[pull] master from torvalds:master

arch/sparc/lib/csum_copy.S

@@ -71,7 +71,7 @@
 FUNC_NAME:		/* %o0=src, %o1=dst, %o2=len */
 	LOAD(prefetch, %o0 + 0x000, #n_reads)
 	xor		%o0, %o1, %g1
-	mov		1, %o3
+	mov		-1, %o3
 	clr		%o4
 	andcc		%g1, 0x3, %g0
 	bne,pn		%icc, 95f

drivers/scsi/megaraid/megaraid_sas_base.c

@@ -37,7 +37,6 @@
 #include <linux/poll.h>
 #include <linux/vmalloc.h>
 #include <linux/irq_poll.h>
-#include <linux/blk-mq-pci.h>
 
 #include <scsi/scsi.h>
 #include <scsi/scsi_cmnd.h>
@@ -114,10 +113,6 @@ unsigned int enable_sdev_max_qd;
 module_param(enable_sdev_max_qd, int, 0444);
 MODULE_PARM_DESC(enable_sdev_max_qd, "Enable sdev max qd as can_queue. Default: 0");
 
-int host_tagset_enable = 1;
-module_param(host_tagset_enable, int, 0444);
-MODULE_PARM_DESC(host_tagset_enable, "Shared host tagset enable/disable Default: enable(1)");
-
 MODULE_LICENSE("GPL");
 MODULE_VERSION(MEGASAS_VERSION);
 MODULE_AUTHOR("megaraidlinux.pdl@broadcom.com");
@@ -3124,19 +3119,6 @@ megasas_bios_param(struct scsi_device *sdev, struct block_device *bdev,
 	return 0;
 }
 
-static int megasas_map_queues(struct Scsi_Host *shost)
-{
-	struct megasas_instance *instance;
-
-	instance = (struct megasas_instance *)shost->hostdata;
-
-	if (shost->nr_hw_queues == 1)
-		return 0;
-
-	return blk_mq_pci_map_queues(&shost->tag_set.map[HCTX_TYPE_DEFAULT],
-			instance->pdev, instance->low_latency_index_start);
-}
-
 static void megasas_aen_polling(struct work_struct *work);
 
 /**
@@ -3445,7 +3427,6 @@ static struct scsi_host_template megasas_template = {
 	.eh_timed_out = megasas_reset_timer,
 	.shost_attrs = megaraid_host_attrs,
 	.bios_param = megasas_bios_param,
-	.map_queues = megasas_map_queues,
 	.change_queue_depth = scsi_change_queue_depth,
 	.max_segment_size = 0xffffffff,
 };
@@ -6827,26 +6808,6 @@ static int megasas_io_attach(struct megasas_instance *instance)
 	host->max_lun = MEGASAS_MAX_LUN;
 	host->max_cmd_len = 16;
 
-	/* Use shared host tagset only for fusion adaptors
-	 * if there are managed interrupts (smp affinity enabled case).
-	 * Single msix_vectors in kdump, so shared host tag is also disabled.
-	 */
-
-	host->host_tagset = 0;
-	host->nr_hw_queues = 1;
-
-	if ((instance->adapter_type != MFI_SERIES) &&
-		(instance->msix_vectors > instance->low_latency_index_start) &&
-		host_tagset_enable &&
-		instance->smp_affinity_enable) {
-		host->host_tagset = 1;
-		host->nr_hw_queues = instance->msix_vectors -
-			instance->low_latency_index_start;
-	}
-
-	dev_info(&instance->pdev->dev,
-		"Max firmware commands: %d shared with nr_hw_queues = %d\n",
-		instance->max_fw_cmds, host->nr_hw_queues);
 	/*
 	 * Notify the mid-layer about the new controller
 	 */

drivers/scsi/megaraid/megaraid_sas_fusion.c

@@ -359,29 +359,24 @@ megasas_get_msix_index(struct megasas_instance *instance,
 {
 	int sdev_busy;
 
