lightnvm: introduce nvm_submit_ppa

Internal logic for both core and media managers, does not have a
backing bio for issuing I/Os. Introduce nvm_submit_ppa to allow raw
I/Os to be submitted to the underlying device driver.

The function request the device, ppa, data buffer and its length and
will submit the I/O synchronously to the device. The return value may
therefore be used to detect any errors regarding the issued I/O.

Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>

1 files changed, 44 insertions, 1 deletions

diff --git a/drivers/lightnvm/core.c b/drivers/lightnvm/core.c
index dad84ddbefb4..dc83e010d084 100644
--- a/drivers/lightnvm/core.c
+++ b/drivers/lightnvm/core.c
@@ -296,7 +296,7 @@ void nvm_end_io(struct nvm_rq *rqd, int error)
 }
 EXPORT_SYMBOL(nvm_end_io);
 
-static void nvm_end_io_sync(struct nvm_rq *rqd, int errors)
+static void nvm_end_io_sync(struct nvm_rq *rqd)
 {
         struct completion *waiting = rqd->wait;
 
@@ -305,6 +305,49 @@ static void nvm_end_io_sync(struct nvm_rq *rqd, int errors)
         complete(waiting);
 }
 
+int nvm_submit_ppa(struct nvm_dev *dev, struct ppa_addr *ppa, int nr_ppas,
+                                int opcode, int flags, void *buf, int len)
+{
+        DECLARE_COMPLETION_ONSTACK(wait);
+        struct nvm_rq rqd;
+        struct bio *bio;
+        int ret;
+        unsigned long hang_check;
+
+        bio = bio_map_kern(dev->q, buf, len, GFP_KERNEL);
+        if (IS_ERR_OR_NULL(bio))
+                return -ENOMEM;
+
+        memset(&rqd, 0, sizeof(struct nvm_rq));
+        ret = nvm_set_rqd_ppalist(dev, &rqd, ppa, nr_ppas);
+        if (ret) {
+                bio_put(bio);
+                return ret;
+        }
+
+        rqd.opcode = opcode;
+        rqd.bio = bio;
+        rqd.wait = &wait;
+        rqd.dev = dev;
+        rqd.end_io = nvm_end_io_sync;
+        rqd.flags = flags;
+        nvm_generic_to_addr_mode(dev, &rqd);
+
+        ret = dev->ops->submit_io(dev, &rqd);
+
+        /* Prevent hang_check timer from firing at us during very long I/O */
+        hang_check = sysctl_hung_task_timeout_secs;
+        if (hang_check)
+                while (!wait_for_completion_io_timeout(&wait, hang_check * (HZ/2)));
+        else
+                wait_for_completion_io(&wait);
+
+        nvm_free_rqd_ppalist(dev, &rqd);
+
+        return rqd.error;
+}
+EXPORT_SYMBOL(nvm_submit_ppa);
+
 static int nvm_core_init(struct nvm_dev *dev)
 {
         struct nvm_id *id = &dev->identity;