+++ /dev/null
-/*
- * 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 TNC functions for committing */
-
-#include "ubifs.h"
-
-/**
- * make_idx_node - make an index node for fill-the-gaps method of TNC commit.
- * @c: UBIFS file-system description object
- * @idx: buffer in which to place new index node
- * @znode: znode from which to make new index node
- * @lnum: LEB number where new index node will be written
- * @offs: offset where new index node will be written
- * @len: length of new index node
- */
-static int make_idx_node(struct ubifs_info *c, struct ubifs_idx_node *idx,
- struct ubifs_znode *znode, int lnum, int offs, int len)
-{
- struct ubifs_znode *zp;
- int i, err;
-
- /* Make index node */
- idx->ch.node_type = UBIFS_IDX_NODE;
- idx->child_cnt = cpu_to_le16(znode->child_cnt);
- idx->level = cpu_to_le16(znode->level);
- for (i = 0; i < znode->child_cnt; i++) {
- struct ubifs_branch *br = ubifs_idx_branch(c, idx, i);
- struct ubifs_zbranch *zbr = &znode->zbranch[i];
-
- key_write_idx(c, &zbr->key, &br->key);
- br->lnum = cpu_to_le32(zbr->lnum);
- br->offs = cpu_to_le32(zbr->offs);
- br->len = cpu_to_le32(zbr->len);
- if (!zbr->lnum || !zbr->len) {
- ubifs_err("bad ref in znode");
- dbg_dump_znode(c, znode);
- if (zbr->znode)
- dbg_dump_znode(c, zbr->znode);
- }
- }
- ubifs_prepare_node(c, idx, len, 0);
-
-#ifdef CONFIG_UBIFS_FS_DEBUG
- znode->lnum = lnum;
- znode->offs = offs;
- znode->len = len;
-#endif
-
- err = insert_old_idx_znode(c, znode);
-
- /* Update the parent */
- zp = znode->parent;
- if (zp) {
- struct ubifs_zbranch *zbr;
-
- zbr = &zp->zbranch[znode->iip];
- zbr->lnum = lnum;
- zbr->offs = offs;
- zbr->len = len;
- } else {
- c->zroot.lnum = lnum;
- c->zroot.offs = offs;
- c->zroot.len = len;
- }
- c->calc_idx_sz += ALIGN(len, 8);
-
- atomic_long_dec(&c->dirty_zn_cnt);
-
- ubifs_assert(ubifs_zn_dirty(znode));
- ubifs_assert(test_bit(COW_ZNODE, &znode->flags));
-
- __clear_bit(DIRTY_ZNODE, &znode->flags);
- __clear_bit(COW_ZNODE, &znode->flags);
-
- return err;
-}
-
-/**
- * fill_gap - make index nodes in gaps in dirty index LEBs.
- * @c: UBIFS file-system description object
- * @lnum: LEB number that gap appears in
- * @gap_start: offset of start of gap
- * @gap_end: offset of end of gap
- * @dirt: adds dirty space to this
- *
- * This function returns the number of index nodes written into the gap.
- */
-static int fill_gap(struct ubifs_info *c, int lnum, int gap_start, int gap_end,
- int *dirt)
-{
- int len, gap_remains, gap_pos, written, pad_len;
-
- ubifs_assert((gap_start & 7) == 0);
- ubifs_assert((gap_end & 7) == 0);
- ubifs_assert(gap_end >= gap_start);
-
- gap_remains = gap_end - gap_start;
- if (!gap_remains)
- return 0;
- gap_pos = gap_start;
- written = 0;
- while (c->enext) {
- len = ubifs_idx_node_sz(c, c->enext->child_cnt);
- if (len < gap_remains) {
- struct ubifs_znode *znode = c->enext;
- const int alen = ALIGN(len, 8);
- int err;
-
- ubifs_assert(alen <= gap_remains);
- err = make_idx_node(c, c->ileb_buf + gap_pos, znode,
- lnum, gap_pos, len);
- if (err)
- return err;
- gap_remains -= alen;
- gap_pos += alen;
- c->enext = znode->cnext;
- if (c->enext == c->cnext)
- c->enext = NULL;
- written += 1;
- } else
- break;
- }
- if (gap_end == c->leb_size) {
- c->ileb_len = ALIGN(gap_pos, c->min_io_size);
- /* Pad to end of min_io_size */
- pad_len = c->ileb_len - gap_pos;
- } else
- /* Pad to end of gap */
- pad_len = gap_remains;
- dbg_gc("LEB %d:%d to %d len %d nodes written %d wasted bytes %d",
- lnum, gap_start, gap_end, gap_end - gap_start, written, pad_len);
- ubifs_pad(c, c->ileb_buf + gap_pos, pad_len);
- *dirt += pad_len;
- return written;
-}
-
-/**
- * find_old_idx - find an index node obsoleted since the last commit start.
