block: remove bvec_kmap_irq and bvec_kunmap_irq

These two helpers are entirely unused now.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20210727055646.118787-10-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

include/linux/bio.h

@@ -5,7 +5,6 @@
 #ifndef __LINUX_BIO_H
 #define __LINUX_BIO_H
 
-#include <linux/highmem.h>
 #include <linux/mempool.h>
 #include <linux/ioprio.h>
 /* struct bio, bio_vec and BIO_* flags are defined in blk_types.h */
@@ -519,47 +518,6 @@ static inline void bio_clone_blkg_association(struct bio *dst,
 					      struct bio *src) { }
 #endif	/* CONFIG_BLK_CGROUP */
 
-#ifdef CONFIG_HIGHMEM
-/*
- * remember never ever reenable interrupts between a bvec_kmap_irq and
- * bvec_kunmap_irq!
- */
-static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
-{
-	unsigned long addr;
-
-	/*
-	 * might not be a highmem page, but the preempt/irq count
-	 * balancing is a lot nicer this way
-	 */
-	local_irq_save(*flags);
-	addr = (unsigned long) kmap_atomic(bvec->bv_page);
-
-	BUG_ON(addr & ~PAGE_MASK);
-
-	return (char *) addr + bvec->bv_offset;
-}
-
-static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
-{
-	unsigned long ptr = (unsigned long) buffer & PAGE_MASK;
-
-	kunmap_atomic((void *) ptr);
-	local_irq_restore(*flags);
-}
-
-#else
-static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
-{
-	return page_address(bvec->bv_page) + bvec->bv_offset;
-}
-
-static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
-{
-	*flags = 0;
-}
-#endif
-
 /*
  * BIO list management for use by remapping drivers (e.g. DM or MD) and loop.
  *