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- /*
- * This file is part of UBIFS.
- *
- * Copyright (C) 2006-2008 Nokia Corporation.
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 as published by
- * the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
- * more details.
- *
- * You should have received a copy of the GNU General Public License along with
- * this program; if not, write to the Free Software Foundation, Inc., 51
- * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
- *
- * Authors: Adrian Hunter
- * Artem Bityutskiy (Битюцкий Артём)
- */
- /*
- * This file implements the functions that access LEB properties and their
- * categories. LEBs are categorized based on the needs of UBIFS, and the
- * categories are stored as either heaps or lists to provide a fast way of
- * finding a LEB in a particular category. For example, UBIFS may need to find
- * an empty LEB for the journal, or a very dirty LEB for garbage collection.
- */
- #include "ubifs.h"
- /**
- * get_heap_comp_val - get the LEB properties value for heap comparisons.
- * @lprops: LEB properties
- * @cat: LEB category
- */
- static int get_heap_comp_val(struct ubifs_lprops *lprops, int cat)
- {
- switch (cat) {
- case LPROPS_FREE:
- return lprops->free;
- case LPROPS_DIRTY_IDX:
- return lprops->free + lprops->dirty;
- default:
- return lprops->dirty;
- }
- }
- /**
- * move_up_lpt_heap - move a new heap entry up as far as possible.
- * @c: UBIFS file-system description object
- * @heap: LEB category heap
- * @lprops: LEB properties to move
- * @cat: LEB category
- *
- * New entries to a heap are added at the bottom and then moved up until the
- * parent's value is greater. In the case of LPT's category heaps, the value
- * is either the amount of free space or the amount of dirty space, depending
- * on the category.
- */
- static void move_up_lpt_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap,
- struct ubifs_lprops *lprops, int cat)
- {
- int val1, val2, hpos;
- hpos = lprops->hpos;
- if (!hpos)
- return; /* Already top of the heap */
- val1 = get_heap_comp_val(lprops, cat);
- /* Compare to parent and, if greater, move up the heap */
- do {
- int ppos = (hpos - 1) / 2;
- val2 = get_heap_comp_val(heap->arr[ppos], cat);
- if (val2 >= val1)
- return;
- /* Greater than parent so move up */
- heap->arr[ppos]->hpos = hpos;
- heap->arr[hpos] = heap->arr[ppos];
- heap->arr[ppos] = lprops;
- lprops->hpos = ppos;
- hpos = ppos;
- } while (hpos);
- }
- /**
- * adjust_lpt_heap - move a changed heap entry up or down the heap.
- * @c: UBIFS file-system description object
- * @heap: LEB category heap
- * @lprops: LEB properties to move
- * @hpos: heap position of @lprops
- * @cat: LEB category
- *
- * Changed entries in a heap are moved up or down until the parent's value is
- * greater. In the case of LPT's category heaps, the value is either the amount
- * of free space or the amount of dirty space, depending on the category.
- */
- static void adjust_lpt_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap,
- struct ubifs_lprops *lprops, int hpos, int cat)
- {
- int val1, val2, val3, cpos;
- val1 = get_heap_comp_val(lprops, cat);
- /* Compare to parent and, if greater than parent, move up the heap */
- if (hpos) {
- int ppos = (hpos - 1) / 2;
- val2 = get_heap_comp_val(heap->arr[ppos], cat);
- if (val1 > val2) {
- /* Greater than parent so move up */
- while (1) {
- heap->arr[ppos]->hpos = hpos;
- heap->arr[hpos] = heap->arr[ppos];
- heap->arr[ppos] = lprops;
- lprops->hpos = ppos;
- hpos = ppos;
- if (!hpos)
- return;
- ppos = (hpos - 1) / 2;
- val2 = get_heap_comp_val(heap->arr[ppos], cat);
- if (val1 <= val2)
- return;
- /* Still greater than parent so keep going */
- }
- }
- }
- /* Not greater than parent, so compare to children */
- while (1) {
- /* Compare to left child */
- cpos = hpos * 2 + 1;
- if (cpos >= heap->cnt)
- return;
- val2 = get_heap_comp_val(heap->arr[cpos], cat);
- if (val1 < val2) {
- /* Less than left child, so promote biggest child */
- if (cpos + 1 < heap->cnt) {
- val3 = get_heap_comp_val(heap->arr[cpos + 1],
- cat);
- if (val3 > val2)
- cpos += 1; /* Right child is bigger */
- }
- heap->arr[cpos]->hpos = hpos;
- heap->arr[hpos] = heap->arr[cpos];
- heap->arr[cpos] = lprops;
- lprops->hpos = cpos;
- hpos = cpos;
- continue;
- }
- /* Compare to right child */
- cpos += 1;
- if (cpos >= heap->cnt)
- return;
- val3 = get_heap_comp_val(heap->arr[cpos], cat);
- if (val1 < val3) {
- /* Less than right child, so promote right child */
- heap->arr[cpos]->hpos = hpos;
- heap->arr[hpos] = heap->arr[cpos];
- heap->arr[cpos] = lprops;
- lprops->hpos = cpos;
- hpos = cpos;
- continue;
- }
- return;
- }
- }
- /**
- * add_to_lpt_heap - add LEB properties to a LEB category heap.
