scsi: smartpqi: fix critical ARM issue reading PQI index registers

Use the readl() kernel function to read all index registers. For ARM
systems, this function includes a read memory barrier that eliminates ci/pi
corruption.

Reviewed-by: Scott Benesh <scott.benesh@microsemi.com>
Reviewed-by: Scott Teel <scott.teel@microsemi.com>
Tested-by: Shunyong Yang <shunyong.yang@hxt-semitech.com>
Signed-off-by: Kevin Barnett <kevin.barnett@microsemi.com>
Signed-off-by: Don Brace <don.brace@microsemi.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/smartpqi/smartpqi.h b/drivers/scsi/smartpqi/smartpqi.h
index a8e7c4d48061162bd96852cd775131db7d3f09b0..e97bf26703153312a3374a9e450dcd5f63f254fc 100644 (file)
--- a/drivers/scsi/smartpqi/smartpqi.h
+++ b/drivers/scsi/smartpqi/smartpqi.h
@@ -583,8 +583,8 @@ struct pqi_admin_queues_aligned {
 struct pqi_admin_queues {
        void            *iq_element_array;
        void            *oq_element_array;
-       volatile pqi_index_t *iq_ci;
-       volatile pqi_index_t *oq_pi;
+       pqi_index_t     *iq_ci;
+       pqi_index_t __iomem *oq_pi;
        dma_addr_t      iq_element_array_bus_addr;
        dma_addr_t      oq_element_array_bus_addr;
        dma_addr_t      iq_ci_bus_addr;
@@ -608,8 +608,8 @@ struct pqi_queue_group {
        dma_addr_t      oq_element_array_bus_addr;
        __le32 __iomem  *iq_pi[2];
        pqi_index_t     iq_pi_copy[2];
-       volatile pqi_index_t *iq_ci[2];
-       volatile pqi_index_t *oq_pi;
+       pqi_index_t __iomem     *iq_ci[2];
+       pqi_index_t __iomem     *oq_pi;
        dma_addr_t      iq_ci_bus_addr[2];
        dma_addr_t      oq_pi_bus_addr;
        __le32 __iomem  *oq_ci;
@@ -622,7 +622,7 @@ struct pqi_event_queue {
        u16             oq_id;
        u16             int_msg_num;
        void            *oq_element_array;
-       volatile pqi_index_t *oq_pi;
+       pqi_index_t __iomem     *oq_pi;
        dma_addr_t      oq_element_array_bus_addr;
        dma_addr_t      oq_pi_bus_addr;
        __le32 __iomem  *oq_ci;

diff --git a/drivers/scsi/smartpqi/smartpqi_init.c b/drivers/scsi/smartpqi/smartpqi_init.c
index 8b70b879735ef0965b0670678bbd3959960207b6..b4a685ed9ed151059c74f8f1331abe74a9b5a4b2 100644 (file)
--- a/drivers/scsi/smartpqi/smartpqi_init.c
+++ b/drivers/scsi/smartpqi/smartpqi_init.c
@@ -2703,7 +2703,7 @@ static unsigned int pqi_process_io_intr(struct pqi_ctrl_info *ctrl_info,
        oq_ci = queue_group->oq_ci_copy;
 
        while (1) {
-               oq_pi = *queue_group->oq_pi;
+               oq_pi = readl(queue_group->oq_pi);
                if (oq_pi == oq_ci)
                        break;
 
@@ -2794,7 +2794,7 @@ static void pqi_send_event_ack(struct pqi_ctrl_info *ctrl_info,
                spin_lock_irqsave(&queue_group->submit_lock[RAID_PATH], flags);
 
                iq_pi = queue_group->iq_pi_copy[RAID_PATH];
-               iq_ci = *queue_group->iq_ci[RAID_PATH];
+               iq_ci = readl(queue_group->iq_ci[RAID_PATH]);
 
                if (pqi_num_elements_free(iq_pi, iq_ci,
                        ctrl_info->num_elements_per_iq))
@@ -2953,7 +2953,7 @@ static unsigned int pqi_process_event_intr(struct pqi_ctrl_info *ctrl_info)
        oq_ci = event_queue->oq_ci_copy;
 
        while (1) {
-               oq_pi = *event_queue->oq_pi;
+               oq_pi = readl(event_queue->oq_pi);
                if (oq_pi == oq_ci)
                        break;
 
