libata: fix using DMA buffers on stack
  io_uring: offload write to async worker in case of -EAGAIN
  sbitmap: order READ/WRITE freed instance and setting clear bit
  blk-mq: fix sbitmap ws_active for shared tags
  io_uring: fix big-endian compat signal mask handling
  blk-mq: update comment for blk_mq_hctx_has_pending()
  blk-mq: use blk_mq_put_driver_tag() to put tag

Author: torvalds

block/blk-flush.c

@@ -220,7 +220,7 @@ static void flush_end_io(struct request *flush_rq, blk_status_t error)
 		blk_mq_tag_set_rq(hctx, flush_rq->tag, fq->orig_rq);
 		flush_rq->tag = -1;
 	} else {
-		blk_mq_put_driver_tag_hctx(hctx, flush_rq);
+		blk_mq_put_driver_tag(flush_rq);
 		flush_rq->internal_tag = -1;
 	}
 
@@ -324,7 +324,7 @@ static void mq_flush_data_end_io(struct request *rq, blk_status_t error)
 
 	if (q->elevator) {
 		WARN_ON(rq->tag < 0);
-		blk_mq_put_driver_tag_hctx(hctx, rq);
+		blk_mq_put_driver_tag(rq);
 	}
 
 	/*

block/blk-mq.c

@@ -59,7 +59,8 @@ static int blk_mq_poll_stats_bkt(const struct request *rq)
 }
 
 /*
- * Check if any of the ctx's have pending work in this hardware queue
+ * Check if any of the ctx, dispatch list or elevator
+ * have pending work in this hardware queue.
  */
 static bool blk_mq_hctx_has_pending(struct blk_mq_hw_ctx *hctx)
 {
@@ -1071,7 +1072,13 @@ static int blk_mq_dispatch_wake(wait_queue_entry_t *wait, unsigned mode,
 	hctx = container_of(wait, struct blk_mq_hw_ctx, dispatch_wait);
 
 	spin_lock(&hctx->dispatch_wait_lock);
-	list_del_init(&wait->entry);
+	if (!list_empty(&wait->entry)) {
+		struct sbitmap_queue *sbq;
+
+		list_del_init(&wait->entry);
+		sbq = &hctx->tags->bitmap_tags;
+		atomic_dec(&sbq->ws_active);
+	}
 	spin_unlock(&hctx->dispatch_wait_lock);
 
 	blk_mq_run_hw_queue(hctx, true);
@@ -1087,6 +1094,7 @@ static int blk_mq_dispatch_wake(wait_queue_entry_t *wait, unsigned mode,
 static bool blk_mq_mark_tag_wait(struct blk_mq_hw_ctx *hctx,
 				 struct request *rq)
 {
+	struct sbitmap_queue *sbq = &hctx->tags->bitmap_tags;
 	struct wait_queue_head *wq;
 	wait_queue_entry_t *wait;
 	bool ret;
@@ -1109,7 +1117,7 @@ static bool blk_mq_mark_tag_wait(struct blk_mq_hw_ctx *hctx,
 	if (!list_empty_careful(&wait->entry))
 		return false;
 
-	wq = &bt_wait_ptr(&hctx->tags->bitmap_tags, hctx)->wait;
+	wq = &bt_wait_ptr(sbq, hctx)->wait;
 
 	spin_lock_irq(&wq->lock);
 	spin_lock(&hctx->dispatch_wait_lock);
@@ -1119,6 +1127,7 @@ static bool blk_mq_mark_tag_wait(struct blk_mq_hw_ctx *hctx,
 		return false;
 	}
 
+	atomic_inc(&sbq->ws_active);
 	wait->flags &= ~WQ_FLAG_EXCLUSIVE;
 	__add_wait_queue(wq, wait);
 
@@ -1139,6 +1148,7 @@ static bool blk_mq_mark_tag_wait(struct blk_mq_hw_ctx *hctx,
 	 * someone else gets the wakeup.
 	 */
 	list_del_init(&wait->entry);
+	atomic_dec(&sbq->ws_active);
 	spin_unlock(&hctx->dispatch_wait_lock);
 	spin_unlock_irq(&wq->lock);
 

block/blk-mq.h

@@ -224,15 +224,6 @@ static inline void __blk_mq_put_driver_tag(struct blk_mq_hw_ctx *hctx,
 	}
 }
 
-static inline void blk_mq_put_driver_tag_hctx(struct blk_mq_hw_ctx *hctx,
-				       struct request *rq)
-{
-	if (rq->tag == -1 || rq->internal_tag == -1)
-		return;
-
-	__blk_mq_put_driver_tag(hctx, rq);
-}
-
 static inline void blk_mq_put_driver_tag(struct request *rq)
 {
 	if (rq->tag == -1 || rq->internal_tag == -1)

drivers/ata/libata-zpodd.c

@@ -52,38 +52,52 @@ static int eject_tray(struct ata_device *dev)
 /* Per the spec, only slot type and drawer type ODD can be supported */
 static enum odd_mech_type zpodd_get_mech_type(struct ata_device *dev)
 {
-	char buf[16];
+	char *buf;
 	unsigned int ret;
-	struct rm_feature_desc *desc = (void *)(buf + 8);
+	struct rm_feature_desc *desc;
 	struct ata_taskfile tf;
 	static const char cdb[] = {  GPCMD_GET_CONFIGURATION,
 			2,      /* only 1 feature descriptor requested */
 			0, 3,   /* 3, removable medium feature */
 			0, 0, 0,/* reserved */
-			0, sizeof(buf),
+			0, 16,
 			0, 0, 0,
 	};
 
