From: Zhihao Cheng chengzhihao1@huawei.com
mainline inclusion from mainline-v6.1-rc1 commit 669d204469c46e91d99da24914130f78277a71d3 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I5WQRM CVE: NA
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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[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 chengzhihao1@huawei.com Signed-off-by: Richard Weinberger richard@nod.at Reviewed-by: Zhihao Cheng chengzhihao1@huawei.com Reviewed-by: Zhang Yi yi.zhang@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com --- 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 4153e0d15c5f..ac97f6f9bcc2 100644 --- a/drivers/mtd/ubi/build.c +++ b/drivers/mtd/ubi/build.c @@ -808,6 +808,7 @@ 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 @@ -815,11 +816,15 @@ 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; @@ -922,7 +927,7 @@ 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);
@@ -963,7 +968,7 @@ 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); @@ -1243,7 +1248,8 @@ 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 da0bee13fe7f..4f84607dafb4 100644 --- a/drivers/mtd/ubi/ubi.h +++ b/drivers/mtd/ubi/ubi.h @@ -939,7 +939,8 @@ 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]; };
/*