-	/* TBD - if sml remove device_busy in future, driver
-	 * should track counter in internal structure.
-	 */
-	sdev_busy = atomic_read(&scmd->device->device_busy);
+	/* nr_hw_queue = 1 for MegaRAID */
+	struct blk_mq_hw_ctx *hctx =
+		scmd->device->request_queue->queue_hw_ctx[0];
+
+	sdev_busy = atomic_read(&hctx->nr_active);
 
 	if (instance->perf_mode == MR_BALANCED_PERF_MODE &&
-	    sdev_busy > (data_arms * MR_DEVICE_HIGH_IOPS_DEPTH)) {
+	    sdev_busy > (data_arms * MR_DEVICE_HIGH_IOPS_DEPTH))
 		cmd->request_desc->SCSIIO.MSIxIndex =
 			mega_mod64((atomic64_add_return(1, &instance->high_iops_outstanding) /
 					MR_HIGH_IOPS_BATCH_COUNT), instance->low_latency_index_start);
-	} else if (instance->msix_load_balance) {
+	else if (instance->msix_load_balance)
 		cmd->request_desc->SCSIIO.MSIxIndex =
 			(mega_mod64(atomic64_add_return(1, &instance->total_io_count),
 				instance->msix_vectors));
-	} else if (instance->host->nr_hw_queues > 1) {
-		u32 tag = blk_mq_unique_tag(scmd->request);
-
-		cmd->request_desc->SCSIIO.MSIxIndex = blk_mq_unique_tag_to_hwq(tag) +
-			instance->low_latency_index_start;
-	} else {
+	else
 		cmd->request_desc->SCSIIO.MSIxIndex =
 			instance->reply_map[raw_smp_processor_id()];
-	}
 }
 
 /**
@@ -961,6 +956,9 @@ megasas_alloc_cmds_fusion(struct megasas_instance *instance)
 	if (megasas_alloc_cmdlist_fusion(instance))
 		goto fail_exit;
 
+	dev_info(&instance->pdev->dev, "Configured max firmware commands: %d\n",
+		 instance->max_fw_cmds);
+
 	/* The first 256 bytes (SMID 0) is not used. Don't add to the cmd list */
 	io_req_base = fusion->io_request_frames + MEGA_MPI2_RAID_DEFAULT_IO_FRAME_SIZE;
 	io_req_base_phys = fusion->io_request_frames_phys + MEGA_MPI2_RAID_DEFAULT_IO_FRAME_SIZE;
@@ -1104,9 +1102,8 @@ megasas_ioc_init_fusion(struct megasas_instance *instance)
 		MR_HIGH_IOPS_QUEUE_COUNT) && cur_intr_coalescing)
 		instance->perf_mode = MR_BALANCED_PERF_MODE;
 
-	dev_info(&instance->pdev->dev, "Performance mode :%s (latency index = %d)\n",
-		MEGASAS_PERF_MODE_2STR(instance->perf_mode),
-		instance->low_latency_index_start);
+	dev_info(&instance->pdev->dev, "Performance mode :%s\n",
+		MEGASAS_PERF_MODE_2STR(instance->perf_mode));
 
 	instance->fw_sync_cache_support = (scratch_pad_1 &
 		MR_CAN_HANDLE_SYNC_CACHE_OFFSET) ? 1 : 0;

fs/seq_file.c

@@ -168,12 +168,14 @@ EXPORT_SYMBOL(seq_read);
 ssize_t seq_read_iter(struct kiocb *iocb, struct iov_iter *iter)
 {
 	struct seq_file *m = iocb->ki_filp->private_data;
-	size_t size = iov_iter_count(iter);
 	size_t copied = 0;
 	size_t n;
 	void *p;
 	int err = 0;
 
+	if (!iov_iter_count(iter))
+		return 0;
+
 	mutex_lock(&m->lock);
 