- * @c: UBIFS file-system description object
- * @lnum: LEB number of obsoleted index node
- * @offs: offset of obsoleted index node
- *
- * Returns %1 if found and %0 otherwise.
- */
-static int find_old_idx(struct ubifs_info *c, int lnum, int offs)
-{
- struct ubifs_old_idx *o;
- struct rb_node *p;
-
- p = c->old_idx.rb_node;
- while (p) {
- o = rb_entry(p, struct ubifs_old_idx, rb);
- if (lnum < o->lnum)
- p = p->rb_left;
- else if (lnum > o->lnum)
- p = p->rb_right;
- else if (offs < o->offs)
- p = p->rb_left;
- else if (offs > o->offs)
- p = p->rb_right;
- else
- return 1;
- }
- return 0;
-}
-
-/**
- * is_idx_node_in_use - determine if an index node can be overwritten.
- * @c: UBIFS file-system description object
- * @key: key of index node
- * @level: index node level
- * @lnum: LEB number of index node
- * @offs: offset of index node
- *
- * If @key / @lnum / @offs identify an index node that was not part of the old
- * index, then this function returns %0 (obsolete). Else if the index node was
- * part of the old index but is now dirty %1 is returned, else if it is clean %2
- * is returned. A negative error code is returned on failure.
- */
-static int is_idx_node_in_use(struct ubifs_info *c, union ubifs_key *key,
- int level, int lnum, int offs)
-{
- int ret;
-
- ret = is_idx_node_in_tnc(c, key, level, lnum, offs);
- if (ret < 0)
- return ret; /* Error code */
- if (ret == 0)
- if (find_old_idx(c, lnum, offs))
- return 1;
- return ret;
-}
-
-/**
- * layout_leb_in_gaps - layout index nodes using in-the-gaps method.
- * @c: UBIFS file-system description object
- * @p: return LEB number here
- *
- * This function lays out new index nodes for dirty znodes using in-the-gaps
- * method of TNC commit.
- * This function merely puts the next znode into the next gap, making no attempt
- * to try to maximise the number of znodes that fit.
- * This function returns the number of index nodes written into the gaps, or a
- * negative error code on failure.
- */
-static int layout_leb_in_gaps(struct ubifs_info *c, int *p)
-{
- struct ubifs_scan_leb *sleb;
- struct ubifs_scan_node *snod;
- int lnum, dirt = 0, gap_start, gap_end, err, written, tot_written;
-
- tot_written = 0;
- /* Get an index LEB with lots of obsolete index nodes */
- lnum = ubifs_find_dirty_idx_leb(c);
- if (lnum < 0)
- /*
- * There also may be dirt in the index head that could be
- * filled, however we do not check there at present.
- */
- return lnum; /* Error code */
- *p = lnum;
- dbg_gc("LEB %d", lnum);
- /*
- * Scan the index LEB. We use the generic scan for this even though
- * it is more comprehensive and less efficient than is needed for this
- * purpose.
