[PATCH] UBI: implement atomic LEB change ioctl
Artem Bityutskiy
dedekind at infradead.org
Thu Jan 24 11:54:58 EST 2008
>From 7e8210bd9165ba279ddacd0e4fb28891318b9b66 Mon Sep 17 00:00:00 2001
From: Artem Bityutskiy <Artem.Bityutskiy at nokia.com>
Date: Thu, 24 Jan 2008 18:48:21 +0200
Subject: [PATCH] UBI: implement atomic LEB change ioctl
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy at nokia.com>
---
drivers/mtd/ubi/cdev.c | 72 +++++++++++++++++++++++++++++------
drivers/mtd/ubi/ubi.h | 27 +++++++++++--
drivers/mtd/ubi/upd.c | 99 ++++++++++++++++++++++++++++++++++++++++++++++--
3 files changed, 178 insertions(+), 20 deletions(-)
diff --git a/drivers/mtd/ubi/cdev.c b/drivers/mtd/ubi/cdev.c
index 0c4044d..9d6aae5 100644
--- a/drivers/mtd/ubi/cdev.c
+++ b/drivers/mtd/ubi/cdev.c
@@ -132,8 +132,15 @@ static int vol_cdev_release(struct inode *inode, struct file *file)
if (vol->updating) {
ubi_warn("update of volume %d not finished, volume is damaged",
vol->vol_id);
+ ubi_assert(!vol->changing_leb);
vol->updating = 0;
vfree(vol->upd_buf);
+ } else if (vol->changing_leb) {
+ dbg_msg("only %lld of %lld bytes received for atomic LEB change"
+ " for volume %d:%d, cancel", vol->upd_received,
+ vol->upd_bytes, vol->ubi->ubi_num, vol->vol_id);
+ vol->changing_leb = 0;
+ vfree(vol->upd_buf);
}
ubi_close_volume(desc);
@@ -351,24 +358,32 @@ static ssize_t vol_cdev_write(struct file *file, const char __user *buf,
struct ubi_volume *vol = desc->vol;
struct ubi_device *ubi = vol->ubi;
- if (!vol->updating)
+ if (!vol->updating && !vol->changing_leb)
return vol_cdev_direct_write(file, buf, count, offp);
- err = ubi_more_update_data(ubi, vol, buf, count);
+ if (vol->updating)
+ err = ubi_more_update_data(ubi, vol, buf, count);
+ else
+ err = ubi_more_leb_change_data(ubi, vol, buf, count);
+
if (err < 0) {
- ubi_err("cannot write %zd bytes of update data, error %d",
+ ubi_err("cannot accept more %zd bytes of data, error %d",
count, err);
return err;
}
if (err) {
/*
- * Update is finished, @err contains number of actually written
- * bytes now.
+ * The operation is finished, @err contains number of actually
+ * written bytes.
*/
count = err;
- vol->updating = 0;
+ if (vol->changing_leb) {
+ revoke_exclusive(desc, UBI_READWRITE);
+ return count;
+ }
+
err = ubi_check_volume(ubi, vol->vol_id);
if (err < 0)
return err;
@@ -433,6 +448,43 @@ static int vol_cdev_ioctl(struct inode *inode, struct file *file,
break;
}
+ /* Atomic logical eraseblock change command */
+ case UBI_IOCEBCH:
+ {
+ struct ubi_leb_change_req req;
+
+ err = copy_from_user(&req, argp,
+ sizeof(struct ubi_leb_change_req));
+ if (err) {
+ err = -EFAULT;
+ break;
+ }
+
+ if (desc->mode == UBI_READONLY ||
+ vol->vol_type == UBI_STATIC_VOLUME) {
+ err = -EROFS;
+ break;
+ }
+
+ /* Validate the request */
+ err = -EINVAL;
+ if (req.lnum < 0 || req.lnum >= vol->reserved_pebs ||
+ req.bytes < 0 || req.lnum >= vol->usable_leb_size)
+ break;
+ if (req.dtype != UBI_LONGTERM && req.dtype != UBI_SHORTTERM &&
+ req.dtype != UBI_UNKNOWN)
+ break;
+
+ err = get_exclusive(desc);
+ if (err < 0)
+ break;
+
+ err = ubi_start_leb_change(ubi, vol, &req);
+ if (req.bytes == 0)
+ revoke_exclusive(desc, UBI_READWRITE);
+ break;
+ }
+
#ifdef CONFIG_MTD_UBI_DEBUG_USERSPACE_IO
/* Logical eraseblock erasure command */
case UBI_IOCEBER:
@@ -445,7 +497,8 @@ static int vol_cdev_ioctl(struct inode *inode, struct file *file,
