From: Christoph Hellwig <hch@lst.de>
Date: Tue, 27 Jul 2021 07:56:34 +0200
Subject: [PATCH] bvec: add a bvec_kmap_local helper
Git-commit: e6e7471706dc42cbe0e01278540c0730138d43e5
Patch-mainline: v5.15-rc1
References: jsc#PED1183
Add a helper to call kmap_local_page on a bvec. There is no need for
an unmap helper given that kunmap_local accept any address in the mapped
page.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Link: https://lore.kernel.org/r/20210727055646.118787-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Acked-by: Hannes Reinecke <hare@suse.com>
---
include/linux/bvec.h | 13 +++++++++++++
1 file changed, 13 insertions(+)
diff --git a/include/linux/bvec.h b/include/linux/bvec.h
index 883faf5f1523..f8710af18eef 100644
--- a/include/linux/bvec.h
+++ b/include/linux/bvec.h
@@ -7,6 +7,7 @@
#ifndef __LINUX_BVEC_H
#define __LINUX_BVEC_H
+#include <linux/highmem.h>
#include <linux/bug.h>
#include <linux/errno.h>
#include <linux/limits.h>
@@ -183,4 +184,16 @@ static inline void bvec_advance(const struct bio_vec *bvec,
}
}
+/**
+ * bvec_kmap_local - map a bvec into the kernel virtual address space
+ * @bvec: bvec to map
+ *
+ * Must be called on single-page bvecs only. Call kunmap_local on the returned
+ * address to unmap.
+ */
+static inline void *bvec_kmap_local(struct bio_vec *bvec)
+{
+ return kmap_local_page(bvec->bv_page) + bvec->bv_offset;
+}
+
#endif /* __LINUX_BVEC_H */
--
2.35.3