aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/mtd/mtdchar.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/mtd/mtdchar.c')
-rw-r--r--drivers/mtd/mtdchar.c48
1 files changed, 45 insertions, 3 deletions
diff --git a/drivers/mtd/mtdchar.c b/drivers/mtd/mtdchar.c
index a825002123c..24d35ba62b8 100644
--- a/drivers/mtd/mtdchar.c
+++ b/drivers/mtd/mtdchar.c
@@ -477,6 +477,39 @@ static int mtd_do_readoob(struct mtd_info *mtd, uint64_t start,
return ret;
}
+/*
+ * Copies (and truncates, if necessary) data from the larger struct,
+ * nand_ecclayout, to the smaller, deprecated layout struct,
+ * nand_ecclayout_user. This is necessary only to suppport the deprecated
+ * API ioctl ECCGETLAYOUT while allowing all new functionality to use
+ * nand_ecclayout flexibly (i.e. the struct may change size in new
+ * releases without requiring major rewrites).
+ */
+static int shrink_ecclayout(const struct nand_ecclayout *from,
+ struct nand_ecclayout_user *to)
+{
+ int i;
+
+ if (!from || !to)
+ return -EINVAL;
+
+ memset(to, 0, sizeof(*to));
+
+ to->eccbytes = min((int)from->eccbytes, MTD_MAX_ECCPOS_ENTRIES_OLD);
+ for (i = 0; i < to->eccbytes; i++)
+ to->eccpos[i] = from->eccpos[i];
+
+ for (i = 0; i < MTD_MAX_OOBFREE_ENTRIES; i++) {
+ if (from->oobfree[i].length == 0 &&
+ from->oobfree[i].offset == 0)
+ break;
+ to->oobavail += from->oobfree[i].length;
+ to->oobfree[i] = from->oobfree[i];
+ }
+
+ return 0;
+}
+
static int mtd_ioctl(struct file *file, u_int cmd, u_long arg)
{
struct mtd_file_info *mfi = file->private_data;
@@ -812,14 +845,23 @@ static int mtd_ioctl(struct file *file, u_int cmd, u_long arg)
}
#endif
+ /* This ioctl is being deprecated - it truncates the ecc layout */
case ECCGETLAYOUT:
{
+ struct nand_ecclayout_user *usrlay;
+
if (!mtd->ecclayout)
return -EOPNOTSUPP;
- if (copy_to_user(argp, mtd->ecclayout,
- sizeof(struct nand_ecclayout)))
- return -EFAULT;
+ usrlay = kmalloc(sizeof(*usrlay), GFP_KERNEL);
+ if (!usrlay)
+ return -ENOMEM;
+
+ shrink_ecclayout(mtd->ecclayout, usrlay);
+
+ if (copy_to_user(argp, usrlay, sizeof(*usrlay)))
+ ret = -EFAULT;
+ kfree(usrlay);
break;
}