- * @c: UBIFS file-system description object
- * @lprops: LEB properties to add
- * @cat: LEB category
- *
- * This function returns %1 if @lprops is added to the heap for LEB category
- * @cat, otherwise %0 is returned because the heap is full.
- */
- static int add_to_lpt_heap(struct ubifs_info *c, struct ubifs_lprops *lprops,
- int cat)
- {
- struct ubifs_lpt_heap *heap = &c->lpt_heap[cat - 1];
- if (heap->cnt >= heap->max_cnt) {
- const int b = LPT_HEAP_SZ / 2 - 1;
- int cpos, val1, val2;
- /* Compare to some other LEB on the bottom of heap */
- /* Pick a position kind of randomly */
- cpos = (((size_t)lprops >> 4) & b) + b;
- ubifs_assert(cpos >= b);
- ubifs_assert(cpos < LPT_HEAP_SZ);
- ubifs_assert(cpos < heap->cnt);
- val1 = get_heap_comp_val(lprops, cat);
- val2 = get_heap_comp_val(heap->arr[cpos], cat);
- if (val1 > val2) {
- struct ubifs_lprops *lp;
- lp = heap->arr[cpos];
- lp->flags &= ~LPROPS_CAT_MASK;
- lp->flags |= LPROPS_UNCAT;
- list_add(&lp->list, &c->uncat_list);
- lprops->hpos = cpos;
- heap->arr[cpos] = lprops;
- move_up_lpt_heap(c, heap, lprops, cat);
- dbg_check_heap(c, heap, cat, lprops->hpos);
- return 1; /* Added to heap */
- }
- dbg_check_heap(c, heap, cat, -1);
- return 0; /* Not added to heap */
- } else {
- lprops->hpos = heap->cnt++;
- heap->arr[lprops->hpos] = lprops;
- move_up_lpt_heap(c, heap, lprops, cat);
- dbg_check_heap(c, heap, cat, lprops->hpos);
- return 1; /* Added to heap */
- }
- }
- /**
- * remove_from_lpt_heap - remove LEB properties from a LEB category heap.
- * @c: UBIFS file-system description object
- * @lprops: LEB properties to remove
- * @cat: LEB category
- */
- static void remove_from_lpt_heap(struct ubifs_info *c,
- struct ubifs_lprops *lprops, int cat)
- {
- struct ubifs_lpt_heap *heap;
- int hpos = lprops->hpos;
- heap = &c->lpt_heap[cat - 1];
- ubifs_assert(hpos >= 0 && hpos < heap->cnt);
- ubifs_assert(heap->arr[hpos] == lprops);
- heap->cnt -= 1;
- if (hpos < heap->cnt) {
- heap->arr[hpos] = heap->arr[heap->cnt];
- heap->arr[hpos]->hpos = hpos;
- adjust_lpt_heap(c, heap, heap->arr[hpos], hpos, cat);
- }
- dbg_check_heap(c, heap, cat, -1);
- }
- /**
- * lpt_heap_replace - replace lprops in a category heap.
- * @c: UBIFS file-system description object
- * @old_lprops: LEB properties to replace
- * @new_lprops: LEB properties with which to replace
- * @cat: LEB category
- *
- * During commit it is sometimes necessary to copy a pnode (see dirty_cow_pnode)
- * and the lprops that the pnode contains. When that happens, references in
- * the category heaps to those lprops must be updated to point to the new
- * lprops. This function does that.
