4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Richard Weinberger richard@nod.at
commit fdf10ed710c0aa177e8dfcd84e65e4e5e8e0956b upstream.
Introduce a new list to the UBI attach information object to be able to deal better with old and corrupted Fastmap eraseblocks. Also move more Fastmap specific code into fastmap.c.
Signed-off-by: Richard Weinberger richard@nod.at Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/mtd/ubi/attach.c | 99 ++++++++++++++++++++++++++++++++-------------- drivers/mtd/ubi/fastmap.c | 36 +++++++++++++++- drivers/mtd/ubi/ubi.h | 28 ++++++++++++- drivers/mtd/ubi/wl.c | 41 +++++++++++++++---- 4 files changed, 162 insertions(+), 42 deletions(-)
--- a/drivers/mtd/ubi/attach.c +++ b/drivers/mtd/ubi/attach.c @@ -175,6 +175,40 @@ static int add_corrupted(struct ubi_atta }
/** + * add_fastmap - add a Fastmap related physical eraseblock. + * @ai: attaching information + * @pnum: physical eraseblock number the VID header came from + * @vid_hdr: the volume identifier header + * @ec: erase counter of the physical eraseblock + * + * This function allocates a 'struct ubi_ainf_peb' object for a Fastamp + * physical eraseblock @pnum and adds it to the 'fastmap' list. + * Such blocks can be Fastmap super and data blocks from both the most + * recent Fastmap we're attaching from or from old Fastmaps which will + * be erased. + */ +static int add_fastmap(struct ubi_attach_info *ai, int pnum, + struct ubi_vid_hdr *vid_hdr, int ec) +{ + struct ubi_ainf_peb *aeb; + + aeb = kmem_cache_alloc(ai->aeb_slab_cache, GFP_KERNEL); + if (!aeb) + return -ENOMEM; + + aeb->pnum = pnum; + aeb->vol_id = be32_to_cpu(vidh->vol_id); + aeb->sqnum = be64_to_cpu(vidh->sqnum); + aeb->ec = ec; + list_add(&aeb->u.list, &ai->fastmap); + + dbg_bld("add to fastmap list: PEB %d, vol_id %d, sqnum: %llu", pnum, + aeb->vol_id, aeb->sqnum); + + return 0; +} + +/** * validate_vid_hdr - check volume identifier header. * @ubi: UBI device description object * @vid_hdr: the volume identifier header to check @@ -822,18 +856,15 @@ static bool vol_ignored(int vol_id) * @ubi: UBI device description object * @ai: attaching information * @pnum: the physical eraseblock number - * @vid: The volume ID of the found volume will be stored in this pointer - * @sqnum: The sqnum of the found volume will be stored in this pointer * * This function reads UBI headers of PEB @pnum, checks them, and adds * information about this PEB to the corresponding list or RB-tree in the * "attaching info" structure. Returns zero if the physical eraseblock was * successfully handled and a negative error code in case of failure. */ -static int scan_peb(struct ubi_device *ubi, struct ubi_attach_info *ai, - int pnum, int *vid, unsigned long long *sqnum) +static int scan_peb(struct ubi_device *ubi, struct ubi_attach_info *ai, int pnum) { - long long uninitialized_var(ec); + long long ec; int err, bitflips = 0, vol_id = -1, ec_err = 0;
dbg_bld("scan PEB %d", pnum); @@ -1005,10 +1036,6 @@ static int scan_peb(struct ubi_device *u }
vol_id = be32_to_cpu(vidh->vol_id); - if (vid) - *vid = vol_id; - if (sqnum) - *sqnum = be64_to_cpu(vidh->sqnum); if (vol_id > UBI_MAX_VOLUMES && !vol_ignored(vol_id)) { int lnum = be32_to_cpu(vidh->lnum);
@@ -1049,7 +1076,12 @@ static int scan_peb(struct ubi_device *u if (ec_err) ubi_warn(ubi, "valid VID header but corrupted EC header at PEB %d", pnum); - err = ubi_add_to_av(ubi, ai, pnum, ec, vidh, bitflips); + + if (ubi_is_fm_vol(vol_id)) + err = add_fastmap(ai, pnum, vidh, ec); + else + err = ubi_add_to_av(ubi, ai, pnum, ec, vidh, bitflips); + if (err) return err;
