mtd: add MEMERASE64 ioctl for >4GiB devices

New MEMERASE/MEMREADOOB/MEMWRITEOOB ioctls are needed in order to support
64-bit offsets into large NAND flash devices.

Signed-off-by: Kevin Cernekee <kpc.mtd@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

3 files changed, 28 insertions, 8 deletions

diff --git a/drivers/mtd/mtdchar.c b/drivers/mtd/mtdchar.c
index 763d3f0a1f42..ad4b8618977d 100644
--- a/drivers/mtd/mtdchar.c
+++ b/drivers/mtd/mtdchar.c
@@ -417,6 +417,7 @@ static int mtd_ioctl(struct inode *inode, struct file *file,
                 break;
 
         case MEMERASE:
+        case MEMERASE64:
         {
                 struct erase_info *erase;
 
@@ -427,20 +428,32 @@ static int mtd_ioctl(struct inode *inode, struct file *file,
                 if (!erase)
                         ret = -ENOMEM;
                 else {
-                        struct erase_info_user einfo;
-
                         wait_queue_head_t waitq;
                         DECLARE_WAITQUEUE(wait, current);
 
                         init_waitqueue_head(&waitq);
 
-                        if (copy_from_user(&einfo, argp,
-                                    sizeof(struct erase_info_user))) {
-                                kfree(erase);
-                                return -EFAULT;
+                        if (cmd == MEMERASE64) {
+                                struct erase_info_user64 einfo64;
+
+                                if (copy_from_user(&einfo64, argp,
+                                            sizeof(struct erase_info_user64))) {
+                                        kfree(erase);
+                                        return -EFAULT;
+                                }
+                                erase->addr = einfo64.start;
+                                erase->len = einfo64.length;
+                        } else {
+                                struct erase_info_user einfo32;
+
+                                if (copy_from_user(&einfo32, argp,
+                                            sizeof(struct erase_info_user))) {
+                                        kfree(erase);
+                                        return -EFAULT;
+                                }
+                                erase->addr = einfo32.start;
+                                erase->len = einfo32.length;
                         }
-                        erase->addr = einfo.start;
-                        erase->len = einfo.length;
                         erase->mtd = mtd;
                         erase->callback = mtdchar_erase_callback;
                         erase->priv = (unsigned long)&waitq;
diff --git a/fs/compat_ioctl.c b/fs/compat_ioctl.c
index b83f6bcfa51a..c603ca2c223a 100644
--- a/fs/compat_ioctl.c
+++ b/fs/compat_ioctl.c
@@ -2441,6 +2441,7 @@ COMPATIBLE_IOCTL(MEMGETREGIONCOUNT)
 COMPATIBLE_IOCTL(MEMGETREGIONINFO)
 COMPATIBLE_IOCTL(MEMGETBADBLOCK)
 COMPATIBLE_IOCTL(MEMSETBADBLOCK)
+COMPATIBLE_IOCTL(MEMERASE64)
 /* NBD */
 ULONG_IOCTL(NBD_SET_SOCK)
 ULONG_IOCTL(NBD_SET_BLKSIZE)
diff --git a/include/mtd/mtd-abi.h b/include/mtd/mtd-abi.h
index b6595b3c68b6..2e32be1e3a1e 100644
--- a/include/mtd/mtd-abi.h
+++ b/include/mtd/mtd-abi.h
@@ -12,6 +12,11 @@ struct erase_info_user {
         __u32 length;
 };
 
+struct erase_info_user64 {
+        __u64 start;
+        __u64 length;
+};
+
 struct mtd_oob_buf {
         __u32 start;
         __u32 length;
@@ -95,6 +100,7 @@ struct otp_info {
 #define ECCGETLAYOUT            _IOR('M', 17, struct nand_ecclayout)
 #define ECCGETSTATS             _IOR('M', 18, struct mtd_ecc_stats)
 #define MTDFILEMODE             _IO('M', 19)
+#define MEMERASE64              _IOW('M', 20, struct erase_info_user64)
 
 /*
  * Obsolete legacy interface. Keep it in order not to break userspace