- */
- static void lpt_heap_replace(struct ubifs_info *c,
- struct ubifs_lprops *old_lprops,
- struct ubifs_lprops *new_lprops, int cat)
- {
- struct ubifs_lpt_heap *heap;
- int hpos = new_lprops->hpos;
- heap = &c->lpt_heap[cat - 1];
- heap->arr[hpos] = new_lprops;
- }
- /**
- * ubifs_add_to_cat - add LEB properties to a category list or heap.
- * @c: UBIFS file-system description object
- * @lprops: LEB properties to add
- * @cat: LEB category to which to add
- *
- * LEB properties are categorized to enable fast find operations.
- */
- void ubifs_add_to_cat(struct ubifs_info *c, struct ubifs_lprops *lprops,
- int cat)
- {
- switch (cat) {
- case LPROPS_DIRTY:
- case LPROPS_DIRTY_IDX:
- case LPROPS_FREE:
- if (add_to_lpt_heap(c, lprops, cat))
- break;
- /* No more room on heap so make it uncategorized */
- cat = LPROPS_UNCAT;
- /* Fall through */
- case LPROPS_UNCAT:
- list_add(&lprops->list, &c->uncat_list);
- break;
- case LPROPS_EMPTY:
- list_add(&lprops->list, &c->empty_list);
- break;
- case LPROPS_FREEABLE:
- list_add(&lprops->list, &c->freeable_list);
- c->freeable_cnt += 1;
- break;
- case LPROPS_FRDI_IDX:
- list_add(&lprops->list, &c->frdi_idx_list);
- break;
- default:
- ubifs_assert(0);
- }
- lprops->flags &= ~LPROPS_CAT_MASK;
- lprops->flags |= cat;
- }
- /**
- * ubifs_remove_from_cat - remove LEB properties from a category list or heap.
- * @c: UBIFS file-system description object
- * @lprops: LEB properties to remove
- * @cat: LEB category from which to remove
- *
- * LEB properties are categorized to enable fast find operations.
- */
- static void ubifs_remove_from_cat(struct ubifs_info *c,
- struct ubifs_lprops *lprops, int cat)
- {
- switch (cat) {
- case LPROPS_DIRTY:
- case LPROPS_DIRTY_IDX:
- case LPROPS_FREE:
- remove_from_lpt_heap(c, lprops, cat);
- break;
- case LPROPS_FREEABLE:
- c->freeable_cnt -= 1;
- ubifs_assert(c->freeable_cnt >= 0);
- /* Fall through */
- case LPROPS_UNCAT:
- case LPROPS_EMPTY:
- case LPROPS_FRDI_IDX:
- ubifs_assert(!list_empty(&lprops->list));
- list_del(&lprops->list);
- break;
- default:
- ubifs_assert(0);
- }
- }
- /**
- * ubifs_replace_cat - replace lprops in a category list or heap.
- * @c: UBIFS file-system description object
- * @old_lprops: LEB properties to replace
- * @new_lprops: LEB properties with which to replace
- *
- * During commit it is sometimes necessary to copy a pnode (see dirty_cow_pnode)
- * and the lprops that the pnode contains. When that happens, references in
- * category lists and heaps must be replaced. This function does that.
- */
- void ubifs_replace_cat(struct ubifs_info *c, struct ubifs_lprops *old_lprops,
- struct ubifs_lprops *new_lprops)
- {
- int cat;
- cat = new_lprops->flags & LPROPS_CAT_MASK;
- switch (cat) {
- case LPROPS_DIRTY:
- case LPROPS_DIRTY_IDX:
- case LPROPS_FREE:
- lpt_heap_replace(c, old_lprops, new_lprops, cat);
- break;
- case LPROPS_UNCAT:
- case LPROPS_EMPTY:
- case LPROPS_FREEABLE:
- case LPROPS_FRDI_IDX:
- list_replace(&old_lprops->list, &new_lprops->list);
- break;
- default:
- ubifs_assert(0);
- }
- }
- /**
- * ubifs_ensure_cat - ensure LEB properties are categorized.
