From 799dca34ac543485f581bd8464ec9b1c4f0f852a Mon Sep 17 00:00:00 2001 From: Boris Brezillon Date: Fri, 16 Sep 2016 16:59:25 +0200 Subject: [PATCH] UBI: hide EBA internals Create a private ubi_eba_table struct to hide EBA internals and provide helpers to allocate, destroy, copy and assing an EBA table to a volume. Now that external EBA users are using helpers to query/modify the EBA state we can safely change the internal representation, which will be needed to support the LEB consolidation concept. Signed-off-by: Boris Brezillon Signed-off-by: Richard Weinberger --- drivers/mtd/ubi/build.c | 2 +- drivers/mtd/ubi/eba.c | 166 +++++++++++++++++++++++++++++++++------- drivers/mtd/ubi/ubi.h | 8 +- drivers/mtd/ubi/vmt.c | 40 ++++------ 4 files changed, 165 insertions(+), 51 deletions(-) diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c index 0680516bb472..85d54f37e28f 100644 --- a/drivers/mtd/ubi/build.c +++ b/drivers/mtd/ubi/build.c @@ -574,7 +574,7 @@ void ubi_free_internal_volumes(struct ubi_device *ubi) for (i = ubi->vtbl_slots; i < ubi->vtbl_slots + UBI_INT_VOL_COUNT; i++) { - kfree(ubi->volumes[i]->eba_tbl); + ubi_eba_replace_table(ubi->volumes[i], NULL); kfree(ubi->volumes[i]); } } diff --git a/drivers/mtd/ubi/eba.c b/drivers/mtd/ubi/eba.c index f3ff8604b5e5..884c91ffe7ba 100644 --- a/drivers/mtd/ubi/eba.c +++ b/drivers/mtd/ubi/eba.c @@ -49,6 +49,30 @@ /* Number of physical eraseblocks reserved for atomic LEB change operation */ #define EBA_RESERVED_PEBS 1 +/** + * struct ubi_eba_entry - structure encoding a single LEB -> PEB association + * @pnum: the physical eraseblock number attached to the LEB + * + * This structure is encoding a LEB -> PEB association. Note that the LEB + * number is not stored here, because it is the index used to access the + * entries table. + */ +struct ubi_eba_entry { + int pnum; +}; + +/** + * struct ubi_eba_table - LEB -> PEB association information + * @entries: the LEB to PEB mapping (one entry per LEB). + * + * This structure is private to the EBA logic and should be kept here. + * It is encoding the LEB to PEB association table, and is subject to + * changes. + */ +struct ubi_eba_table { + struct ubi_eba_entry *entries; +}; + /** * next_sqnum - get next sequence number. * @ubi: UBI device description object @@ -97,7 +121,94 @@ void ubi_eba_get_ldesc(struct ubi_volume *vol, int lnum, struct ubi_eba_leb_desc *ldesc) { ldesc->lnum = lnum; - ldesc->pnum = vol->eba_tbl[lnum]; + ldesc->pnum = vol->eba_tbl->entries[lnum].pnum; +} + +/** + * ubi_eba_create_table - allocate a new EBA table and initialize it with all + * LEBs unmapped + * @vol: volume containing the EBA table to copy + * @nentries: number of entries in the table + * + * Allocate a new EBA table and initialize it with all LEBs unmapped. + * Returns a valid pointer if it succeed, an ERR_PTR() otherwise. + */ +struct ubi_eba_table *ubi_eba_create_table(struct ubi_volume *vol, + int nentries) +{ + struct ubi_eba_table *tbl; + int err = -ENOMEM; + int i; + + tbl = kzalloc(sizeof(*tbl), GFP_KERNEL); + if (!tbl) + return ERR_PTR(-ENOMEM); + + tbl->entries = kmalloc_array(nentries, sizeof(*tbl->entries), + GFP_KERNEL); + if (!tbl->entries) + goto err; + + for (i = 0; i < nentries; i++) + tbl->entries[i].pnum = UBI_LEB_UNMAPPED; + + return tbl; + +err: + kfree(tbl->entries); + kfree(tbl); + + return