+	buf = kzalloc(16, GFP_KERNEL);
+	if (!buf)
+		return ODD_MECH_TYPE_UNSUPPORTED;
+	desc = (void *)(buf + 8);
+
 	ata_tf_init(dev, &tf);
 	tf.flags = ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
 	tf.command = ATA_CMD_PACKET;
 	tf.protocol = ATAPI_PROT_PIO;
-	tf.lbam = sizeof(buf);
+	tf.lbam = 16;
 
 	ret = ata_exec_internal(dev, &tf, cdb, DMA_FROM_DEVICE,
-				buf, sizeof(buf), 0);
-	if (ret)
+				buf, 16, 0);
+	if (ret) {
+		kfree(buf);
 		return ODD_MECH_TYPE_UNSUPPORTED;
+	}
 
-	if (be16_to_cpu(desc->feature_code) != 3)
+	if (be16_to_cpu(desc->feature_code) != 3) {
+		kfree(buf);
 		return ODD_MECH_TYPE_UNSUPPORTED;
+	}
 
-	if (desc->mech_type == 0 && desc->load == 0 && desc->eject == 1)
+	if (desc->mech_type == 0 && desc->load == 0 && desc->eject == 1) {
+		kfree(buf);
 		return ODD_MECH_TYPE_SLOT;
-	else if (desc->mech_type == 1 && desc->load == 0 && desc->eject == 1)
+	} else if (desc->mech_type == 1 && desc->load == 0 &&
+		   desc->eject == 1) {
+		kfree(buf);
 		return ODD_MECH_TYPE_DRAWER;
-	else
+	} else {
+		kfree(buf);
 		return ODD_MECH_TYPE_UNSUPPORTED;
+	}
 }
 
 /* Test if ODD is zero power ready by sense code */

drivers/nvme/host/multipath.c

@@ -404,15 +404,12 @@ static inline bool nvme_state_is_live(enum nvme_ana_state state)
 static void nvme_update_ns_ana_state(struct nvme_ana_group_desc *desc,
 		struct nvme_ns *ns)
 {
-	enum nvme_ana_state old;
-
 	mutex_lock(&ns->head->lock);
-	old = ns->ana_state;
 	ns->ana_grpid = le32_to_cpu(desc->grpid);
 	ns->ana_state = desc->state;
 	clear_bit(NVME_NS_ANA_PENDING, &ns->flags);
 
-	if (nvme_state_is_live(ns->ana_state) && !nvme_state_is_live(old))
+	if (nvme_state_is_live(ns->ana_state))
 		nvme_mpath_set_live(ns);
 	mutex_unlock(&ns->head->lock);
 }

drivers/nvme/host/tcp.c

@@ -627,7 +627,7 @@ static int nvme_tcp_recv_pdu(struct nvme_tcp_queue *queue, struct sk_buff *skb,
 	return ret;
 }
 
-static inline void nvme_tcp_end_request(struct request *rq, __le16 status)
+static inline void nvme_tcp_end_request(struct request *rq, u16 status)
 {
 	union nvme_result res = {};
 

drivers/nvme/target/core.c

@@ -509,7 +509,7 @@ int nvmet_ns_enable(struct nvmet_ns *ns)
 
 	ret = nvmet_p2pmem_ns_enable(ns);
 	if (ret)
-		goto out_unlock;
+		goto out_dev_disable;
 
 	list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry)
 		nvmet_p2pmem_ns_add_p2p(ctrl, ns);
@@ -550,7 +550,7 @@ int nvmet_ns_enable(struct nvmet_ns *ns)
 out_dev_put:
 	list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry)
 		pci_dev_put(radix_tree_delete(&ctrl->p2p_ns_map, ns->nsid));
-
+out_dev_disable:
 	nvmet_ns_dev_disable(ns);
 	goto out_unlock;
 }

drivers/nvme/target/io-cmd-file.c

@@ -75,11 +75,11 @@ int nvmet_file_ns_enable(struct nvmet_ns *ns)
 	return ret;
 }
 