- * @c: UBIFS file-system description object
- * @lprops: LEB properties
- *
- * A LEB may have fallen off of the bottom of a heap, and ended up as
- * uncategorized even though it has enough space for us now. If that is the case
- * this function will put the LEB back onto a heap.
- */
- void ubifs_ensure_cat(struct ubifs_info *c, struct ubifs_lprops *lprops)
- {
- int cat = lprops->flags & LPROPS_CAT_MASK;
- if (cat != LPROPS_UNCAT)
- return;
- cat = ubifs_categorize_lprops(c, lprops);
- if (cat == LPROPS_UNCAT)
- return;
- ubifs_remove_from_cat(c, lprops, LPROPS_UNCAT);
- ubifs_add_to_cat(c, lprops, cat);
- }
- /**
- * ubifs_categorize_lprops - categorize LEB properties.
- * @c: UBIFS file-system description object
- * @lprops: LEB properties to categorize
- *
- * LEB properties are categorized to enable fast find operations. This function
- * returns the LEB category to which the LEB properties belong. Note however
- * that if the LEB category is stored as a heap and the heap is full, the
- * LEB properties may have their category changed to %LPROPS_UNCAT.
- */
- int ubifs_categorize_lprops(const struct ubifs_info *c,
- const struct ubifs_lprops *lprops)
- {
- if (lprops->flags & LPROPS_TAKEN)
- return LPROPS_UNCAT;
- if (lprops->free == c->leb_size) {
- ubifs_assert(!(lprops->flags & LPROPS_INDEX));
- return LPROPS_EMPTY;
- }
- if (lprops->free + lprops->dirty == c->leb_size) {
- if (lprops->flags & LPROPS_INDEX)
- return LPROPS_FRDI_IDX;
- else
- return LPROPS_FREEABLE;
- }
- if (lprops->flags & LPROPS_INDEX) {
- if (lprops->dirty + lprops->free >= c->min_idx_node_sz)
- return LPROPS_DIRTY_IDX;
- } else {
- if (lprops->dirty >= c->dead_wm &&
- lprops->dirty > lprops->free)
- return LPROPS_DIRTY;
- if (lprops->free > 0)
- return LPROPS_FREE;
- }
- return LPROPS_UNCAT;
- }
- /**
- * change_category - change LEB properties category.
- * @c: UBIFS file-system description object
- * @lprops: LEB properties to recategorize
- *
- * LEB properties are categorized to enable fast find operations. When the LEB
- * properties change they must be recategorized.
- */
- static void change_category(struct ubifs_info *c, struct ubifs_lprops *lprops)
- {
- int old_cat = lprops->flags & LPROPS_CAT_MASK;
- int new_cat = ubifs_categorize_lprops(c, lprops);
- if (old_cat == new_cat) {
- struct ubifs_lpt_heap *heap = &c->lpt_heap[new_cat - 1];
- /* lprops on a heap now must be moved up or down */
- if (new_cat < 1 || new_cat > LPROPS_HEAP_CNT)
- return; /* Not on a heap */
- heap = &c->lpt_heap[new_cat - 1];
- adjust_lpt_heap(c, heap, lprops, lprops->hpos, new_cat);
- } else {
- ubifs_remove_from_cat(c, lprops, old_cat);
- ubifs_add_to_cat(c, lprops, new_cat);
- }
- }
- /**
- * calc_dark - calculate LEB dark space size.
- * @c: the UBIFS file-system description object
- * @spc: amount of free and dirty space in the LEB
- *
- * This function calculates amount of dark space in an LEB which has @spc bytes
- * of free and dirty space. Returns the calculations result.
- *
- * Dark space is the space which is not always usable - it depends on which
- * nodes are written in which order. E.g., if an LEB has only 512 free bytes,
- * it is dark space, because it cannot fit a large data node. So UBIFS cannot
- * count on this LEB and treat these 512 bytes as usable because it is not true
- * if, for example, only big chunks of uncompressible data will be written to
- * the FS.
- */
- static int calc_dark(struct ubifs_info *c, int spc)
- {
- ubifs_assert(!(spc & 7));
- if (spc < c->dark_wm)
- return spc;
- /*
- * If we have slightly more space then the dark space watermark, we can
- * anyway safely assume it we'll be able to write a node of the
- * smallest size there.
