[PATCH] ide: fix imbalance preempt count with taskfile PIO

Noticed by Tejun Huh <tejun@aratech.co.kr>.

diff --git a/include/linux/ide.h b/include/linux/ide.h
index e7c50528e10e2c52fb20f0f3bca7e315fa92d3d6..bda3346af22f71fb4c1efb211bf7cf268dcdc19e 100644 (file)
--- a/include/linux/ide.h
+++ b/include/linux/ide.h
@@ -850,29 +850,6 @@ static inline void ide_unmap_buffer(struct request *rq, char *buffer, unsigned l
        if (rq->bio)
                bio_kunmap_irq(buffer, flags);
 }
-
-#else /* !CONFIG_IDE_TASKFILE_IO */
-
-static inline void *task_map_rq(struct request *rq, unsigned long *flags)
-{
-       /*
-        * fs request
-        */
-       if (rq->cbio)
-               return rq_map_buffer(rq, flags);
-
-       /*
-        * task request
-        */
-       return rq->buffer + blk_rq_offset(rq);
-}
-
-static inline void task_unmap_rq(struct request *rq, char *buffer, unsigned long *flags)
-{
-       if (rq->cbio)
-               rq_unmap_buffer(buffer, flags);
-}
-
 #endif /* !CONFIG_IDE_TASKFILE_IO */
 
 #define IDE_CHIPSET_PCI_MASK   \
@@ -1472,9 +1449,19 @@ static inline void task_sectors(ide_drive_t *drive, struct request *rq,
                                unsigned nsect, int rw)
 {
        unsigned long flags;
+       unsigned int bio_rq;
        char *buf;
 
-       buf = task_map_rq(rq, &flags);
+       /*
+        * bio_rq flag is needed because we can call
+        * rq_unmap_buffer() with rq->cbio == NULL
+        */
+       bio_rq = rq->cbio ? 1 : 0;
+
+       if (bio_rq)
+               buf = rq_map_buffer(rq, &flags);        /* fs request */
+       else
+               buf = rq->buffer + blk_rq_offset(rq);   /* task request */
 
        /*
         * IRQ can happen instantly after reading/writing
@@ -1487,9 +1474,9 @@ static inline void task_sectors(ide_drive_t *drive, struct request *rq,
        else
                taskfile_input_data(drive, buf, nsect * SECTOR_WORDS);
 
-       task_unmap_rq(rq, buf, &flags);
+       if (bio_rq)
+               rq_unmap_buffer(buf, &flags);
 }
-
 #endif /* CONFIG_IDE_TASKFILE_IO */
 
 extern int drive_is_ready(ide_drive_t *);