mg_disk: clean up request completion paths

mg_disk implements its own partial completion.  Convert to standard
block layer partial completion.

[ Impact: cleanup ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: unsik Kim <donari75@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

1 files changed, 33 insertions, 84 deletions

diff --git a/drivers/block/mg_disk.c b/drivers/block/mg_disk.c
index 2c6127ee8343..1a4cc968cfee 100644
--- a/drivers/block/mg_disk.c
+++ b/drivers/block/mg_disk.c
@@ -503,95 +503,68 @@ static unsigned int mg_out(struct mg_host *host,
 
 static void mg_read(struct request *req)
 {
-        u32 remains, j;
+        u32 j;
         struct mg_host *host = req->rq_disk->private_data;
 
-        remains = req->nr_sectors;
-
         if (mg_out(host, req->sector, req->nr_sectors, MG_CMD_RD, NULL) !=
                         MG_ERR_NONE)
                 mg_bad_rw_intr(host);
 
         MG_DBG("requested %d sects (from %ld), buffer=0x%p\n",
-                        remains, req->sector, req->buffer);
+               req->nr_sectors, req->sector, req->buffer);
+
+        do {
+                u16 *buff = (u16 *)req->buffer;
 
-        while (remains) {
                 if (mg_wait(host, MG_REG_STATUS_BIT_DATA_REQ,
                                         MG_TMAX_WAIT_RD_DRQ) != MG_ERR_NONE) {
                         mg_bad_rw_intr(host);
                         return;
                 }
-                for (j = 0; j < MG_SECTOR_SIZE >> 1; j++) {
-                        *(u16 *)req->buffer =
-                                inw((unsigned long)host->dev_base +
-                                                MG_BUFF_OFFSET + (j << 1));
-                        req->buffer += 2;
-                }
-
-                req->sector++;
-                req->errors = 0;
-                remains = --req->nr_sectors;
-                --req->current_nr_sectors;
-
-                if (req->current_nr_sectors <= 0) {
-                        MG_DBG("remain : %d sects\n", remains);
-                        __blk_end_request_cur(req, 0);
-                        if (remains > 0)
-                                req = elv_next_request(host->breq);
-                }
+                for (j = 0; j < MG_SECTOR_SIZE >> 1; j++)
+                        *buff++ = inw((unsigned long)host->dev_base +
+                                      MG_BUFF_OFFSET + (j << 1));
 
                 outb(MG_CMD_RD_CONF, (unsigned long)host->dev_base +
                                 MG_REG_COMMAND);
-        }
+        } while (__blk_end_request(req, 0, MG_SECTOR_SIZE));
 }
 
 static void mg_write(struct request *req)
 {
-        u32 remains, j;
+        u32 j;
         struct mg_host *host = req->rq_disk->private_data;
 
-        remains = req->nr_sectors;
-
         if (mg_out(host, req->sector, req->nr_sectors, MG_CMD_WR, NULL) !=
                         MG_ERR_NONE) {
                 mg_bad_rw_intr(host);
                 return;
         }
 
-
         MG_DBG("requested %d sects (from %ld), buffer=0x%p\n",
-                        remains, req->sector, req->buffer);
-        while (remains) {
+               req->nr_sectors, req->sector, req->buffer);
+
+        do {
+                u16 *buff = (u16 *)req->buffer;
+
                 if (mg_wait(host, MG_REG_STATUS_BIT_DATA_REQ,
                                         MG_TMAX_WAIT_WR_DRQ) != MG_ERR_NONE) {
                         mg_bad_rw_intr(host);
                         return;
                 }
-                for (j = 0; j < MG_SECTOR_SIZE >> 1; j++) {
-                        outw(*(u16 *)req->buffer,
-                                        (unsigned long)host->dev_base +
-                                        MG_BUFF_OFFSET + (j << 1));
-                        req->buffer += 2;
-                }
-                req->sector++;
-                remains = --req->nr_sectors;
-                --req->current_nr_sectors;
-
-                if (req->current_nr_sectors <= 0) {
-                        MG_DBG("remain : %d sects\n", remains);
-                        __blk_end_request_cur(req, 0);
-                        if (remains > 0)
-                                req = elv_next_request(host->breq);
-                }
+                for (j = 0; j < MG_SECTOR_SIZE >> 1; j++)
+                        outw(*buff++, (unsigned long)host->dev_base +
+                                      MG_BUFF_OFFSET + (j << 1));
 
