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commit a840b56ba385059742c2b7f4fd665ec9afb8931e
parent ebc551f2b8f905eca0e25c476c1e5c098cd92103
Author: Linus Torvalds <torvalds@linux-foundation.org>
Date:   Wed, 13 Mar 2019 09:34:35 -0700

Merge tag 'upstream-5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs

Pull UBI and UBIFS updates from Richard Weinberger:

 - A new interface for UBI to deal better with read disturb

 - Reject unsupported ioctl flags in UBIFS (xfstests found it)

* tag 'upstream-5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs:
  ubi: wl: Silence uninitialized variable warning
  ubifs: Reject unsupported ioctl flags explicitly
  ubi: Expose the bitrot interface
  ubi: Introduce in_pq()

Diffstat:
Mdrivers/mtd/ubi/cdev.c | 30++++++++++++++++++++++++++++++
Mdrivers/mtd/ubi/ubi.h | 1+
Mdrivers/mtd/ubi/wl.c | 174+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++----
Mfs/ubifs/ioctl.c | 8++++++++
Minclude/uapi/mtd/ubi-user.h | 5+++++
5 files changed, 211 insertions(+), 7 deletions(-)

diff --git a/drivers/mtd/ubi/cdev.c b/drivers/mtd/ubi/cdev.c @@ -974,6 +974,36 @@ static long ubi_cdev_ioctl(struct file *file, unsigned int cmd, break; } + /* Check a specific PEB for bitflips and scrub it if needed */ + case UBI_IOCRPEB: + { + int pnum; + + err = get_user(pnum, (__user int32_t *)argp); + if (err) { + err = -EFAULT; + break; + } + + err = ubi_bitflip_check(ubi, pnum, 0); + break; + } + + /* Force scrubbing for a specific PEB */ + case UBI_IOCSPEB: + { + int pnum; + + err = get_user(pnum, (__user int32_t *)argp); + if (err) { + err = -EFAULT; + break; + } + + err = ubi_bitflip_check(ubi, pnum, 1); + break; + } + default: err = -ENOTTY; break; diff --git a/drivers/mtd/ubi/ubi.h b/drivers/mtd/ubi/ubi.h @@ -929,6 +929,7 @@ int ubi_wl_put_fm_peb(struct ubi_device *ubi, struct ubi_wl_entry *used_e, int ubi_is_erase_work(struct ubi_work *wrk); void ubi_refill_pools(struct ubi_device *ubi); int ubi_ensure_anchor_pebs(struct ubi_device *ubi); +int ubi_bitflip_check(struct ubi_device *ubi, int pnum, int force_scrub); /* io.c */ int ubi_io_read(const struct ubi_device *ubi, void *buf, int pnum, int offset, diff --git a/drivers/mtd/ubi/wl.c b/drivers/mtd/ubi/wl.c @@ -278,6 +278,27 @@ static int in_wl_tree(struct ubi_wl_entry *e, struct rb_root *root) } /** + * in_pq - check if a wear-leveling entry is present in the protection queue. + * @ubi: UBI device description object + * @e: the wear-leveling entry to check + * + * This function returns non-zero if @e is in the protection queue and zero + * if it is not. + */ +static inline int in_pq(const struct ubi_device *ubi, struct ubi_wl_entry *e) +{ + struct ubi_wl_entry *p; + int i; + + for (i = 0; i < UBI_PROT_QUEUE_LEN; ++i) + list_for_each_entry(p, &ubi->pq[i], u.list) + if (p == e) + return 1; + + return 0; +} + +/** * prot_queue_add - add physical eraseblock to the protection queue. * @ubi: UBI device description object * @e: the physical eraseblock to add @@ -1419,6 +1440,150 @@ int ubi_wl_flush(struct ubi_device *ubi, int vol_id, int lnum) return err; } +static bool scrub_possible(struct ubi_device *ubi, struct ubi_wl_entry *e) +{ + if (in_wl_tree(e, &ubi->scrub)) + return false; + else if (in_wl_tree(e, &ubi->erroneous)) + return false; + else if (ubi->move_from == e) + return false; + else if (ubi->move_to == e) + return false; + + return true; +} + +/** + * ubi_bitflip_check - Check an eraseblock for bitflips and scrub it if needed. + * @ubi: UBI device description object + * @pnum: the physical eraseblock to schedule + * @force: dont't read the block, assume bitflips happened and take action. + * + * This function reads the given eraseblock and checks if bitflips occured. + * In case of bitflips, the eraseblock is scheduled for scrubbing. + * If scrubbing is forced with @force, the eraseblock is not read, + * but scheduled for scrubbing right away. + * + * Returns: + * %EINVAL, PEB is out of range + * %ENOENT, PEB is no longer used by UBI + * %EBUSY, PEB cannot be checked now or a check is currently running on it + * %EAGAIN, bit flips