ERR_PTR(err); +} + +/** + * ubi_eba_destroy_table - destroy an EBA table + * @tbl: the table to destroy + * + * Destroy an EBA table. + */ +void ubi_eba_destroy_table(struct ubi_eba_table *tbl) +{ + if (!tbl) + return; + + kfree(tbl->entries); + kfree(tbl); +} + +/** + * ubi_eba_copy_table - copy the EBA table attached to vol into another table + * @vol: volume containing the EBA table to copy + * @dst: destination + * @nentries: number of entries to copy + * + * Copy the EBA table stored in vol into the one pointed by dst. + */ +void ubi_eba_copy_table(struct ubi_volume *vol, struct ubi_eba_table *dst, + int nentries) +{ + struct ubi_eba_table *src; + int i; + + ubi_assert(dst && vol && vol->eba_tbl); + + src = vol->eba_tbl; + + for (i = 0; i < nentries; i++) + dst->entries[i].pnum = src->entries[i].pnum; +} + +/** + * ubi_eba_replace_table - assign a new EBA table to a volume + * @vol: volume containing the EBA table to copy + * @tbl: new EBA table + * + * Assign a new EBA table to the volume and release the old one. + */ +void ubi_eba_replace_table(struct ubi_volume *vol, struct ubi_eba_table *tbl) +{ + ubi_eba_destroy_table(vol->eba_tbl); + vol->eba_tbl = tbl; } /** @@ -337,7 +448,7 @@ static void leb_write_unlock(struct ubi_device *ubi, int vol_id, int lnum) */ bool ubi_eba_is_mapped(struct ubi_volume *vol, int lnum) { - return vol->eba_tbl[lnum] >= 0; + return vol->eba_tbl->entries[lnum].pnum >= 0; } /** @@ -362,7 +473,7 @@ int ubi_eba_unmap_leb(struct ubi_device *ubi, struct ubi_volume *vol, if (err) return err; - pnum = vol->eba_tbl[lnum]; + pnum = vol->eba_tbl->entries[lnum].pnum; if (pnum < 0) /* This logical eraseblock is already unmapped */ goto out_unlock; @@ -370,7 +481,7 @@ int ubi_eba_unmap_leb(struct ubi_device *ubi, struct ubi_volume *vol, dbg_eba("erase LEB %d:%d, PEB %d", vol_id, lnum, pnum); down_read(&ubi->fm_eba_sem); - vol->eba_tbl[lnum] = UBI_LEB_UNMAPPED; + vol->eba_tbl->entries[lnum].pnum = UBI_LEB_UNMAPPED; up_read(&ubi->fm_eba_sem); err = ubi_wl_put_peb(ubi, vol_id, lnum, pnum, 0); @@ -409,7 +520,7 @@ int ubi_eba_read_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum, if (err) return err; - pnum = vol->eba_tbl[lnum]; + pnum = vol->eba_tbl->entries[lnum].pnum; if (pnum < 0) { /* * The logical eraseblock is not mapped, fill the whole buffer @@ -658,7 +769,7 @@ out_unlock: mutex_unlock(&ubi->buf_mutex); if (!err) - vol->eba_tbl[lnum] = new_pnum; + vol->eba_tbl->entries[lnum].pnum = new_pnum; out_put: up_read(&ubi->fm_eba_sem); @@ -749,7 +860,7 @@ static int try_write_vid_and_data(struct ubi_volume *vol, int lnum, goto out_put; } - opnum = vol->eba_tbl[lnum]; + opnum = vol->eba_tbl->entries[lnum].pnum; dbg_eba("write VID hdr and %d bytes at offset %d of LEB %d:%d, PEB %d", len, offset, vol_id, lnum, pnum); @@ -771,7 +882,7 @@ static int try_write_vid_and_data(struct ubi_volume *vol, int lnum, } } - vol->eba_tbl[lnum] = pnum; + vol->eba_tbl->entries[lnum].pnum = pnum; out_put: up_read(&ubi->fm_eba_sem); @@ -812,7 +923,7 @@ int ubi_eba_write_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum, if (err) return err; - pnum = vol->eba_tbl[lnum]; + pnum = vol->eba_tbl->entries[lnum].pnum; if (pnum >= 0) { dbg_eba("write %d bytes at offset %d of LEB %d:%d, PEB %d", len, offset, vol_id, lnum, pnum); @@ -930,7 +1041,7 @@ int ubi_eba_write_leb_st(struct ubi_device *ubi, struct ubi_volume *vol, vid_hdr->used_ebs = cpu_to_be32(used_ebs); vid_hdr->data_crc = cpu_to_be32(crc); - ubi_assert(vol->eba_tbl[lnum] < 0); + ubi_assert(vol->eba_tbl->entries[lnum].pnum < 0); for (tries = 0; tries <= UBI_IO_RETRIES; tries++) { err = try_write_vid_and_data(vol, lnum, vid_hdr, buf, 0, len); @@ -1140,9 +1251,9 @@ int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to, * probably waiting on @ubi->move_mutex. No need to continue the work, * cancel it. */ - if (vol->eba_tbl[lnum] != from) { + if (vol->eba_tbl->entries[lnum].pnum != from) { dbg_wl("LEB %d:%d is no longer mapped to PEB %d, mapped to PEB %d, cancel", - vol_id, lnum, from, vol->eba_tbl[lnum]); + vol_id, lnum, from, vol->eba_tbl->entries[lnum].pnum); err = MOVE_CANCEL_RACE; goto out_unlock_leb; } @@ -1227,9 +1338,9 @@ int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to, cond_resched(); } - ubi_assert(vol->eba_tbl[lnum] == from); + ubi_assert(vol->eba_tbl->entries[lnum].pnum == from); down_read(&ubi->fm_eba_sem); - vol->eba_tbl[lnum] = to; + vol->eba_tbl->entries[lnum].pnum = to; up_read(&ubi->fm_eba_sem); out_unlock_buf: @@ -1386,7 +1497,7 @@ out_free: */ int ubi_eba_init(struct ubi_device *ubi, struct ubi_attach_info *ai) { - int i, j, err, num_volumes; + int i, err, num_volumes; struct ubi_ainf_volume *av; struct ubi_volume *vol; struct ubi_ainf_peb *aeb; @@ -1402,35 +1513,39 @@ int ubi_eba_init(struct ubi_device *ubi, struct ubi_attach_info *ai) num_volumes = ubi->vtbl_slots + UBI_INT_VOL_COUNT; for (i = 0; i < num_volumes; i++) { + struct ubi_eba_table *tbl; + vol = ubi->volumes[i]; if (!vol) continue; cond_resched(); - vol->eba_tbl = kmalloc(vol->reserved_pebs * sizeof(int), - GFP_KERNEL); - if (!vol->eba_tbl) { - err = -ENOMEM; + tbl = ubi_eba_create_table(vol, vol->reserved_pebs); + if (IS_ERR(tbl)) { + err = PTR_ERR(tbl); goto out_free; } - for (j = 0; j < vol->reserved_pebs; j++) - vol->eba_tbl[j] = UBI_LEB_UNMAPPED; + ubi_eba_replace_table(vol, tbl); av = ubi_find_av(ai, idx2vol_id(ubi, i)); if (!av) continue; ubi_rb_for_each_entry(rb, aeb, &av->root, u.rb) { - if (aeb->lnum >= vol->reserved_pebs) + if (aeb->lnum >= vol->reserved_pebs) { /* * This may happen in case of an unclean reboot * during re-size. */ ubi_move_aeb_to_list(av, aeb, &ai->erase); - else - vol->eba_tbl[aeb->lnum] = aeb->pnum; + } else { + struct ubi_eba_entry *entry; + + entry = &vol->eba_tbl->entries[aeb->lnum]; + entry->pnum = aeb->pnum; + } } } @@ -1467,8 +1582,7 @@ out_free: for (i = 0; i < num_volumes; i++) { if (!ubi->volumes[i]) continue; - kfree(ubi->volumes[i]->eba_tbl); - ubi->volumes[i]->eba_tbl = NULL; + ubi_eba_replace_table(ubi->volumes[i], NULL); } return err; } diff --git a/drivers/mtd/ubi/ubi.h b/drivers/mtd/ubi/ubi.h index 98e5dac677ee..bc145229a53c 100644 --- a/drivers/mtd/ubi/ubi.h +++ b/drivers/mtd/ubi/ubi.h @@ -359,7 +359,7 @@ struct ubi_volume { long long upd_received; void *upd_buf; - int *eba_tbl; + struct ubi_eba_table *eba_tbl; unsigned int checked:1; unsigned int corrupted:1; unsigned int upd_marker:1; @@ -864,6 +864,12 @@ static inline bool ubi_leb_valid(struct ubi_volume *vol, int lnum) } /* eba.c */ +struct ubi_eba_table *ubi_eba_create_table(struct ubi_volume *vol, + int nentries); +void ubi_eba_destroy_table(struct ubi_eba_table *tbl); +void ubi_eba_copy_table(struct ubi_volume *vol, struct ubi_eba_table *dst, + int nentries); +void ubi_eba_replace_table(struct