- */
- sleb = ubifs_scan(c, lnum, 0, c->ileb_buf);
- c->ileb_len = 0;
- if (IS_ERR(sleb))
- return PTR_ERR(sleb);
- gap_start = 0;
- list_for_each_entry(snod, &sleb->nodes, list) {
- struct ubifs_idx_node *idx;
- int in_use, level;
-
- ubifs_assert(snod->type == UBIFS_IDX_NODE);
- idx = snod->node;
- key_read(c, ubifs_idx_key(c, idx), &snod->key);
- level = le16_to_cpu(idx->level);
- /* Determine if the index node is in use (not obsolete) */
- in_use = is_idx_node_in_use(c, &snod->key, level, lnum,
- snod->offs);
- if (in_use < 0) {
- ubifs_scan_destroy(sleb);
- return in_use; /* Error code */
- }
- if (in_use) {
- if (in_use == 1)
- dirt += ALIGN(snod->len, 8);
- /*
- * The obsolete index nodes form gaps that can be
- * overwritten. This gap has ended because we have
- * found an index node that is still in use
- * i.e. not obsolete
- */
- gap_end = snod->offs;
- /* Try to fill gap */
- written = fill_gap(c, lnum, gap_start, gap_end, &dirt);
- if (written < 0) {
- ubifs_scan_destroy(sleb);
- return written; /* Error code */
- }
- tot_written += written;
- gap_start = ALIGN(snod->offs + snod->len, 8);
- }
- }
- ubifs_scan_destroy(sleb);
- c->ileb_len = c->leb_size;
- gap_end = c->leb_size;
- /* Try to fill gap */
- written = fill_gap(c, lnum, gap_start, gap_end, &dirt);
- if (written < 0)
- return written; /* Error code */
- tot_written += written;
- if (tot_written == 0) {
- struct ubifs_lprops lp;
-
- dbg_gc("LEB %d wrote %d index nodes", lnum, tot_written);
- err = ubifs_read_one_lp(c, lnum, &lp);
- if (err)
- return err;
- if (lp.free == c->leb_size) {
- /*
- * We must have snatched this LEB from the idx_gc list
- * so we need to correct the free and dirty space.
- */
- err = ubifs_change_one_lp(c, lnum,
- c->leb_size - c->ileb_len,
- dirt, 0, 0, 0);
- if (err)
- return err;
- }
- return 0;
- }
- err = ubifs_change_one_lp(c, lnum, c->leb_size - c->ileb_len, dirt,
- 0, 0, 0);
- if (err)
- return err;
- err = ubifs_leb_change(c, lnum, c->ileb_buf, c->ileb_len,
- UBI_SHORTTERM);
- if (err)
- return err;
- dbg_gc("LEB %d wrote %d index nodes", lnum, tot_written);
- return tot_written;
-}
-
-/**
- * get_leb_cnt - calculate the number of empty LEBs needed to commit.
- * @c: UBIFS file-system description object
- * @cnt: number of znodes to commit
- *
- * This function returns the number of empty LEBs needed to commit @cnt znodes
- * to the current index head. The number is not exact and may be more than
- * needed.
- */
-static int get_leb_cnt(struct ubifs_info *c, int cnt)
-{
- int d;
-
- /* Assume maximum index node size (i.e. overestimate space needed) */
- cnt -= (c->leb_size - c->ihead_offs) / c->max_idx_node_sz;
- if (cnt < 0)
- cnt = 0;
- d = c->leb_size / c->max_idx_node_sz;
- return DIV_ROUND_UP(cnt, d);
-}
-
-/**
- * layout_in_gaps - in-the-gaps method of committing TNC.
- * @c: UBIFS file-system description object
- * @cnt: number of dirty znodes to commit.
- *
- * This function lays out new index nodes for dirty znodes using in-the-gaps
- * method of TNC commit.
- *
- * This function returns %0 on success and a negative error code on failure.
- */
-static int layout_in_gaps(struct ubifs_info *c, int cnt)
-{
- int err, leb_needed_cnt, written, *p;
-
- dbg_gc("%d znodes to write", cnt);
-
- c->gap_lebs = kmalloc(sizeof(int) * (c->lst.idx_lebs + 1), GFP_NOFS);
- if (!c->gap_lebs)
- return -ENOMEM;
-
- p = c->gap_lebs;
- do {
- ubifs_assert(p < c->gap_lebs + sizeof(int) * c->lst.idx_lebs);
- written = layout_leb_in_gaps(c, p);
- if (written < 0) {
- err = written;
- if (err != -ENOSPC) {
- kfree(c->gap_lebs);
- c->gap_lebs = NULL;
- return err;
- }
- if (!dbg_force_in_the_gaps_enabled) {
- /*
- * Do not print scary warnings if the debugging
- * option which forces in-the-gaps is enabled.
