[PATCH] sd: read-only switch

Support for the read-only switch on SD cards which must be enforced by the
host.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 7 insertions, 2 deletions

diff --git a/drivers/mmc/mmc_block.c b/drivers/mmc/mmc_block.c
index d4eee99c2bf6..fa83f15fdf16 100644
--- a/drivers/mmc/mmc_block.c
+++ b/drivers/mmc/mmc_block.c
@@ -95,6 +95,10 @@ static int mmc_blk_open(struct inode *inode, struct file *filp)
                 if (md->usage == 2)
                         check_disk_change(inode->i_bdev);
                 ret = 0;
+
+                if ((filp->f_mode & FMODE_WRITE) &&
+                        mmc_card_readonly(md->queue.card))
+                        ret = -EROFS;
         }
 
         return ret;
@@ -403,9 +407,10 @@ static int mmc_blk_probe(struct mmc_card *card)
         if (err)
                 goto out;
 
-        printk(KERN_INFO "%s: %s %s %dKiB\n",
+        printk(KERN_INFO "%s: %s %s %dKiB %s\n",
                 md->disk->disk_name, mmc_card_id(card), mmc_card_name(card),
-                (card->csd.capacity << card->csd.read_blkbits) / 1024);
+                (card->csd.capacity << card->csd.read_blkbits) / 1024,
+                mmc_card_readonly(card)?"(ro)":"");
 
         mmc_set_drvdata(card, md);
         add_disk(md->disk);