[1] suggests that fastmap is suitable for large flash devices. Module
parameter 'fm_autoconvert' is a coarse grained switch to enable all
ubi devices to generate fastmap, which may turn on fastmap even for
small flash devices.
This patch imports a new field 'disable_fm' in struct 'ubi_attach_req'
to support following situations by ioctl 'UBI_IOCATT'.
[old functions]
A. Disable 'fm_autoconvert': Disbable fastmap for all ubi devices
B. Enable 'fm_autoconvert': Enable fastmap for all ubi devices
[new function]
C. Enable 'fm_autoconvert', set 'disable_fm' for given device: Don't
create new fastmap and do full scan (existed fastmap will be
destroyed) for the given ubi device.
A simple test case in [2].
[1] http://www.linux-mtd.infradead.org/doc/ubi.html#L_fastmap
[2] https://bugzilla.kernel.org/show_bug.cgi?id=216278
Signed-off-by: Zhihao Cheng <[email protected]>
---
v1->v2:
Make value assignment method more resonable between bool and integer
types.
drivers/mtd/ubi/build.c | 14 ++++++++++----
drivers/mtd/ubi/cdev.c | 2 +-
drivers/mtd/ubi/ubi.h | 3 ++-
include/uapi/mtd/ubi-user.h | 8 +++++++-
4 files changed, 20 insertions(+), 7 deletions(-)
diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c
index a32050fecabf..a901f8edfa41 100644
--- a/drivers/mtd/ubi/build.c
+++ b/drivers/mtd/ubi/build.c
@@ -807,6 +807,7 @@ static int autoresize(struct ubi_device *ubi, int vol_id)
* @ubi_num: number to assign to the new UBI device
* @vid_hdr_offset: VID header offset
* @max_beb_per1024: maximum expected number of bad PEB per 1024 PEBs
+ * @disable_fm: whether disable fastmap
*
* This function attaches MTD device @mtd_dev to UBI and assign @ubi_num number
* to the newly created UBI device, unless @ubi_num is %UBI_DEV_NUM_AUTO, in
@@ -814,11 +815,15 @@ static int autoresize(struct ubi_device *ubi, int vol_id)
* automatically. Returns the new UBI device number in case of success and a
* negative error code in case of failure.
*
+ * If @disable_fm is true, ubi doesn't create new fastmap even the module param
+ * 'fm_autoconvert' is set, and existed old fastmap will be destroyed after
+ * doing full scanning.
+ *
* Note, the invocations of this function has to be serialized by the
* @ubi_devices_mutex.
*/
int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num,
- int vid_hdr_offset, int max_beb_per1024)
+ int vid_hdr_offset, int max_beb_per1024, bool disable_fm)
{
struct ubi_device *ubi;
int i, err;
@@ -921,7 +926,7 @@ int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num,
UBI_FM_MIN_POOL_SIZE);
ubi->fm_wl_pool.max_size = ubi->fm_pool.max_size / 2;
- ubi->fm_disabled = !fm_autoconvert;
+ ubi->fm_disabled = (!fm_autoconvert || disable_fm) ? 1 : 0;
if (fm_debug)
ubi_enable_dbg_chk_fastmap(ubi);
@@ -962,7 +967,7 @@ int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num,
if (!ubi->fm_buf)
goto out_free;
#endif
- err = ubi_attach(ubi, 0);
+ err = ubi_attach(ubi, disable_fm ? 1 : 0);
if (err) {
ubi_err(ubi, "failed to attach mtd%d, error %d",
mtd->index, err);
@@ -1242,7 +1247,8 @@ static int __init ubi_init(void)
mutex_lock(&ubi_devices_mutex);
err = ubi_attach_mtd_dev(mtd, p->ubi_num,
- p->vid_hdr_offs, p->max_beb_per1024);
+ p->vid_hdr_offs, p->max_beb_per1024,
+ false);
mutex_unlock(&ubi_devices_mutex);
if (err < 0) {
pr_err("UBI error: cannot attach mtd%d\n",
diff --git a/drivers/mtd/ubi/cdev.c b/drivers/mtd/ubi/cdev.c
index cc9a28cf9d82..0680ba82255b 100644
--- a/drivers/mtd/ubi/cdev.c
+++ b/drivers/mtd/ubi/cdev.c
@@ -1041,7 +1041,7 @@ static long ctrl_cdev_ioctl(struct file *file, unsigned int cmd,
*/
mutex_lock(&ubi_devices_mutex);
err = ubi_attach_mtd_dev(mtd, req.ubi_num, req.vid_hdr_offset,
- req.max_beb_per1024);
+ req.max_beb_per1024, !!req.disable_fm);
mutex_unlock(&ubi_devices_mutex);
if (err < 0)
put_mtd_device(mtd);
diff --git a/drivers/mtd/ubi/ubi.h b/drivers/mtd/ubi/ubi.h
index 078112e23dfd..947d17e1e434 100644
--- a/drivers/mtd/ubi/ubi.h
+++ b/drivers/mtd/ubi/ubi.h
@@ -937,7 +937,8 @@ int ubi_io_write_vid_hdr(struct ubi_device *ubi, int pnum,
/* build.c */
int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num,
- int vid_hdr_offset, int max_beb_per1024);
+ int vid_hdr_offset, int max_beb_per1024,
+ bool disable_fm);
int ubi_detach_mtd_dev(int ubi_num, int anyway);
struct ubi_device *ubi_get_device(int ubi_num);
void ubi_put_device(struct ubi_device *ubi);
diff --git a/include/uapi/mtd/ubi-user.h b/include/uapi/mtd/ubi-user.h
index b69e9ba6742b..dcb179de4358 100644
--- a/include/uapi/mtd/ubi-user.h
+++ b/include/uapi/mtd/ubi-user.h
@@ -247,6 +247,7 @@ enum {
* @vid_hdr_offset: VID header offset (use defaults if %0)
* @max_beb_per1024: maximum expected number of bad PEB per 1024 PEBs
* @padding: reserved for future, not used, has to be zeroed
+ * @disable_fm: whether disable fastmap
*
* This data structure is used to specify MTD device UBI has to attach and the
* parameters it has to use. The number which should be assigned to the new UBI
@@ -281,13 +282,18 @@ enum {
* eraseblocks for new bad eraseblocks, but attempts to use available
* eraseblocks (if any). The accepted range is 0-768. If 0 is given, the
* default kernel value of %CONFIG_MTD_UBI_BEB_LIMIT will be used.
+ *
+ * If @disable_fm is not zero, ubi doesn't create new fastmap even the module
+ * param 'fm_autoconvert' is set, and existed old fastmap will be destroyed
+ * after doing full scanning.
*/
struct ubi_attach_req {
__s32 ubi_num;
__s32 mtd_num;
__s32 vid_hdr_offset;
__s16 max_beb_per1024;
- __s8 padding[10];
+ __s8 disable_fm;
+ __s8 padding[9];
};
/*
--
2.31.1