Orange Pi5 kernel

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (c) 2012 Linutronix GmbH
 * Copyright (c) 2014 sigma star gmbh
 * Author: Richard Weinberger <richard@nod.at>
 */
 
/**
 * update_fastmap_work_fn - calls ubi_update_fastmap from a work queue
 * @wrk: the work description object
 */
static void update_fastmap_work_fn(struct work_struct *wrk)
{
<------>struct ubi_device *ubi = container_of(wrk, struct ubi_device, fm_work);
 
<------>ubi_update_fastmap(ubi);
<------>spin_lock(&ubi->wl_lock);
<------>ubi->fm_work_scheduled = 0;
<------>spin_unlock(&ubi->wl_lock);
}
 
/**
 * find_anchor_wl_entry - find wear-leveling entry to used as anchor PEB.
 * @root: the RB-tree where to look for
 */
static struct ubi_wl_entry *find_anchor_wl_entry(struct rb_root *root)
{
<------>struct rb_node *p;
<------>struct ubi_wl_entry *e, *victim = NULL;
<------>int max_ec = UBI_MAX_ERASECOUNTER;
 
<------>ubi_rb_for_each_entry(p, e, root, u.rb) {
<------><------>if (e->pnum < UBI_FM_MAX_START && e->ec < max_ec) {
<------><------><------>victim = e;
<------><------><------>max_ec = e->ec;
<------><------>}
<------>}
 
<------>return victim;
}
 
static inline void return_unused_peb(struct ubi_device *ubi,
<------><------><------><------>     struct ubi_wl_entry *e)
{
<------>wl_tree_add(e, &ubi->free);
<------>ubi->free_count++;
}
 
/**
 * return_unused_pool_pebs - returns unused PEB to the free tree.
 * @ubi: UBI device description object
 * @pool: fastmap pool description object
 */
static void return_unused_pool_pebs(struct ubi_device *ubi,
<------><------><------><------>    struct ubi_fm_pool *pool)
{
<------>int i;
<------>struct ubi_wl_entry *e;
 
<------>for (i = pool->used; i < pool->size; i++) {
<------><------>e = ubi->lookuptbl[pool->pebs[i]];
<------><------>return_unused_peb(ubi, e);
<------>}
}
 
/**
 * ubi_wl_get_fm_peb - find a physical erase block with a given maximal number.
 * @ubi: UBI device description object
 * @anchor: This PEB will be used as anchor PEB by fastmap
 *
 * The function returns a physical erase block with a given maximal number
 * and removes it from the wl subsystem.
 * Must be called with wl_lock held!
 */
struct ubi_wl_entry *ubi_wl_get_fm_peb(struct ubi_device *ubi, int anchor)
{
<------>struct ubi_wl_entry *e = NULL;
 
<------>if (!ubi->free.rb_node || (ubi->free_count - ubi->beb_rsvd_pebs < 1))
<------><------>goto out;
 
<------>if (anchor)
<------><------>e = find_anchor_wl_entry(&ubi->free);
<------>else
<------><------>e = find_mean_wl_entry(ubi, &ubi->free);
 
<------>if (!e)
<------><------>goto out;
 
<------>self_check_in_wl_tree(ubi, e, &ubi->free);
 
<------>/* remove it from the free list,
<------> * the wl subsystem does no longer know this erase block */
<------>rb_erase(&e->u.rb, &ubi->free);
<------>ubi->free_count--;
out:
<------>return e;
}
 
/**
 * ubi_refill_pools - refills all fastmap PEB pools.
 * @ubi: UBI device description object
 */
void ubi_refill_pools(struct ubi_device *ubi)
{
<------>struct ubi_fm_pool *wl_pool = &ubi->fm_wl_pool;
<------>struct ubi_fm_pool *pool = &ubi->fm_pool;
<------>struct ubi_wl_entry *e;
<------>int enough;
 
<------>spin_lock(&ubi->wl_lock);
 
<------>return_unused_pool_pebs(ubi, wl_pool);
<------>return_unused_pool_pebs(ubi, pool);
 
<------>wl_pool->size = 0;
<------>pool->size = 0;
 
<------>if (ubi->fm_anchor) {
<------><------>wl_tree_add(ubi->fm_anchor, &ubi->free);
<------><------>ubi->free_count++;
<------>}
<------>if (ubi->fm_next_anchor) {
<------><------>wl_tree_add(ubi->fm_next_anchor, &ubi->free);
<------><------>ubi->free_count++;
<------>}
 
<------>/* All available PEBs are in ubi->free, now is the time to get
<------> * the best anchor PEBs.
<------> */
<------>ubi->fm_anchor = ubi_wl_get_fm_peb(ubi, 1);
<------>ubi->fm_next_anchor = ubi_wl_get_fm_peb(ubi, 1);
 
<------>for (;;) {
<------><------>enough = 0;
<------><------>if (pool->size < pool->max_size) {
<------><------><------>if (!ubi->free.rb_node)
<------><------><------><------>break;
 
<------><------><------>e = wl_get_wle(ubi);
<------><------><------>if (!e)
<------><------><------><------>break;
 