-static void nvmet_file_init_bvec(struct bio_vec *bv, struct sg_page_iter *iter)
+static void nvmet_file_init_bvec(struct bio_vec *bv, struct scatterlist *sg)
 {
-	bv->bv_page = sg_page_iter_page(iter);
-	bv->bv_offset = iter->sg->offset;
-	bv->bv_len = PAGE_SIZE - iter->sg->offset;
+	bv->bv_page = sg_page(sg);
+	bv->bv_offset = sg->offset;
+	bv->bv_len = sg->length;
 }
 
 static ssize_t nvmet_file_submit_bvec(struct nvmet_req *req, loff_t pos,
@@ -128,14 +128,14 @@ static void nvmet_file_io_done(struct kiocb *iocb, long ret, long ret2)
 
 static bool nvmet_file_execute_io(struct nvmet_req *req, int ki_flags)
 {
-	ssize_t nr_bvec = DIV_ROUND_UP(req->data_len, PAGE_SIZE);
-	struct sg_page_iter sg_pg_iter;
+	ssize_t nr_bvec = req->sg_cnt;
 	unsigned long bv_cnt = 0;
 	bool is_sync = false;
 	size_t len = 0, total_len = 0;
 	ssize_t ret = 0;
 	loff_t pos;
-
+	int i;
+	struct scatterlist *sg;
 
 	if (req->f.mpool_alloc && nr_bvec > NVMET_MAX_MPOOL_BVEC)
 		is_sync = true;
@@ -147,8 +147,8 @@ static bool nvmet_file_execute_io(struct nvmet_req *req, int ki_flags)
 	}
 
 	memset(&req->f.iocb, 0, sizeof(struct kiocb));
-	for_each_sg_page(req->sg, &sg_pg_iter, req->sg_cnt, 0) {
-		nvmet_file_init_bvec(&req->f.bvec[bv_cnt], &sg_pg_iter);
+	for_each_sg(req->sg, sg, req->sg_cnt, i) {
+		nvmet_file_init_bvec(&req->f.bvec[bv_cnt], sg);
 		len += req->f.bvec[bv_cnt].bv_len;
 		total_len += req->f.bvec[bv_cnt].bv_len;
 		bv_cnt++;
@@ -225,7 +225,7 @@ static void nvmet_file_submit_buffered_io(struct nvmet_req *req)
 
 static void nvmet_file_execute_rw(struct nvmet_req *req)
 {
-	ssize_t nr_bvec = DIV_ROUND_UP(req->data_len, PAGE_SIZE);
+	ssize_t nr_bvec = req->sg_cnt;
 
 	if (!req->sg_cnt || !nr_bvec) {
 		nvmet_req_complete(req, 0);

fs/io_uring.c

@@ -1022,6 +1022,8 @@ static int io_write(struct io_kiocb *req, const struct sqe_submit *s,
 
 	ret = rw_verify_area(WRITE, file, &kiocb->ki_pos, iov_count);
 	if (!ret) {
+		ssize_t ret2;
+
 		/*
 		 * Open-code file_start_write here to grab freeze protection,
 		 * which will be released by another thread in
@@ -1036,7 +1038,19 @@ static int io_write(struct io_kiocb *req, const struct sqe_submit *s,
 						SB_FREEZE_WRITE);
 		}
 		kiocb->ki_flags |= IOCB_WRITE;
-		io_rw_done(kiocb, call_write_iter(file, kiocb, &iter));
+
+		ret2 = call_write_iter(file, kiocb, &iter);
+		if (!force_nonblock || ret2 != -EAGAIN) {
+			io_rw_done(kiocb, ret2);
+		} else {
+			/*
+			 * If ->needs_lock is true, we're already in async
+			 * context.
+			 */
+			if (!s->needs_lock)
+				io_async_list_note(WRITE, req, iov_count);
+			ret = -EAGAIN;
+		}
 	}
 out_free:
 	kfree(iovec);
@@ -1968,7 +1982,15 @@ static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events,
 		return 0;
 
 	if (sig) {
-		ret = set_user_sigmask(sig, &ksigmask, &sigsaved, sigsz);
+#ifdef CONFIG_COMPAT
+		if (in_compat_syscall())
+			ret = set_compat_user_sigmask((const compat_sigset_t __user *)sig,
+						      &ksigmask, &sigsaved, sigsz);
+		else
+#endif
+			ret = set_user_sigmask(sig, &ksigmask,
+					       &sigsaved, sigsz);
+
 		if (ret)
 			return ret;
 	}

lib/sbitmap.c

@@ -591,6 +591,17 @@ EXPORT_SYMBOL_GPL(sbitmap_queue_wake_up);
 void sbitmap_queue_clear(struct sbitmap_queue *sbq, unsigned int nr,
 			 unsigned int cpu)
 {
+	/*
+	 * Once the clear bit is set, the bit may be allocated out.
+	 *
+	 * Orders READ/WRITE on the asssociated instance(such as request
+	 * of blk_mq) by this bit for avoiding race with re-allocation,
+	 * and its pair is the memory barrier implied in __sbitmap_get_word.
+	 *
+	 * One invariant is that the clear bit has to be zero when the bit
+	 * is in use.
+	 */
+	smp_mb__before_atomic();
 	sbitmap_deferred_clear_bit(&sbq->sb, nr);
 
 	/*