                 outb(MG_CMD_WR_CONF, (unsigned long)host->dev_base +
                                 MG_REG_COMMAND);
-        }
+        } while (__blk_end_request(req, 0, MG_SECTOR_SIZE));
 }
 
 static void mg_read_intr(struct mg_host *host)
 {
         u32 i;
+        u16 *buff;
         struct request *req;
 
         /* check status */
@@ -612,39 +585,24 @@ static void mg_read_intr(struct mg_host *host)
 ok_to_read:
         /* get current segment of request */
         req = elv_next_request(host->breq);
+        buff = (u16 *)req->buffer;
 
         /* read 1 sector */
-        for (i = 0; i < MG_SECTOR_SIZE >> 1; i++) {
-                *(u16 *)req->buffer =
-                        inw((unsigned long)host->dev_base + MG_BUFF_OFFSET +
-                                        (i << 1));
-                req->buffer += 2;
-        }
+        for (i = 0; i < MG_SECTOR_SIZE >> 1; i++)
+                *buff++ = inw((unsigned long)host->dev_base + MG_BUFF_OFFSET +
+                              (i << 1));
 
-        /* manipulate request */
         MG_DBG("sector %ld, remaining=%ld, buffer=0x%p\n",
                         req->sector, req->nr_sectors - 1, req->buffer);
 
-        req->sector++;
-        req->errors = 0;
-        i = --req->nr_sectors;
-        --req->current_nr_sectors;
-
-        /* let know if current segment done */
-        if (req->current_nr_sectors <= 0)
-                __blk_end_request_cur(req, 0);
-
-        /* set handler if read remains */
-        if (i > 0) {
-                host->mg_do_intr = mg_read_intr;
-                mod_timer(&host->timer, jiffies + 3 * HZ);
-        }
-
         /* send read confirm */
         outb(MG_CMD_RD_CONF, (unsigned long)host->dev_base + MG_REG_COMMAND);
 
-        /* goto next request */
-        if (!i)
+        if (__blk_end_request(req, 0, MG_SECTOR_SIZE)) {
+                /* set handler if read remains */
+                host->mg_do_intr = mg_read_intr;
+                mod_timer(&host->timer, jiffies + 3 * HZ);
+        } else /* goto next request */
                 mg_request(host->breq);
 }
 
@@ -653,6 +611,7 @@ static void mg_write_intr(struct mg_host *host)
         u32 i, j;
         u16 *buff;
         struct request *req;
+        bool rem;
 
         /* get current segment of request */
         req = elv_next_request(host->breq);
@@ -673,18 +632,8 @@ static void mg_write_intr(struct mg_host *host)
         return;
 
 ok_to_write:
-        /* manipulate request */
-        req->sector++;
-        i = --req->nr_sectors;
-        --req->current_nr_sectors;
-        req->buffer += MG_SECTOR_SIZE;
-
-        /* let know if current segment or all done */
-        if (!i || (req->bio && req->current_nr_sectors <= 0))
-                __blk_end_request_cur(req, 0);
-
-        /* write 1 sector and set handler if remains */
-        if (i > 0) {
+        if ((rem = __blk_end_request(req, 0, MG_SECTOR_SIZE))) {
+                /* write 1 sector and set handler if remains */
                 buff = (u16 *)req->buffer;
                 for (j = 0; j < MG_STORAGE_BUFFER_SIZE >> 1; j++) {
                         outw(*buff, (unsigned long)host->dev_base +
@@ -700,7 +649,7 @@ ok_to_write:
         /* send write confirm */
         outb(MG_CMD_WR_CONF, (unsigned long)host->dev_base + MG_REG_COMMAND);
 
-        if (!i)
+        if (!rem)
                 mg_request(host->breq);
 }