<------><------><------>pool->pebs[pool->size] = e->pnum;
<------><------><------>pool->size++;
<------><------>} else
<------><------><------>enough++;
 
<------><------>if (wl_pool->size < wl_pool->max_size) {
<------><------><------>if (!ubi->free.rb_node ||
<------><------><------>   (ubi->free_count - ubi->beb_rsvd_pebs < 5))
<------><------><------><------>break;
 
<------><------><------>e = find_wl_entry(ubi, &ubi->free, WL_FREE_MAX_DIFF);
<------><------><------>self_check_in_wl_tree(ubi, e, &ubi->free);
<------><------><------>rb_erase(&e->u.rb, &ubi->free);
<------><------><------>ubi->free_count--;
 
<------><------><------>wl_pool->pebs[wl_pool->size] = e->pnum;
<------><------><------>wl_pool->size++;
<------><------>} else
<------><------><------>enough++;
 
<------><------>if (enough == 2)
<------><------><------>break;
<------>}
 
<------>wl_pool->used = 0;
<------>pool->used = 0;
 
<------>spin_unlock(&ubi->wl_lock);
}
 
/**
 * produce_free_peb - produce a free physical eraseblock.
 * @ubi: UBI device description object
 *
 * This function tries to make a free PEB by means of synchronous execution of
 * pending works. This may be needed if, for example the background thread is
 * disabled. Returns zero in case of success and a negative error code in case
 * of failure.
 */
static int produce_free_peb(struct ubi_device *ubi)
{
<------>int err;
 
<------>while (!ubi->free.rb_node && ubi->works_count) {
<------><------>dbg_wl("do one work synchronously");
<------><------>err = do_work(ubi);
 
<------><------>if (err)
<------><------><------>return err;
<------>}
 
<------>return 0;
}
 
/**
 * ubi_wl_get_peb - get a physical eraseblock.
 * @ubi: UBI device description object
 *
 * This function returns a physical eraseblock in case of success and a
 * negative error code in case of failure.
 * Returns with ubi->fm_eba_sem held in read mode!
 */
int ubi_wl_get_peb(struct ubi_device *ubi)
{
<------>int ret, attempts = 0;
<------>struct ubi_fm_pool *pool = &ubi->fm_pool;
<------>struct ubi_fm_pool *wl_pool = &ubi->fm_wl_pool;
 
again:
<------>down_read(&ubi->fm_eba_sem);
<------>spin_lock(&ubi->wl_lock);
 
<------>/* We check here also for the WL pool because at this point we can
<------> * refill the WL pool synchronous. */
<------>if (pool->used == pool->size || wl_pool->used == wl_pool->size) {
<------><------>spin_unlock(&ubi->wl_lock);
<------><------>up_read(&ubi->fm_eba_sem);
<------><------>ret = ubi_update_fastmap(ubi);
<------><------>if (ret) {
<------><------><------>ubi_msg(ubi, "Unable to write a new fastmap: %i", ret);
<------><------><------>down_read(&ubi->fm_eba_sem);
<------><------><------>return -ENOSPC;
<------><------>}
<------><------>down_read(&ubi->fm_eba_sem);
<------><------>spin_lock(&ubi->wl_lock);
<------>}
 
<------>if (pool->used == pool->size) {
<------><------>spin_unlock(&ubi->wl_lock);
<------><------>attempts++;
<------><------>if (attempts == 10) {
<------><------><------>ubi_err(ubi, "Unable to get a free PEB from user WL pool");
<------><------><------>ret = -ENOSPC;
<------><------><------>goto out;
<------><------>}
<------><------>up_read(&ubi->fm_eba_sem);
<------><------>ret = produce_free_peb(ubi);
<------><------>if (ret < 0) {
<------><------><------>down_read(&ubi->fm_eba_sem);
<------><------><------>goto out;
<------><------>}
<------><------>goto again;
<------>}
 
<------>ubi_assert(pool->used < pool->size);
<------>ret = pool->pebs[pool->used++];
<------>prot_queue_add(ubi, ubi->lookuptbl[ret]);
<------>spin_unlock(&ubi->wl_lock);
out:
<------>return ret;
}
 
/* get_peb_for_wl - returns a PEB to be used internally by the WL sub-system.
 *
 * @ubi: UBI device description object
 */
static struct ubi_wl_entry *get_peb_for_wl(struct ubi_device *ubi)
{
<------>struct ubi_fm_pool *pool = &ubi->fm_wl_pool;
<------>int pnum;
 
<------>ubi_assert(rwsem_is_locked(&ubi->fm_eba_sem));
 
<------>if (pool->used == pool->size) {
<------><------>/* We cannot update the fastmap here because this
<------><------> * function is called in atomic context.
<------><------> * Let's fail here and refill/update it as soon as possible. */
<------><------>if (!ubi->fm_work_scheduled) {
<------><------><------>ubi->fm_work_scheduled = 1;
<------><------><------>schedule_work(&ubi->fm_work);
<------><------>}
<------><------>return NULL;
<------>}
 