ubi_volume *vol, struct ubi_eba_table *tbl); void ubi_eba_get_ldesc(struct ubi_volume *vol, int lnum, struct ubi_eba_leb_desc *ldesc); bool ubi_eba_is_mapped(struct ubi_volume *vol, int lnum); diff --git a/drivers/mtd/ubi/vmt.c b/drivers/mtd/ubi/vmt.c index 0138f526474a..7ac78c13dd1c 100644 --- a/drivers/mtd/ubi/vmt.c +++ b/drivers/mtd/ubi/vmt.c @@ -138,7 +138,7 @@ static void vol_release(struct device *dev) { struct ubi_volume *vol = container_of(dev, struct ubi_volume, dev); - kfree(vol->eba_tbl); + ubi_eba_replace_table(vol, NULL); kfree(vol); } @@ -158,6 +158,7 @@ int ubi_create_volume(struct ubi_device *ubi, struct ubi_mkvol_req *req) int i, err, vol_id = req->vol_id, do_free = 1; struct ubi_volume *vol; struct ubi_vtbl_record vtbl_rec; + struct ubi_eba_table *eba_tbl = NULL; dev_t dev; if (ubi->ro_mode) @@ -241,14 +242,13 @@ int ubi_create_volume(struct ubi_device *ubi, struct ubi_mkvol_req *req) if (err) goto out_acc; - vol->eba_tbl = kmalloc(vol->reserved_pebs * sizeof(int), GFP_KERNEL); - if (!vol->eba_tbl) { - err = -ENOMEM; + eba_tbl = ubi_eba_create_table(vol, vol->reserved_pebs); + if (IS_ERR(eba_tbl)) { + err = PTR_ERR(eba_tbl); goto out_acc; } - for (i = 0; i < vol->reserved_pebs; i++) - vol->eba_tbl[i] = UBI_LEB_UNMAPPED; + ubi_eba_replace_table(vol, eba_tbl); if (vol->vol_type == UBI_DYNAMIC_VOLUME) { vol->used_ebs = vol->reserved_pebs; @@ -329,7 +329,7 @@ out_cdev: cdev_del(&vol->cdev); out_mapping: if (do_free) - kfree(vol->eba_tbl); + ubi_eba_destroy_table(eba_tbl); out_acc: spin_lock(&ubi->volumes_lock); ubi->rsvd_pebs -= vol->reserved_pebs; @@ -427,10 +427,11 @@ out_unlock: */ int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs) { - int i, err, pebs, *new_mapping; + int i, err, pebs; struct ubi_volume *vol = desc->vol; struct ubi_device *ubi = vol->ubi; struct ubi_vtbl_record vtbl_rec; + struct ubi_eba_table *new_eba_tbl = NULL; int vol_id = vol->vol_id; if (ubi->ro_mode) @@ -450,12 +451,9 @@ int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs) if (reserved_pebs == vol->reserved_pebs) return 0; - new_mapping = kmalloc(reserved_pebs * sizeof(int), GFP_KERNEL); - if (!new_mapping) - return -ENOMEM; - - for (i = 0; i < reserved_pebs; i++) - new_mapping[i] = UBI_LEB_UNMAPPED; + new_eba_tbl = ubi_eba_create_table(vol, reserved_pebs); + if (IS_ERR(new_eba_tbl)) + return PTR_ERR(new_eba_tbl); spin_lock(&ubi->volumes_lock); if (vol->ref_count > 1) { @@ -481,10 +479,8 @@ int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs) } ubi->avail_pebs -= pebs; ubi->rsvd_pebs += pebs; - for (i = 0; i < vol->reserved_pebs; i++) - new_mapping[i] = vol->eba_tbl[i]; - kfree(vol->eba_tbl); - vol->eba_tbl = new_mapping; + ubi_eba_copy_table(vol, new_eba_tbl, vol->reserved_pebs); + ubi_eba_replace_table(vol, new_eba_tbl); spin_unlock(&ubi->volumes_lock); } @@ -498,10 +494,8 @@ int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs) ubi->rsvd_pebs += pebs; ubi->avail_pebs -= pebs; ubi_update_reserved(ubi); - for (i = 0; i < reserved_pebs; i++) - new_mapping[i] = vol->eba_tbl[i]; - kfree(vol->eba_tbl); - vol->eba_tbl = new_mapping; + ubi_eba_copy_table(vol, new_eba_tbl, reserved_pebs); + ubi_eba_replace_table(vol, new_eba_tbl); spin_unlock(&ubi->volumes_lock); } @@ -543,7 +537,7 @@ out_acc: spin_unlock(&ubi->volumes_lock); } out_free: - kfree(new_mapping); + kfree(new_eba_tbl); return err; }