NVMe: Add support for timing out I/Os

In the kthread, walk the list of outstanding I/Os and check they've not
hit the timeout.

Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>

1 files changed, 31 insertions, 6 deletions

diff --git a/drivers/block/nvme.c b/drivers/block/nvme.c
index 9ca9db903ceb..9c0ab2af0fae 100644
--- a/drivers/block/nvme.c
+++ b/drivers/block/nvme.c
@@ -18,6 +18,7 @@
 
 #include <linux/nvme.h>
 #include <linux/bio.h>
+#include <linux/bitops.h>
 #include <linux/blkdev.h>
 #include <linux/errno.h>
 #include <linux/fs.h>
@@ -601,15 +602,15 @@ static void sync_completion(struct nvme_queue *nvmeq, void *ctx,
 typedef void (*completion_fn)(struct nvme_queue *, void *,
                                                 struct nvme_completion *);
 
+static const completion_fn nvme_completions[4] = {
+        [sync_completion_id] = sync_completion,
+        [bio_completion_id]  = bio_completion,
+};
+
 static irqreturn_t nvme_process_cq(struct nvme_queue *nvmeq)
 {
         u16 head, phase;
 
-        static const completion_fn completions[4] = {
-                [sync_completion_id] = sync_completion,
-                [bio_completion_id]  = bio_completion,
-        };
-
         head = nvmeq->cq_head;
         phase = nvmeq->cq_phase;
 
@@ -629,7 +630,7 @@ static irqreturn_t nvme_process_cq(struct nvme_queue *nvmeq)
                 data = free_cmdid(nvmeq, cqe.command_id);
                 handler = data & 3;
                 ptr = (void *)(data & ~3UL);
-                completions[handler](nvmeq, ptr, &cqe);
+                nvme_completions[handler](nvmeq, ptr, &cqe);
         }
 
         /* If the controller ignores the cq head doorbell and continuously
@@ -1172,6 +1173,29 @@ static const struct block_device_operations nvme_fops = {
         .compat_ioctl   = nvme_ioctl,
 };
 
+static void nvme_timeout_ios(struct nvme_queue *nvmeq)
+{
+        int depth = nvmeq->q_depth - 1;
+        struct nvme_cmd_info *info = nvme_cmd_info(nvmeq);
+        unsigned long now = jiffies;
+        int cmdid;
+
+        for_each_set_bit(cmdid, nvmeq->cmdid_data, depth) {
+                unsigned long data;
+                void *ptr;
+                unsigned char handler;
+                static struct nvme_completion cqe = { .status = cpu_to_le16(NVME_SC_ABORT_REQ) << 1, };
+
+                if (!time_after(now, info[cmdid].timeout))
+                        continue;
+                dev_warn(nvmeq->q_dmadev, "Timing out I/O %d\n", cmdid);
+                data = cancel_cmdid(nvmeq, cmdid);
+                handler = data & 3;
+                ptr = (void *)(data & ~3UL);
+                nvme_completions[handler](nvmeq, ptr, &cqe);
+        }
+}
+
 static void nvme_resubmit_bios(struct nvme_queue *nvmeq)
 {
         while (bio_list_peek(&nvmeq->sq_cong)) {
@@ -1203,6 +1227,7 @@ static int nvme_kthread(void *data)
                                 spin_lock_irq(&nvmeq->q_lock);
                                 if (nvme_process_cq(nvmeq))
                                         printk("process_cq did something\n");
+                                nvme_timeout_ios(nvmeq);
                                 nvme_resubmit_bios(nvmeq);
                                 spin_unlock_irq(&nvmeq->q_lock);
                         }