@@ -1198,6 +1230,10 @@ static void destroy_ai(struct ubi_attach list_del(&aeb->u.list); kmem_cache_free(ai->aeb_slab_cache, aeb); } + list_for_each_entry_safe(aeb, aeb_tmp, &ai->fastmap, u.list) { + list_del(&aeb->u.list); + kmem_cache_free(ai->aeb_slab_cache, aeb); + }
/* Destroy the volume RB-tree */ rb = ai->volumes.rb_node; @@ -1257,7 +1293,7 @@ static int scan_all(struct ubi_device *u cond_resched();
dbg_gen("process PEB %d", pnum); - err = scan_peb(ubi, ai, pnum, NULL, NULL); + err = scan_peb(ubi, ai, pnum); if (err < 0) goto out_vidh; } @@ -1323,6 +1359,7 @@ static struct ubi_attach_info *alloc_ai( INIT_LIST_HEAD(&ai->free); INIT_LIST_HEAD(&ai->erase); INIT_LIST_HEAD(&ai->alien); + INIT_LIST_HEAD(&ai->fastmap); ai->volumes = RB_ROOT; ai->aeb_slab_cache = kmem_cache_create("ubi_aeb_slab_cache", sizeof(struct ubi_ainf_peb), @@ -1349,52 +1386,54 @@ static struct ubi_attach_info *alloc_ai( */ static int scan_fast(struct ubi_device *ubi, struct ubi_attach_info **ai) { - int err, pnum, fm_anchor = -1; - unsigned long long max_sqnum = 0; + int err, pnum; + struct ubi_attach_info *scan_ai;
err = -ENOMEM;
+ scan_ai = alloc_ai(); + if (!scan_ai) + goto out; + ech = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL); if (!ech) - goto out; + goto out_ai;
vidh = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL); if (!vidh) goto out_ech;
for (pnum = 0; pnum < UBI_FM_MAX_START; pnum++) { - int vol_id = -1; - unsigned long long sqnum = -1; cond_resched();
dbg_gen("process PEB %d", pnum); - err = scan_peb(ubi, *ai, pnum, &vol_id, &sqnum); + err = scan_peb(ubi, scan_ai, pnum); if (err < 0) goto out_vidh; - - if (vol_id == UBI_FM_SB_VOLUME_ID && sqnum > max_sqnum) { - max_sqnum = sqnum; - fm_anchor = pnum; - } }
ubi_free_vid_hdr(ubi, vidh); kfree(ech);
- if (fm_anchor < 0) - return UBI_NO_FASTMAP; - - destroy_ai(*ai); - *ai = alloc_ai(); - if (!*ai) - return -ENOMEM; + err = ubi_scan_fastmap(ubi, *ai, scan_ai); + if (err) { + /* + * Didn't attach via fastmap, do a full scan but reuse what + * we've aready scanned. + */ + destroy_ai(*ai); + *ai = scan_ai; + } else + destroy_ai(scan_ai);
- return ubi_scan_fastmap(ubi, *ai, fm_anchor); + return err;
out_vidh: ubi_free_vid_hdr(ubi, vidh); out_ech: kfree(ech); +out_ai: + destroy_ai(scan_ai); out: return err; } --- a/drivers/mtd/ubi/fastmap.c +++ b/drivers/mtd/ubi/fastmap.c @@ -851,27 +851,57 @@ fail: }
/** + * find_fm_anchor - find the most recent Fastmap superblock (anchor) + * @ai: UBI attach info to be filled + */ +static int find_fm_anchor(struct ubi_attach_info *ai) +{ + int ret = -1; + struct ubi_ainf_peb *aeb; + unsigned long long max_sqnum = 0; + + list_for_each_entry(aeb, &ai->fastmap, u.list) { + if (aeb->vol_id == UBI_FM_SB_VOLUME_ID && aeb->sqnum > max_sqnum) { + max_sqnum = aeb->sqnum; + ret = aeb->pnum; + } + } + + return ret; +} + +/** * ubi_scan_fastmap - scan the fastmap. * @ubi: UBI device object * @ai: UBI attach info to be filled - * @fm_anchor: The fastmap starts at this PEB + * @scan_ai: UBI attach info from the first 64 PEBs, + * used to find the most recent Fastmap data structure * * Returns 0 on success, UBI_NO_FASTMAP if no fastmap was found, * UBI_BAD_FASTMAP if one was found but is not usable. * < 0 indicates an internal error. */ int ubi_scan_fastmap(struct ubi_device *ubi, struct ubi_attach_info *ai, - int fm_anchor) + struct ubi_attach_info *scan_ai) { struct ubi_fm_sb *fmsb, *fmsb2; struct ubi_vid_hdr *vh; struct ubi_ec_hdr *ech; struct ubi_fastmap_layout *fm; - int i, used_blocks, pnum, ret = 0; + struct ubi_ainf_peb *tmp_aeb, *aeb; + int i, used_blocks, pnum, fm_anchor, ret = 0; size_t fm_size; __be32 crc, tmp_crc; unsigned long long sqnum = 0;