break;
}
- if (desc->mode == UBI_READONLY) {
+ if (desc->mode == UBI_READONLY ||
+ vol->vol_type == UBI_STATIC_VOLUME) {
err = -EROFS;
break;
}
@@ -455,11 +508,6 @@ static int vol_cdev_ioctl(struct inode *inode, struct file *file,
break;
}
- if (vol->vol_type != UBI_DYNAMIC_VOLUME) {
- err = -EROFS;
- break;
- }
-
dbg_msg("erase LEB %d:%d", vol->vol_id, lnum);
err = ubi_eba_unmap_leb(ubi, vol, lnum);
if (err)
diff --git a/drivers/mtd/ubi/ubi.h b/drivers/mtd/ubi/ubi.h
index 3a88cf1..4577106 100644
--- a/drivers/mtd/ubi/ubi.h
+++ b/drivers/mtd/ubi/ubi.h
@@ -158,15 +158,23 @@ struct ubi_volume_desc;
* @name: volume name
*
* @upd_ebs: how many eraseblocks are expected to be updated
- * @upd_bytes: how many bytes are expected to be received
- * @upd_received: how many update bytes were already received
- * @upd_buf: update buffer which is used to collect update data
+ * @ch_lnum: LEB number which is being changing by the atomic LEB change
+ * operation
+ * @ch_dtype: data persistency type which is being changing by the atomic LEB
+ * change operation
+ * @upd_bytes: how many bytes are expected to be received for volume update or
+ * atomic LEB change
+ * @upd_received: how many bytes were already received for volume update or
+ * atomic LEB change
+ * @upd_buf: update buffer which is used to collect update data or data for
+ * atomic LEB change
*
* @eba_tbl: EBA table of this volume (LEB->PEB mapping)
* @checked: %1 if this static volume was checked
* @corrupted: %1 if the volume is corrupted (static volumes only)
* @upd_marker: %1 if the update marker is set for this volume
* @updating: %1 if the volume is being updated
+ * @changing_leb: %1 if the atomic LEB change ioctl command is in progress
*
* @gluebi_desc: gluebi UBI volume descriptor
* @gluebi_refcount: reference count of the gluebi MTD device
@@ -202,6 +210,8 @@ struct ubi_volume {
char name[UBI_VOL_NAME_MAX+1];
int upd_ebs;
+ int ch_lnum;
+ int ch_dtype;
long long upd_bytes;
long long upd_received;
void *upd_buf;
@@ -211,9 +221,14 @@ struct ubi_volume {
int corrupted:1;
int upd_marker:1;
int updating:1;
+ int changing_leb:1;
#ifdef CONFIG_MTD_UBI_GLUEBI
- /* Gluebi-related stuff may be compiled out */
+ /*
+ * Gluebi-related stuff may be compiled out.
+ * TODO: this should not be built into UBI but should be a separate
+ * ubimtd driver which works on top of UBI and emulates MTD devices.
+ */
struct ubi_volume_desc *gluebi_desc;
int gluebi_refcount;
struct mtd_info gluebi_mtd;
@@ -427,6 +442,10 @@ int ubi_start_update(struct ubi_device *ubi, struct ubi_volume *vol,
long long bytes);
int ubi_more_update_data(struct ubi_device *ubi, struct ubi_volume *vol,
const void __user *buf, int count);
+int ubi_start_leb_change(struct ubi_device *ubi, struct ubi_volume *vol,
+ const struct ubi_leb_change_req *req);
+int ubi_more_leb_change_data(struct ubi_device *ubi, struct ubi_volume *vol,
+ const void __user *buf, int count);
/* misc.c */
int ubi_calc_data_len(const struct ubi_device *ubi, const void *buf, int length);
diff --git a/drivers/mtd/ubi/upd.c b/drivers/mtd/ubi/upd.c
index 59c61ab..40f5c0e 100644
--- a/drivers/mtd/ubi/upd.c
+++ b/drivers/mtd/ubi/upd.c
@@ -22,7 +22,8 @@
*/
/*
- * This file contains implementation of the volume update functionality.
+ * This file contains implementation of the volume update and atomic LEB change
+ * functionality.