happened but scrubbing is currently not possible + * %EUCLEAN, bit flips happened and PEB is scheduled for scrubbing + * %0, no bit flips detected + */ +int ubi_bitflip_check(struct ubi_device *ubi, int pnum, int force) +{ + int err; + struct ubi_wl_entry *e; + + if (pnum < 0 || pnum >= ubi->peb_count) { + err = -EINVAL; + goto out; + } + + /* + * Pause all parallel work, otherwise it can happen that the + * erase worker frees a wl entry under us. + */ + down_write(&ubi->work_sem); + + /* + * Make sure that the wl entry does not change state while + * inspecting it. + */ + spin_lock(&ubi->wl_lock); + e = ubi->lookuptbl[pnum]; + if (!e) { + spin_unlock(&ubi->wl_lock); + err = -ENOENT; + goto out_resume; + } + + /* + * Does it make sense to check this PEB? + */ + if (!scrub_possible(ubi, e)) { + spin_unlock(&ubi->wl_lock); + err = -EBUSY; + goto out_resume; + } + spin_unlock(&ubi->wl_lock); + + if (!force) { + mutex_lock(&ubi->buf_mutex); + err = ubi_io_read(ubi, ubi->peb_buf, pnum, 0, ubi->peb_size); + mutex_unlock(&ubi->buf_mutex); + } + + if (force || err == UBI_IO_BITFLIPS) { + /* + * Okay, bit flip happened, let's figure out what we can do. + */ + spin_lock(&ubi->wl_lock); + + /* + * Recheck. We released wl_lock, UBI might have killed the + * wl entry under us. + */ + e = ubi->lookuptbl[pnum]; + if (!e) { + spin_unlock(&ubi->wl_lock); + err = -ENOENT; + goto out_resume; + } + + /* + * Need to re-check state + */ + if (!scrub_possible(ubi, e)) { + spin_unlock(&ubi->wl_lock); + err = -EBUSY; + goto out_resume; + } + + if (in_pq(ubi, e)) { + prot_queue_del(ubi, e->pnum); + wl_tree_add(e, &ubi->scrub); + spin_unlock(&ubi->wl_lock); + + err = ensure_wear_leveling(ubi, 1); + } else if (in_wl_tree(e, &ubi->used)) { + rb_erase(&e->u.rb, &ubi->used); + wl_tree_add(e, &ubi->scrub); + spin_unlock(&ubi->wl_lock); + + err = ensure_wear_leveling(ubi, 1); + } else if (in_wl_tree(e, &ubi->free)) { + rb_erase(&e->u.rb, &ubi->free); + ubi->free_count--; + spin_unlock(&ubi->wl_lock); + + /* + * This PEB is empty we can schedule it for + * erasure right away. No wear leveling needed. + */ + err = schedule_erase(ubi, e, UBI_UNKNOWN, UBI_UNKNOWN, + force ? 0 : 1, true); + } else { + spin_unlock(&ubi->wl_lock); + err = -EAGAIN; + } + + if (!err && !force) + err = -EUCLEAN; + } else { + err = 0; + } + +out_resume: + up_write(&ubi->work_sem); +out: + + return err; +} + /** * tree_destroy - destroy an RB-tree. * @ubi: UBI device description object @@ -1848,16 +2013,11 @@ static int self_check_in_wl_tree(const struct ubi_device *ubi, static int self_check_in_pq(const struct ubi_device *ubi, struct ubi_wl_entry *e) { - struct ubi_wl_entry *p; - int i; - if (!ubi_dbg_chk_gen(ubi)) return 0; - for (i = 0; i < UBI_PROT_QUEUE_LEN; ++i) - list_for_each_entry(p, &ubi->pq[i], u.list) - if (p == e) - return 0; + if (in_pq(ubi, e)) + return 0; ubi_err(ubi, "self-check failed for PEB %d, EC %d, Protect queue", e->pnum, e->ec); diff --git a/fs/ubifs/ioctl.c b/fs/ubifs/ioctl.c @@ -28,6 +28,11 @@ #include <linux/mount.h> #include "ubifs.h" +/* Need to be kept consistent with checked flags in ioctl2ubifs() */ +#define UBIFS_SUPPORTED_IOCTL_FLAGS \ + (FS_COMPR_FL | FS_SYNC_FL | FS_APPEND_FL | \ + FS_IMMUTABLE_FL | FS_DIRSYNC_FL) + /** * ubifs_set_inode_flags - set VFS inode flags. * @inode: VFS inode to set flags for @@ -169,6 +174,9 @@ long ubifs_ioctl(struct file *file, unsigned int cmd, unsigned long arg) if (get_user(flags, (int __user *) arg)) return -EFAULT; + if (flags & ~UBIFS_SUPPORTED_IOCTL_FLAGS) + return -EOPNOTSUPP; + if (!S_ISDIR(inode->i_mode)) flags &= ~FS_DIRSYNC_FL; diff --git a/include/uapi/mtd/ubi-user.h b/include/uapi/mtd/ubi-user.h @@ -171,6 +171,11 @@ /* Re-name volumes */ #define UBI_IOCRNVOL _IOW(UBI_IOC_MAGIC, 3, struct ubi_rnvol_req) +/* Read the specified PEB and scrub it if there are bitflips */ +#define UBI_IOCRPEB _IOW(UBI_IOC_MAGIC, 4, __s32) +/* Force scrubbing on the specified PEB */ +#define UBI_IOCSPEB _IOW(UBI_IOC_MAGIC, 5, __s32) + /* ioctl commands of the UBI control character device */ #define UBI_CTRL_IOC_MAGIC 'o'