- */
- if (spc - c->dark_wm < MIN_WRITE_SZ)
- return spc - MIN_WRITE_SZ;
- return c->dark_wm;
- }
- /**
- * is_lprops_dirty - determine if LEB properties are dirty.
- * @c: the UBIFS file-system description object
- * @lprops: LEB properties to test
- */
- static int is_lprops_dirty(struct ubifs_info *c, struct ubifs_lprops *lprops)
- {
- struct ubifs_pnode *pnode;
- int pos;
- pos = (lprops->lnum - c->main_first) & (UBIFS_LPT_FANOUT - 1);
- pnode = (struct ubifs_pnode *)container_of(lprops - pos,
- struct ubifs_pnode,
- lprops[0]);
- return !test_bit(COW_ZNODE, &pnode->flags) &&
- test_bit(DIRTY_CNODE, &pnode->flags);
- }
- /**
- * ubifs_change_lp - change LEB properties.
- * @c: the UBIFS file-system description object
- * @lp: LEB properties to change
- * @free: new free space amount
- * @dirty: new dirty space amount
- * @flags: new flags
- * @idx_gc_cnt: change to the count of idx_gc list
- *
- * This function changes LEB properties (@free, @dirty or @flag). However, the
- * property which has the %LPROPS_NC value is not changed. Returns a pointer to
- * the updated LEB properties on success and a negative error code on failure.
- *
- * Note, the LEB properties may have had to be copied (due to COW) and
- * consequently the pointer returned may not be the same as the pointer
- * passed.
- */
- const struct ubifs_lprops *ubifs_change_lp(struct ubifs_info *c,
- const struct ubifs_lprops *lp,
- int free, int dirty, int flags,
- int idx_gc_cnt)
- {
- /*
- * This is the only function that is allowed to change lprops, so we
- * discard the const qualifier.
- */
- struct ubifs_lprops *lprops = (struct ubifs_lprops *)lp;
- dbg_lp("LEB %d, free %d, dirty %d, flags %d",
- lprops->lnum, free, dirty, flags);
- ubifs_assert(mutex_is_locked(&c->lp_mutex));
- ubifs_assert(c->lst.empty_lebs >= 0 &&
- c->lst.empty_lebs <= c->main_lebs);
- ubifs_assert(c->freeable_cnt >= 0);
- ubifs_assert(c->freeable_cnt <= c->main_lebs);
- ubifs_assert(c->lst.taken_empty_lebs >= 0);
- ubifs_assert(c->lst.taken_empty_lebs <= c->lst.empty_lebs);
- ubifs_assert(!(c->lst.total_free & 7) && !(c->lst.total_dirty & 7));
- ubifs_assert(!(c->lst.total_dead & 7) && !(c->lst.total_dark & 7));
- ubifs_assert(!(c->lst.total_used & 7));
- ubifs_assert(free == LPROPS_NC || free >= 0);
- ubifs_assert(dirty == LPROPS_NC || dirty >= 0);
- if (!is_lprops_dirty(c, lprops)) {
- lprops = ubifs_lpt_lookup_dirty(c, lprops->lnum);
- if (IS_ERR(lprops))
- return lprops;
- } else
- ubifs_assert(lprops == ubifs_lpt_lookup_dirty(c, lprops->lnum));
- ubifs_assert(!(lprops->free & 7) && !(lprops->dirty & 7));
- spin_lock(&c->space_lock);
- if ((lprops->flags & LPROPS_TAKEN) && lprops->free == c->leb_size)
- c->lst.taken_empty_lebs -= 1;
- if (!(lprops->flags & LPROPS_INDEX)) {
- int old_spc;
- old_spc = lprops->free + lprops->dirty;
- if (old_spc < c->dead_wm)
- c->lst.total_dead -= old_spc;
- else
- c->lst.total_dark -= calc_dark(c, old_spc);
- c->lst.total_used -= c->leb_size - old_spc;
- }
- if (free != LPROPS_NC) {
- free = ALIGN(free, 8);
- c->lst.total_free += free - lprops->free;
- /* Increase or decrease empty LEBs counter if needed */
- if (free == c->leb_size) {
- if (lprops->free != c->leb_size)
- c->lst.empty_lebs += 1;
- } else if (lprops->free == c->leb_size)
- c->lst.empty_lebs -= 1;