<------>pnum = pool->pebs[pool->used++];
<------>return ubi->lookuptbl[pnum];
}
 
/**
 * ubi_ensure_anchor_pebs - schedule wear-leveling to produce an anchor PEB.
 * @ubi: UBI device description object
 */
int ubi_ensure_anchor_pebs(struct ubi_device *ubi)
{
<------>struct ubi_work *wrk;
 
<------>spin_lock(&ubi->wl_lock);
 
<------>/* Do we have a next anchor? */
<------>if (!ubi->fm_next_anchor) {
<------><------>ubi->fm_next_anchor = ubi_wl_get_fm_peb(ubi, 1);
<------><------>if (!ubi->fm_next_anchor)
<------><------><------>/* Tell wear leveling to produce a new anchor PEB */
<------><------><------>ubi->fm_do_produce_anchor = 1;
<------>}
 
<------>/* Do wear leveling to get a new anchor PEB or check the
<------> * existing next anchor candidate.
<------> */
<------>if (ubi->wl_scheduled) {
<------><------>spin_unlock(&ubi->wl_lock);
<------><------>return 0;
<------>}
<------>ubi->wl_scheduled = 1;
<------>spin_unlock(&ubi->wl_lock);
 
<------>wrk = kmalloc(sizeof(struct ubi_work), GFP_NOFS);
<------>if (!wrk) {
<------><------>spin_lock(&ubi->wl_lock);
<------><------>ubi->wl_scheduled = 0;
<------><------>spin_unlock(&ubi->wl_lock);
<------><------>return -ENOMEM;
<------>}
 
<------>wrk->func = &wear_leveling_worker;
<------>__schedule_ubi_work(ubi, wrk);
<------>return 0;
}
 
/**
 * ubi_wl_put_fm_peb - returns a PEB used in a fastmap to the wear-leveling
 * sub-system.
 * see: ubi_wl_put_peb()
 *
 * @ubi: UBI device description object
 * @fm_e: physical eraseblock to return
 * @lnum: the last used logical eraseblock number for the PEB
 * @torture: if this physical eraseblock has to be tortured
 */
int ubi_wl_put_fm_peb(struct ubi_device *ubi, struct ubi_wl_entry *fm_e,
<------><------>      int lnum, int torture)
{
<------>struct ubi_wl_entry *e;
<------>int vol_id, pnum = fm_e->pnum;
 
<------>dbg_wl("PEB %d", pnum);
 
<------>ubi_assert(pnum >= 0);
<------>ubi_assert(pnum < ubi->peb_count);
 
<------>spin_lock(&ubi->wl_lock);
<------>e = ubi->lookuptbl[pnum];
 
<------>/* This can happen if we recovered from a fastmap the very
<------> * first time and writing now a new one. In this case the wl system
<------> * has never seen any PEB used by the original fastmap.
<------> */
<------>if (!e) {
<------><------>e = fm_e;
<------><------>ubi_assert(e->ec >= 0);
<------><------>ubi->lookuptbl[pnum] = e;
<------>}
 
<------>spin_unlock(&ubi->wl_lock);
 
<------>vol_id = lnum ? UBI_FM_DATA_VOLUME_ID : UBI_FM_SB_VOLUME_ID;
<------>return schedule_erase(ubi, e, vol_id, lnum, torture, true);
}
 
/**
 * ubi_is_erase_work - checks whether a work is erase work.
 * @wrk: The work object to be checked
 */
int ubi_is_erase_work(struct ubi_work *wrk)
{
<------>return wrk->func == erase_worker;
}
 
static void ubi_fastmap_close(struct ubi_device *ubi)
{
<------>int i;
 
<------>return_unused_pool_pebs(ubi, &ubi->fm_pool);
<------>return_unused_pool_pebs(ubi, &ubi->fm_wl_pool);
 
<------>if (ubi->fm_anchor) {
<------><------>return_unused_peb(ubi, ubi->fm_anchor);
<------><------>ubi->fm_anchor = NULL;
<------>}
 
<------>if (ubi->fm_next_anchor) {
<------><------>return_unused_peb(ubi, ubi->fm_next_anchor);
<------><------>ubi->fm_next_anchor = NULL;
<------>}
 
<------>if (ubi->fm) {
<------><------>for (i = 0; i < ubi->fm->used_blocks; i++)
<------><------><------>kfree(ubi->fm->e[i]);
<------>}
<------>kfree(ubi->fm);
}
 
/**
 * may_reserve_for_fm - tests whether a PEB shall be reserved for fastmap.
 * See find_mean_wl_entry()
 *
 * @ubi: UBI device description object
 * @e: physical eraseblock to return
 * @root: RB tree to test against.
 */
static struct ubi_wl_entry *may_reserve_for_fm(struct ubi_device *ubi,
<------><------><------><------><------>   struct ubi_wl_entry *e,
<------><------><------><------><------>   struct rb_root *root) {
<------>if (e && !ubi->fm_disabled && !ubi->fm &&
<------>    e->pnum < UBI_FM_MAX_START)
<------><------>e = rb_entry(rb_next(root->rb_node),
<------><------><------>     struct ubi_wl_entry, u.rb);
 
<------>return e;
}