 	/*
@@ -206,36 +208,34 @@ ssize_t seq_read_iter(struct kiocb *iocb, struct iov_iter *iter)
 		if (!m->buf)
 			goto Enomem;
 	}
-	/* if not empty - flush it first */
+	// something left in the buffer - copy it out first
 	if (m->count) {
-		n = min(m->count, size);
-		if (copy_to_iter(m->buf + m->from, n, iter) != n)
-			goto Efault;
+		n = copy_to_iter(m->buf + m->from, m->count, iter);
 		m->count -= n;
 		m->from += n;
-		size -= n;
 		copied += n;
-		if (!size)
+		if (m->count)	// hadn't managed to copy everything
 			goto Done;
 	}
-	/* we need at least one record in buffer */
+	// get a non-empty record in the buffer
 	m->from = 0;
 	p = m->op->start(m, &m->index);
 	while (1) {
 		err = PTR_ERR(p);
-		if (!p || IS_ERR(p))
+		if (!p || IS_ERR(p))	// EOF or an error
 			break;
 		err = m->op->show(m, p);
-		if (err < 0)
+		if (err < 0)		// hard error
 			break;
-		if (unlikely(err))
+		if (unlikely(err))	// ->show() says "skip it"
 			m->count = 0;
-		if (unlikely(!m->count)) {
+		if (unlikely(!m->count)) { // empty record
 			p = m->op->next(m, p, &m->index);
 			continue;
 		}
-		if (m->count < m->size)
+		if (!seq_has_overflowed(m)) // got it
 			goto Fill;
+		// need a bigger buffer
 		m->op->stop(m, p);
 		kvfree(m->buf);
 		m->count = 0;
@@ -244,11 +244,14 @@ ssize_t seq_read_iter(struct kiocb *iocb, struct iov_iter *iter)
 			goto Enomem;
 		p = m->op->start(m, &m->index);
 	}
+	// EOF or an error
 	m->op->stop(m, p);
 	m->count = 0;
 	goto Done;
 Fill:
-	/* they want more? let's try to get some more */
+	// one non-empty record is in the buffer; if they want more,
+	// try to fit more in, but in any case we need to advance
+	// the iterator once for every record shown.
 	while (1) {
 		size_t offs = m->count;
 		loff_t pos = m->index;
@@ -259,30 +262,27 @@ ssize_t seq_read_iter(struct kiocb *iocb, struct iov_iter *iter)
 					    m->op->next);
 			m->index++;
 		}
-		if (!p || IS_ERR(p)) {
-			err = PTR_ERR(p);
+		if (!p || IS_ERR(p))	// no next record for us
 			break;
-		}
-		if (m->count >= size)
+		if (m->count >= iov_iter_count(iter))
 			break;
 		err = m->op->show(m, p);
-		if (seq_has_overflowed(m) || err) {
+		if (err > 0) {		// ->show() says "skip it"
 			m->count = offs;
-			if (likely(err <= 0))
-				break;
+		} else if (err || seq_has_overflowed(m)) {
+			m->count = offs;
+			break;
 		}
 	}
 	m->op->stop(m, p);
-	n = min(m->count, size);
-	if (copy_to_iter(m->buf, n, iter) != n)
-		goto Efault;
+	n = copy_to_iter(m->buf, m->count, iter);
 	copied += n;
 	m->count -= n;
 	m->from = n;
 Done:
-	if (!copied)
-		copied = err;
-	else {
+	if (unlikely(!copied)) {
+		copied = m->count ? -EFAULT : err;
+	} else {
 		iocb->ki_pos += copied;
 		m->read_pos += copied;
 	}
@@ -291,9 +291,6 @@ ssize_t seq_read_iter(struct kiocb *iocb, struct iov_iter *iter)
 Enomem:
 	err = -ENOMEM;
 	goto Done;
-Efault:
-	err = -EFAULT;
-	goto Done;
 }
 EXPORT_SYMBOL(seq_read_iter);