@@ -3177,7 +3177,7 @@ static int pqi_alloc_operational_queues(struct pqi_ctrl_info *ctrl_info)
        size_t element_array_length_per_iq;
        size_t element_array_length_per_oq;
        void *element_array;
-       void *next_queue_index;
+       void __iomem *next_queue_index;
        void *aligned_pointer;
        unsigned int num_inbound_queues;
        unsigned int num_outbound_queues;
@@ -3273,7 +3273,7 @@ static int pqi_alloc_operational_queues(struct pqi_ctrl_info *ctrl_info)
        element_array += PQI_NUM_EVENT_QUEUE_ELEMENTS *
                PQI_EVENT_OQ_ELEMENT_LENGTH;
 
-       next_queue_index = PTR_ALIGN(element_array,
+       next_queue_index = (void __iomem *)PTR_ALIGN(element_array,
                PQI_OPERATIONAL_INDEX_ALIGNMENT);
 
        for (i = 0; i < ctrl_info->num_queue_groups; i++) {
@@ -3281,21 +3281,24 @@ static int pqi_alloc_operational_queues(struct pqi_ctrl_info *ctrl_info)
                queue_group->iq_ci[RAID_PATH] = next_queue_index;
                queue_group->iq_ci_bus_addr[RAID_PATH] =
                        ctrl_info->queue_memory_base_dma_handle +
-                       (next_queue_index - ctrl_info->queue_memory_base);
+                       (next_queue_index -
+                       (void __iomem *)ctrl_info->queue_memory_base);
                next_queue_index += sizeof(pqi_index_t);
                next_queue_index = PTR_ALIGN(next_queue_index,
                        PQI_OPERATIONAL_INDEX_ALIGNMENT);
                queue_group->iq_ci[AIO_PATH] = next_queue_index;
                queue_group->iq_ci_bus_addr[AIO_PATH] =
                        ctrl_info->queue_memory_base_dma_handle +
-                       (next_queue_index - ctrl_info->queue_memory_base);
+                       (next_queue_index -
+                       (void __iomem *)ctrl_info->queue_memory_base);
                next_queue_index += sizeof(pqi_index_t);
                next_queue_index = PTR_ALIGN(next_queue_index,
                        PQI_OPERATIONAL_INDEX_ALIGNMENT);
                queue_group->oq_pi = next_queue_index;
                queue_group->oq_pi_bus_addr =
                        ctrl_info->queue_memory_base_dma_handle +
-                       (next_queue_index - ctrl_info->queue_memory_base);
+                       (next_queue_index -
+                       (void __iomem *)ctrl_info->queue_memory_base);
                next_queue_index += sizeof(pqi_index_t);
                next_queue_index = PTR_ALIGN(next_queue_index,
                        PQI_OPERATIONAL_INDEX_ALIGNMENT);
@@ -3304,7 +3307,8 @@ static int pqi_alloc_operational_queues(struct pqi_ctrl_info *ctrl_info)
        ctrl_info->event_queue.oq_pi = next_queue_index;
        ctrl_info->event_queue.oq_pi_bus_addr =
                ctrl_info->queue_memory_base_dma_handle +
-               (next_queue_index - ctrl_info->queue_memory_base);
+               (next_queue_index -
+               (void __iomem *)ctrl_info->queue_memory_base);
 
