Support 'discard sectors' operation.

[pandora-kernel.git] / drivers / mtd / ftl.c

diff --git a/drivers/mtd/ftl.c b/drivers/mtd/ftl.c
index f34f20c..9bf581c 100644 (file)
--- a/drivers/mtd/ftl.c
+++ b/drivers/mtd/ftl.c
@@ -1005,6 +1005,29 @@ static int ftl_writesect(struct mtd_blktrans_dev *dev,
        return ftl_write((void *)dev, buf, block, 1);
 }
 
+static int ftl_discardsect(struct mtd_blktrans_dev *dev,
+                          unsigned long sector, unsigned nr_sects)
+{
+       partition_t *part = (void *)dev;
+       uint32_t bsize = 1 << part->header.EraseUnitSize;
+
+       DEBUG(1, "FTL erase sector %ld for %d sectors\n",
+             sector, nr_sects);
+
+       while (nr_sects) {
+               uint32_t old_addr = part->VirtualBlockMap[sector];
+               if (old_addr != 0xffffffff) {
+                       part->VirtualBlockMap[sector] = 0xffffffff;
+                       part->EUNInfo[old_addr/bsize].Deleted++;
+                       if (set_bam_entry(part, old_addr, 0))
+                               return -EIO;
+               }
+               nr_sects--;
+               sector++;
+       }
+
+       return 0;
+}
 /*====================================================================*/
 
 static void ftl_freepart(partition_t *part)
@@ -1069,6 +1092,7 @@ static struct mtd_blktrans_ops ftl_tr = {
        .blksize        = SECTOR_SIZE,
        .readsect       = ftl_readsect,
        .writesect      = ftl_writesect,
+       .discard        = ftl_discardsect,
        .getgeo         = ftl_getgeo,
        .add_mtd        = ftl_add_mtd,
        .remove_dev     = ftl_remove_dev,