diff options
| -rw-r--r-- | drivers/mtd/devices/mtdram.c | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/drivers/mtd/devices/mtdram.c b/drivers/mtd/devices/mtdram.c index cbd8547d7aad..4418629e8dc0 100644 --- a/drivers/mtd/devices/mtdram.c +++ b/drivers/mtd/devices/mtdram.c @@ -13,6 +13,7 @@ #include <linux/slab.h> #include <linux/ioport.h> #include <linux/vmalloc.h> +#include <linux/mm.h> #include <linux/init.h> #include <linux/mtd/mtd.h> #include <linux/mtd/mtdram.h> @@ -69,6 +70,27 @@ static int ram_point(struct mtd_info *mtd, loff_t from, size_t len, { *virt = mtd->priv + from; *retlen = len; + + if (phys) { + /* limit retlen to the number of contiguous physical pages */ + unsigned long page_ofs = offset_in_page(*virt); + void *addr = *virt - page_ofs; + unsigned long pfn1, pfn0 = vmalloc_to_pfn(addr); + + *phys = __pfn_to_phys(pfn0) + page_ofs; + len += page_ofs; + while (len > PAGE_SIZE) { + len -= PAGE_SIZE; + addr += PAGE_SIZE; + pfn0++; + pfn1 = vmalloc_to_pfn(addr); + if (pfn1 != pfn0) { + *retlen = addr - *virt; + break; + } + } + } + return 0; } |