[PATCH] drivers/mtd/rfd_ftl.c: implement discard

From: Sean Young
Date: Mon Nov 10 2008 - 10:58:21 EST


Now that discard is supported implement it in RFD FTL. Also stop writing to
flash once an error has been detected and various other cleanups.

Signed-off-by: Sean Young <sean@xxxxxxxx>
--
diff --git a/drivers/mtd/rfd_ftl.c b/drivers/mtd/rfd_ftl.c
index e538c0a..0d028b5 100644
--- a/drivers/mtd/rfd_ftl.c
+++ b/drivers/mtd/rfd_ftl.c
@@ -1,7 +1,7 @@
/*
* rfd_ftl.c -- resident flash disk (flash translation layer)
*
- * Copyright (C) 2005 Sean Young <sean@xxxxxxxx>
+ * Copyright (C) 2005, 2008 Sean Young <sean@xxxxxxxx>
*
* This type of flash translation layer (FTL) is used by the Embedded BIOS
* by General Software. It is known as the Resident Flash Disk (RFD), see:
@@ -241,7 +241,7 @@ err:

static int rfd_ftl_readsect(struct mtd_blktrans_dev *dev, u_long sector, char *buf)
{
- struct partition *part = (struct partition*)dev;
+ struct partition *part = container_of(dev, struct partition, mbd);
u_long addr;
size_t retlen;
int rc;
@@ -293,6 +293,7 @@ static void erase_callback(struct erase_info *erase)
part->blocks[i].used_sectors = 0;

kfree(erase);
+ part->errors++;

return;
}
@@ -317,6 +318,7 @@ static void erase_callback(struct erase_info *erase)
part->mbd.mtd->name,
part->blocks[i].offset);
part->blocks[i].state = BLOCK_FAILED;
+ part->errors++;
}
else
part->blocks[i].state = BLOCK_OK;
@@ -349,6 +351,7 @@ static int erase_block(struct partition *part, int block)
"failed\n", erase->addr, erase->len,
part->mbd.mtd->name);
kfree(erase);
+ part->errors++;
}

err:
@@ -383,7 +386,7 @@ static int move_block_contents(struct partition *part, int block_no, u_long *old
printk(KERN_ERR PREFIX "error reading '%s' at "
"0x%lx\n", part->mbd.mtd->name,
part->blocks[block_no].offset);
-
+ part->errors++;
goto err;
}

@@ -423,7 +426,7 @@ static int move_block_contents(struct partition *part, int block_no, u_long *old
printk(KERN_ERR PREFIX "'%s': Unable to "
"read sector for relocation\n",
part->mbd.mtd->name);
-
+ part->errors++;
goto err;
}

@@ -604,9 +607,10 @@ static int mark_sector_deleted(struct partition *part, u_long old_addr)
if (rc) {
printk(KERN_ERR PREFIX "error writing '%s' at "
"0x%lx\n", part->mbd.mtd->name, addr);
- if (rc)
- goto err;
+ part->errors++;
+ goto err;
}
+
if (block == part->current_block)
part->header_cache[offset + HEADER_MAP_OFFSET] = del;

@@ -639,9 +643,10 @@ static int find_free_sector(const struct partition *part, const struct block *bl
return -1;
}

-static int do_writesect(struct mtd_blktrans_dev *dev, u_long sector, char *buf, ulong *old_addr)
+static int do_writesect(struct mtd_blktrans_dev *dev, u_long sector, char *buf,
+ u_long *old_addr)
{
- struct partition *part = (struct partition*)dev;
+ struct partition *part = container_of(dev, struct partition, mbd);
struct block *block;
u_long addr;
int i;
@@ -677,8 +682,8 @@ static int do_writesect(struct mtd_blktrans_dev *dev, u_long sector, char *buf,
if (rc) {
printk(KERN_ERR PREFIX "error writing '%s' at 0x%lx\n",
part->mbd.mtd->name, addr);
- if (rc)
- goto err;
+ part->errors++;
+ goto err;
}

part->sector_map[sector] = addr;
@@ -697,8 +702,8 @@ static int do_writesect(struct mtd_blktrans_dev *dev, u_long sector, char *buf,
if (rc) {
printk(KERN_ERR PREFIX "error writing '%s' at 0x%lx\n",
part->mbd.mtd->name, addr);
- if (rc)
- goto err;
+ part->errors++;
+ goto err;
}
block->used_sectors++;
block->free_sectors--;
@@ -709,14 +714,14 @@ err:

static int rfd_ftl_writesect(struct mtd_blktrans_dev *dev, u_long sector, char *buf)
{
- struct partition *part = (struct partition*)dev;
+ struct partition *part = container_of(dev, struct partition, mbd);
u_long old_addr;
int i;
int rc = 0;

pr_debug("rfd_ftl_writesect(sector=0x%lx)\n", sector);

- if (part->reserved_block == -1) {
+ if (part->reserved_block == -1 || part->errors) {
rc = -EACCES;
goto err;
}
@@ -750,7 +755,7 @@ err:

static int rfd_ftl_getgeo(struct mtd_blktrans_dev *dev, struct hd_geometry *geo)
{
- struct partition *part = (struct partition*)dev;
+ struct partition *part = container_of(dev, struct partition, mbd);

geo->heads = 1;
geo->sectors = SECTORS_PER_TRACK;
@@ -759,6 +764,30 @@ static int rfd_ftl_getgeo(struct mtd_blktrans_dev *dev, struct hd_geometry *geo)
return 0;
}

+static int rfd_ftl_discardsect(struct mtd_blktrans_dev *dev, u_long sector,
+ uint nr_sects)
+{
+ struct partition *part = container_of(dev, struct partition, mbd);
+ u_long addr;
+ int rc;
+
+ if (part->errors)
+ return -EACCES;
+
+ for (rc = 0; nr_sects && rc == 0; sector++, nr_sects--) {
+ if (sector >= part->sector_count)
+ return -EIO;
+
+ addr = part->sector_map[sector];
+ part->sector_map[sector] = -1;
+
+ if (addr != -1)
+ rc = mark_sector_deleted(part, addr);
+ }
+
+ return rc;
+}
+
static void rfd_ftl_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd)
{
struct partition *part;
@@ -806,7 +835,7 @@ out:

static void rfd_ftl_remove_dev(struct mtd_blktrans_dev *dev)
{
- struct partition *part = (struct partition*)dev;
+ struct partition *part = container_of(dev, struct partition, mbd);
int i;

for (i=0; i<part->total_blocks; i++) {
@@ -829,6 +858,7 @@ static struct mtd_blktrans_ops rfd_ftl_tr = {

.readsect = rfd_ftl_readsect,
.writesect = rfd_ftl_writesect,
+ .discard = rfd_ftl_discardsect,
.getgeo = rfd_ftl_getgeo,
.add_mtd = rfd_ftl_add_mtd,
.remove_dev = rfd_ftl_remove_dev,
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/