mtd: Update internal API to support 64-bit device size

MTD internal API presently uses 32-bit values to represent device
size. This patch updates them to 64-bits but leaves the external API
unchanged.

In general, changing from 32-bit to 64-bit values cause little
or no changes to the majority of the code with the following
exceptions:
  - printk message formats;
  - division and modulus of 64-bit values (mtd_div_by_wb,
    mtd_div_by_eb may be used in some of such cases).

Was tested on phyFLEX i.MX6.

Signed-off-by: Dmitry Lavnikevich <d.lavnikevich@sam-solutions.com>
Signed-off-by: Grigory Milev <g.milev@sam-solutions.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

2 files changed, 20 insertions, 3 deletions

diff --git a/include/linux/mtd/mtd-abi.h b/include/linux/mtd/mtd-abi.h
index 11d51e2744..c1ba55bd2d 100644
--- a/include/linux/mtd/mtd-abi.h
+++ b/include/linux/mtd/mtd-abi.h
@@ -9,6 +9,8 @@
 
 #ifndef DOXYGEN_SHOULD_SKIP_THIS
 
+#include <asm-generic/div64.h>
+
 struct erase_info_user {
 	uint32_t start;
 	uint32_t length;
@@ -73,7 +75,7 @@ enum {
 struct mtd_info_user {
 	uint8_t type;
 	uint32_t flags;
-	uint32_t size;	 // Total size of the MTD
+	uint64_t size;	 /* Total size of the MTD */
 	uint32_t erasesize;
 	uint32_t writesize;
 	uint32_t oobsize;   // Amount of OOB data per block (e.g. 16)
@@ -173,6 +175,14 @@ enum mtd_file_modes {
 	MTD_MODE_RAW,
 };
 
+
+static inline uint32_t mtd_user_div_by_eb(uint64_t sz,
+	struct mtd_info_user *mtd_user)
+{
+	do_div(sz, mtd_user->erasesize);
+	return sz;
+}
+
 #endif /* DOXYGEN_SHOULD_SKIP_THIS */
 
 #endif /* __MTD_ABI_H__ */
diff --git a/include/linux/mtd/mtd.h b/include/linux/mtd/mtd.h
index e02204a503..970cdb02fa 100644
--- a/include/linux/mtd/mtd.h
+++ b/include/linux/mtd/mtd.h
@@ -86,7 +86,7 @@ struct mtd_oob_ops {
 struct mtd_info {
 	u_char type;
 	u_int32_t flags;
-	u_int32_t size;	 // Total size of the MTD
+	u_int64_t size;	 /* Total size of the MTD */
 
 	/* "Major" erase size for the device. Naïve users may take this
 	 * to be the only erase size available, or may use the more detailed
@@ -219,7 +219,7 @@ struct mtd_info {
 	int p_allow_erasebad;
 
 	struct mtd_info *master;
-	uint32_t master_offset;
+	loff_t master_offset;
 };
 
 int mtd_erase(struct mtd_info *mtd, struct erase_info *instr);
@@ -256,6 +256,13 @@ static inline uint32_t mtd_mod_by_eb(uint64_t sz, struct mtd_info *mtd)
 {
 	return do_div(sz, mtd->erasesize);
 }
+
+static inline uint32_t mtd_div_by_wb(uint64_t sz, struct mtd_info *mtd)
+{
+	do_div(sz, mtd->writesize);
+	return sz;
+}
+
 	/* Kernel-side ioctl definitions */
 
 extern int add_mtd_device(struct mtd_info *mtd, char *devname, int device_id);