- lprops->free = free;
- }
- if (dirty != LPROPS_NC) {
- dirty = ALIGN(dirty, 8);
- c->lst.total_dirty += dirty - lprops->dirty;
- lprops->dirty = dirty;
- }
- if (flags != LPROPS_NC) {
- /* Take care about indexing LEBs counter if needed */
- if ((lprops->flags & LPROPS_INDEX)) {
- if (!(flags & LPROPS_INDEX))
- c->lst.idx_lebs -= 1;
- } else if (flags & LPROPS_INDEX)
- c->lst.idx_lebs += 1;
- lprops->flags = flags;
- }
- if (!(lprops->flags & LPROPS_INDEX)) {
- int new_spc;
- new_spc = lprops->free + lprops->dirty;
- if (new_spc < c->dead_wm)
- c->lst.total_dead += new_spc;
- else
- c->lst.total_dark += calc_dark(c, new_spc);
- c->lst.total_used += c->leb_size - new_spc;
- }
- if ((lprops->flags & LPROPS_TAKEN) && lprops->free == c->leb_size)
- c->lst.taken_empty_lebs += 1;
- change_category(c, lprops);
- c->idx_gc_cnt += idx_gc_cnt;
- spin_unlock(&c->space_lock);
- return lprops;
- }
- /**
- * ubifs_get_lp_stats - get lprops statistics.
- * @c: UBIFS file-system description object
- * @st: return statistics
- */
- void ubifs_get_lp_stats(struct ubifs_info *c, struct ubifs_lp_stats *lst)
- {
- spin_lock(&c->space_lock);
- memcpy(lst, &c->lst, sizeof(struct ubifs_lp_stats));
- spin_unlock(&c->space_lock);
- }
- /**
- * ubifs_change_one_lp - change LEB properties.
- * @c: the UBIFS file-system description object
- * @lnum: LEB to change properties for
- * @free: amount of free space
- * @dirty: amount of dirty space
- * @flags_set: flags to set
- * @flags_clean: flags to clean
- * @idx_gc_cnt: change to the count of idx_gc list
- *
- * This function changes properties of LEB @lnum. It is a helper wrapper over
- * 'ubifs_change_lp()' which hides lprops get/release. The arguments are the
- * same as in case of 'ubifs_change_lp()'. Returns zero in case of success and
- * a negative error code in case of failure.
- */
- int ubifs_change_one_lp(struct ubifs_info *c, int lnum, int free, int dirty,
- int flags_set, int flags_clean, int idx_gc_cnt)
- {
- int err = 0, flags;
- const struct ubifs_lprops *lp;
- ubifs_get_lprops(c);
- lp = ubifs_lpt_lookup_dirty(c, lnum);
- if (IS_ERR(lp)) {
- err = PTR_ERR(lp);
- goto out;
- }
- flags = (lp->flags | flags_set) & ~flags_clean;
- lp = ubifs_change_lp(c, lp, free, dirty, flags, idx_gc_cnt);
- if (IS_ERR(lp))
- err = PTR_ERR(lp);
- out:
- ubifs_release_lprops(c);
- return err;
- }
- /**
- * ubifs_update_one_lp - update LEB properties.
- * @c: the UBIFS file-system description object
- * @lnum: LEB to change properties for
- * @free: amount of free space
- * @dirty: amount of dirty space to add
- * @flags_set: flags to set
- * @flags_clean: flags to clean
- *
- * This function is the same as 'ubifs_change_one_lp()' but @dirty is added to
- * current dirty space, not substitutes it.
- */
- int ubifs_update_one_lp(struct ubifs_info *c, int lnum, int free, int dirty,
- int flags_set, int flags_clean)
- {
- int err = 0, flags;
- const struct ubifs_lprops *lp;
- ubifs_get_lprops(c);
- lp = ubifs_lpt_lookup_dirty(c, lnum);
- if (IS_ERR(lp)) {
- err = PTR_ERR(lp);
- goto out;
- }
- flags = (lp->flags | flags_set) & ~flags_clean;
- lp = ubifs_change_lp(c, lp, free, lp->dirty + dirty, flags, 0);
- if (IS_ERR(lp))
- err = PTR_ERR(lp);
- out:
- ubifs_release_lprops(c);
- return err;
- }
- /**
- * ubifs_read_one_lp - read LEB properties.