+ fm_anchor = find_fm_anchor(scan_ai); + if (fm_anchor < 0) + return UBI_NO_FASTMAP; + + /* Move all (possible) fastmap blocks into our new attach structure. */ + list_for_each_entry_safe(aeb, tmp_aeb, &scan_ai->fastmap, u.list) + list_move_tail(&aeb->u.list, &ai->fastmap); + down_write(&ubi->fm_protect); memset(ubi->fm_buf, 0, ubi->fm_size);
--- a/drivers/mtd/ubi/ubi.h +++ b/drivers/mtd/ubi/ubi.h @@ -699,6 +699,8 @@ struct ubi_ainf_volume { * @erase: list of physical eraseblocks which have to be erased * @alien: list of physical eraseblocks which should not be used by UBI (e.g., * those belonging to "preserve"-compatible internal volumes) + * @fastmap: list of physical eraseblocks which relate to fastmap (e.g., + * eraseblocks of the current and not yet erased old fastmap blocks) * @corr_peb_count: count of PEBs in the @corr list * @empty_peb_count: count of PEBs which are presumably empty (contain only * 0xFF bytes) @@ -727,6 +729,7 @@ struct ubi_attach_info { struct list_head free; struct list_head erase; struct list_head alien; + struct list_head fastmap; int corr_peb_count; int empty_peb_count; int alien_peb_count; @@ -907,7 +910,7 @@ int ubi_compare_lebs(struct ubi_device * size_t ubi_calc_fm_size(struct ubi_device *ubi); int ubi_update_fastmap(struct ubi_device *ubi); int ubi_scan_fastmap(struct ubi_device *ubi, struct ubi_attach_info *ai, - int fm_anchor); + struct ubi_attach_info *scan_ai); #else static inline int ubi_update_fastmap(struct ubi_device *ubi) { return 0; } #endif @@ -1116,4 +1119,27 @@ static inline bool ubi_is_fm_vol(int vol return false; }
+/** + * ubi_find_fm_block - check whether a PEB is part of the current Fastmap. + * @ubi: UBI device description object + * @pnum: physical eraseblock to look for + * + * This function returns a wear leveling object if @pnum relates to the current + * fastmap, @NULL otherwise. + */ +static inline struct ubi_wl_entry *ubi_find_fm_block(const struct ubi_device *ubi, + int pnum) +{ + int i; + + if (ubi->fm) { + for (i = 0; i < ubi->fm->used_blocks; i++) { + if (ubi->fm->e[i]->pnum == pnum) + return ubi->fm->e[i]; + } + } + + return NULL; +} + #endif /* !__UBI_UBI_H__ */ --- a/drivers/mtd/ubi/wl.c +++ b/drivers/mtd/ubi/wl.c @@ -1598,19 +1598,44 @@ int ubi_wl_init(struct ubi_device *ubi, } }
- dbg_wl("found %i PEBs", found_pebs); + list_for_each_entry(aeb, &ai->fastmap, u.list) { + cond_resched(); + + e = ubi_find_fm_block(ubi, aeb->pnum); + + if (e) { + ubi_assert(!ubi->lookuptbl[e->pnum]); + ubi->lookuptbl[e->pnum] = e; + } else { + /* + * Usually old Fastmap PEBs are scheduled for erasure + * and we don't have to care about them but if we face + * an power cut before scheduling them we need to + * take care of them here. + */ + if (ubi->lookuptbl[aeb->pnum]) + continue;
- if (ubi->fm) { - ubi_assert(ubi->good_peb_count == - found_pebs + ubi->fm->used_blocks); + e = kmem_cache_alloc(ubi_wl_entry_slab, GFP_KERNEL); + if (!e) + goto out_free;
- for (i = 0; i < ubi->fm->used_blocks; i++) { - e = ubi->fm->e[i]; + e->pnum = aeb->pnum; + e->ec = aeb->ec; + ubi_assert(!ubi->lookuptbl[e->pnum]); ubi->lookuptbl[e->pnum] = e; + if (schedule_erase(ubi, e, aeb->vol_id, aeb->lnum, 0)) { + wl_entry_destroy(ubi, e); + goto out_free; + } } + + found_pebs++; } - else - ubi_assert(ubi->good_peb_count == found_pebs); + + dbg_wl("found %i PEBs", found_pebs); + + ubi_assert(ubi->good_peb_count == found_pebs);
reserved_pebs = WL_RESERVED_PEBS; ubi_fastmap_init(ubi, &reserved_pebs);