        return 0;
 }
@@ -3378,7 +3382,8 @@ static int pqi_alloc_admin_queues(struct pqi_ctrl_info *ctrl_info)
        admin_queues->oq_element_array =
                &admin_queues_aligned->oq_element_array;
        admin_queues->iq_ci = &admin_queues_aligned->iq_ci;
-       admin_queues->oq_pi = &admin_queues_aligned->oq_pi;
+       admin_queues->oq_pi =
+               (pqi_index_t __iomem *)&admin_queues_aligned->oq_pi;
 
        admin_queues->iq_element_array_bus_addr =
                ctrl_info->admin_queue_memory_base_dma_handle +
@@ -3394,8 +3399,8 @@ static int pqi_alloc_admin_queues(struct pqi_ctrl_info *ctrl_info)
                ctrl_info->admin_queue_memory_base);
        admin_queues->oq_pi_bus_addr =
                ctrl_info->admin_queue_memory_base_dma_handle +
-               ((void *)admin_queues->oq_pi -
-               ctrl_info->admin_queue_memory_base);
+               ((void __iomem *)admin_queues->oq_pi -
+               (void __iomem *)ctrl_info->admin_queue_memory_base);
 
        return 0;
 }
@@ -3496,7 +3501,7 @@ static int pqi_poll_for_admin_response(struct pqi_ctrl_info *ctrl_info,
        timeout = (PQI_ADMIN_REQUEST_TIMEOUT_SECS * HZ) + jiffies;
 
        while (1) {
-               oq_pi = *admin_queues->oq_pi;
+               oq_pi = readl(admin_queues->oq_pi);
                if (oq_pi != oq_ci)
                        break;
                if (time_after(jiffies, timeout)) {
@@ -3555,7 +3560,7 @@ static void pqi_start_io(struct pqi_ctrl_info *ctrl_info,
                        DIV_ROUND_UP(iu_length,
                                PQI_OPERATIONAL_IQ_ELEMENT_LENGTH);
 
-               iq_ci = *queue_group->iq_ci[path];
+               iq_ci = readl(queue_group->iq_ci[path]);
 
                if (num_elements_needed > pqi_num_elements_free(iq_pi, iq_ci,
                        ctrl_info->num_elements_per_iq))
@@ -5054,7 +5059,7 @@ static int pqi_wait_until_inbound_queues_empty(struct pqi_ctrl_info *ctrl_info)
                        iq_pi = queue_group->iq_pi_copy[path];
 
                        while (1) {
-                               iq_ci = *queue_group->iq_ci[path];
+                               iq_ci = readl(queue_group->iq_ci[path]);
                                if (iq_ci == iq_pi)
                                        break;
                                pqi_check_ctrl_health(ctrl_info);
@@ -6243,20 +6248,20 @@ static void pqi_reinit_queues(struct pqi_ctrl_info *ctrl_info)
        admin_queues = &ctrl_info->admin_queues;
        admin_queues->iq_pi_copy = 0;
        admin_queues->oq_ci_copy = 0;
-       *admin_queues->oq_pi = 0;
+       writel(0, admin_queues->oq_pi);
 
        for (i = 0; i < ctrl_info->num_queue_groups; i++) {
                ctrl_info->queue_groups[i].iq_pi_copy[RAID_PATH] = 0;
                ctrl_info->queue_groups[i].iq_pi_copy[AIO_PATH] = 0;
                ctrl_info->queue_groups[i].oq_ci_copy = 0;
 
-               *ctrl_info->queue_groups[i].iq_ci[RAID_PATH] = 0;
-               *ctrl_info->queue_groups[i].iq_ci[AIO_PATH] = 0;
-               *ctrl_info->queue_groups[i].oq_pi = 0;
+               writel(0, ctrl_info->queue_groups[i].iq_ci[RAID_PATH]);
+               writel(0, ctrl_info->queue_groups[i].iq_ci[AIO_PATH]);
+               writel(0, ctrl_info->queue_groups[i].oq_pi);
        }
 
        event_queue = &ctrl_info->event_queue;
-       *event_queue->oq_pi = 0;
+       writel(0, event_queue->oq_pi);
        event_queue->oq_ci_copy = 0;
 }