- * @c: the UBIFS file-system description object
- * @lnum: LEB to read properties for
- * @lp: where to store read properties
- *
- * This helper function reads properties of a LEB @lnum and stores them in @lp.
- * Returns zero in case of success and a negative error code in case of
- * failure.
- */
- int ubifs_read_one_lp(struct ubifs_info *c, int lnum, struct ubifs_lprops *lp)
- {
- int err = 0;
- const struct ubifs_lprops *lpp;
- ubifs_get_lprops(c);
- lpp = ubifs_lpt_lookup(c, lnum);
- if (IS_ERR(lpp)) {
- err = PTR_ERR(lpp);
- goto out;
- }
- memcpy(lp, lpp, sizeof(struct ubifs_lprops));
- out:
- ubifs_release_lprops(c);
- return err;
- }
- /**
- * ubifs_fast_find_free - try to find a LEB with free space quickly.
- * @c: the UBIFS file-system description object
- *
- * This function returns LEB properties for a LEB with free space or %NULL if
- * the function is unable to find a LEB quickly.
- */
- const struct ubifs_lprops *ubifs_fast_find_free(struct ubifs_info *c)
- {
- struct ubifs_lprops *lprops;
- struct ubifs_lpt_heap *heap;
- ubifs_assert(mutex_is_locked(&c->lp_mutex));
- heap = &c->lpt_heap[LPROPS_FREE - 1];
- if (heap->cnt == 0)
- return NULL;
- lprops = heap->arr[0];
- ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
- ubifs_assert(!(lprops->flags & LPROPS_INDEX));
- return lprops;
- }
- /**
- * ubifs_fast_find_empty - try to find an empty LEB quickly.
- * @c: the UBIFS file-system description object
- *
- * This function returns LEB properties for an empty LEB or %NULL if the
- * function is unable to find an empty LEB quickly.
- */
- const struct ubifs_lprops *ubifs_fast_find_empty(struct ubifs_info *c)
- {
- struct ubifs_lprops *lprops;
- ubifs_assert(mutex_is_locked(&c->lp_mutex));
- if (list_empty(&c->empty_list))
- return NULL;
- lprops = list_entry(c->empty_list.next, struct ubifs_lprops, list);
- ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
- ubifs_assert(!(lprops->flags & LPROPS_INDEX));
- ubifs_assert(lprops->free == c->leb_size);
- return lprops;
- }
- /**
- * ubifs_fast_find_freeable - try to find a freeable LEB quickly.
- * @c: the UBIFS file-system description object
- *
- * This function returns LEB properties for a freeable LEB or %NULL if the
- * function is unable to find a freeable LEB quickly.
- */
- const struct ubifs_lprops *ubifs_fast_find_freeable(struct ubifs_info *c)
- {
- struct ubifs_lprops *lprops;
- ubifs_assert(mutex_is_locked(&c->lp_mutex));
- if (list_empty(&c->freeable_list))
- return NULL;
- lprops = list_entry(c->freeable_list.next, struct ubifs_lprops, list);
- ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
- ubifs_assert(!(lprops->flags & LPROPS_INDEX));
- ubifs_assert(lprops->free + lprops->dirty == c->leb_size);
- ubifs_assert(c->freeable_cnt > 0);
- return lprops;
- }
- /**
- * ubifs_fast_find_frdi_idx - try to find a freeable index LEB quickly.
- * @c: the UBIFS file-system description object
- *
- * This function returns LEB properties for a freeable index LEB or %NULL if the
- * function is unable to find a freeable index LEB quickly.
- */
- const struct ubifs_lprops *ubifs_fast_find_frdi_idx(struct ubifs_info *c)
- {
- struct ubifs_lprops *lprops;
- ubifs_assert(mutex_is_locked(&c->lp_mutex));
- if (list_empty(&c->frdi_idx_list))
- return NULL;
- lprops = list_entry(c->frdi_idx_list.next, struct ubifs_lprops, list);
- ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
- ubifs_assert((lprops->flags & LPROPS_INDEX));
- ubifs_assert(lprops->free + lprops->dirty == c->leb_size);
- return lprops;
- }
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