*
* The update operation is based on the per-volume update marker which is
* stored in the volume table. The update marker is set before the update
@@ -133,6 +134,7 @@ int ubi_start_update(struct ubi_device *ubi, struct ubi_volume *vol,
uint64_t tmp;
dbg_msg("start update of volume %d, %llu bytes", vol->vol_id, bytes);
+ ubi_assert(!vol->updating && !vol->changing_leb);
vol->updating = 1;
err = set_update_marker(ubi, vol);
@@ -168,6 +170,37 @@ int ubi_start_update(struct ubi_device *ubi, struct ubi_volume *vol,
}
/**
+ * ubi_start_leb_change - start atomic LEB change.
+ * @ubi: UBI device description object
+ * @vol: volume description object
+ * @req: operation request
+ *
+ * This function starts atomic LEB change operation. Returns zero in case of
+ * success and a negative error code in case of failure.
+ */
+int ubi_start_leb_change(struct ubi_device *ubi, struct ubi_volume *vol,
+ const struct ubi_leb_change_req *req)
+{
+ ubi_assert(!vol->updating && !vol->changing_leb);
+
+ if (req->bytes == 0)
+ return ubi_eba_atomic_leb_change(ubi, vol, req->lnum, NULL, 0,
+ req->dtype);
+
+ vol->upd_bytes = req->bytes;
+ vol->upd_received = 0;
+ vol->changing_leb = 1;
+ vol->ch_lnum = req->lnum;
+ vol->ch_dtype = req->dtype;
+
+ vol->upd_buf = vmalloc(req->bytes);
+ if (!vol->upd_buf)
+ return -ENOMEM;
+
+ return 0;
+}
+
+/**
* write_leb - write update data.
* @ubi: UBI device description object
* @vol: volume description object
@@ -239,9 +272,9 @@ static int write_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum,
* @count: how much bytes to write
*
* This function writes more data to the volume which is being updated. It may
- * be called arbitrary number of times until all of the update data arrive.
- * This function returns %0 in case of success, number of bytes written during
- * the last call if the whole volume update was successfully finished, and a
+ * be called arbitrary number of times until all the update data arriveis. This
+ * function returns %0 in case of success, number of bytes written during the
+ * last call if the whole volume update has been successfully finished, and a
* negative error code in case of failure.
*/
int ubi_more_update_data(struct ubi_device *ubi, struct ubi_volume *vol,
@@ -340,6 +373,7 @@ int ubi_more_update_data(struct ubi_device *ubi, struct ubi_volume *vol,
return err;
err = ubi_wl_flush(ubi);
if (err == 0) {
+ vol->updating = 0;
err = to_write;
vfree(vol->upd_buf);
}
@@ -347,3 +381,60 @@ int ubi_more_update_data(struct ubi_device *ubi, struct ubi_volume *vol,
return err;
}
+
+/**
+ * ubi_more_leb_change_data - accept more data for atomic LEB change.
+ * @vol: volume description object
+ * @buf: write data (user-space memory buffer)
+ * @count: how much bytes to write
+ *
+ * This function accepts more data to the volume which is being under the
+ * "atomic LEB change" operation. It may be called arbitrary number of times
+ * until all data arrives. This function returns %0 in case of success, number
+ * of bytes written during the last call if the whole "atomic LEB change"
+ * operation has been successfully finished, and a negative error code in case
+ * of failure.
+ */
+int ubi_more_leb_change_data(struct ubi_device *ubi, struct ubi_volume *vol,
+ const void __user *buf, int count)
+{
+ int err;
+
+ dbg_msg("write %d of %lld bytes, %lld already passed",
+ count, vol->upd_bytes, vol->upd_received);
+
+ if (ubi->ro_mode)
+ return -EROFS;
+
+ if (vol->upd_received + count > vol->upd_bytes)
+ count = vol->upd_bytes - vol->upd_received;
+
+ err = copy_from_user(vol->upd_buf + vol->upd_received, buf, count);
+ if (err)
+ return -EFAULT;
+
+ if (vol->upd_received + count == vol->upd_bytes) {
+ int l;
+
+ l = ubi_calc_data_len(ubi, buf, vol->upd_bytes);
+ if (l != vol->upd_bytes)
+ dbg_msg("skip last %lld bytes (0xFF)",
+ vol->upd_bytes - l);
+ err = ubi_eba_atomic_leb_change(ubi, vol, vol->ch_lnum,
+ vol->upd_buf, l, UBI_UNKNOWN);
+ if (err)
+ return err;
+ }
+
+ vol->upd_received += count;
+ buf += count;
+
+ ubi_assert(vol->upd_received <= vol->upd_bytes);
+ if (vol->upd_received == vol->upd_bytes) {
+ vol->changing_leb = 0;
+ err = count;
+ vfree(vol->upd_buf);
+ }
+
+ return err;
+}
--
1.5.3.4
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