- */
- ubifs_err("out of space");
- spin_lock(&c->space_lock);
- dbg_dump_budg(c);
- spin_unlock(&c->space_lock);
- dbg_dump_lprops(c);
- }
- /* Try to commit anyway */
- err = 0;
- break;
- }
- p++;
- cnt -= written;
- leb_needed_cnt = get_leb_cnt(c, cnt);
- dbg_gc("%d znodes remaining, need %d LEBs, have %d", cnt,
- leb_needed_cnt, c->ileb_cnt);
- } while (leb_needed_cnt > c->ileb_cnt);
-
- *p = -1;
- return 0;
-}
-
-/**
- * layout_in_empty_space - layout index nodes in empty space.
- * @c: UBIFS file-system description object
- *
- * This function lays out new index nodes for dirty znodes using empty LEBs.
- *
- * This function returns %0 on success and a negative error code on failure.
- */
-static int layout_in_empty_space(struct ubifs_info *c)
-{
- struct ubifs_znode *znode, *cnext, *zp;
- int lnum, offs, len, next_len, buf_len, buf_offs, used, avail;
- int wlen, blen, err;
-
- cnext = c->enext;
- if (!cnext)
- return 0;
-
- lnum = c->ihead_lnum;
- buf_offs = c->ihead_offs;
-
- buf_len = ubifs_idx_node_sz(c, c->fanout);
- buf_len = ALIGN(buf_len, c->min_io_size);
- used = 0;
- avail = buf_len;
-
- /* Ensure there is enough room for first write */
- next_len = ubifs_idx_node_sz(c, cnext->child_cnt);
- if (buf_offs + next_len > c->leb_size)
- lnum = -1;
-
- while (1) {
- znode = cnext;
-
- len = ubifs_idx_node_sz(c, znode->child_cnt);
-
- /* Determine the index node position */
- if (lnum == -1) {
- if (c->ileb_nxt >= c->ileb_cnt) {
- ubifs_err("out of space");
- return -ENOSPC;
- }
- lnum = c->ilebs[c->ileb_nxt++];
- buf_offs = 0;
- used = 0;
- avail = buf_len;
- }
-
- offs = buf_offs + used;
-
-#ifdef CONFIG_UBIFS_FS_DEBUG
- znode->lnum = lnum;
- znode->offs = offs;
- znode->len = len;
-#endif
-
- /* Update the parent */
- zp = znode->parent;
- if (zp) {
- struct ubifs_zbranch *zbr;
- int i;
-
- i = znode->iip;
- zbr = &zp->zbranch[i];
- zbr->lnum = lnum;
- zbr->offs = offs;
- zbr->len = len;
- } else {
- c->zroot.lnum = lnum;
- c->zroot.offs = offs;
- c->zroot.len = len;
- }
- c->calc_idx_sz += ALIGN(len, 8);
-
- /*
- * Once lprops is updated, we can decrease the dirty znode count
- * but it is easier to just do it here.
- */
- atomic_long_dec(&c->dirty_zn_cnt);
-
- /*
- * Calculate the next index node length to see if there is
- * enough room for it
- */
- cnext = znode->cnext;
- if (cnext == c->cnext)
- next_len = 0;
- else
- next_len = ubifs_idx_node_sz(c, cnext->child_cnt);
-
- if (c->min_io_size == 1) {
- buf_offs += ALIGN(len, 8);
- if (next_len) {
- if (buf_offs + next_len <= c->leb_size)
- continue;
- err = ubifs_update_one_lp(c, lnum, 0,
- c->leb_size - buf_offs, 0, 0);
- if (err)
- return err;
- lnum = -1;
- continue;
- }
- err = ubifs_update_one_lp(c, lnum,
- c->leb_size - buf_offs, 0, 0, 0);
- if (err)
- return err;
- break;
- }
-
- /* Update buffer positions */
- wlen = used + len;
- used += ALIGN(len, 8);
- avail -= ALIGN(len, 8);
-
- if (next_len != 0 &&
- buf_offs + used + next_len <= c->leb_size &&
- avail > 0)
- continue;
-
- if (avail <= 0 && next_len &&
- buf_offs + used + next_len <= c->leb_size)
- blen = buf_len;
- else
- blen = ALIGN(wlen, c->min_io_size);
-
- /* The buffer is full or there are no more znodes to do */
- buf_offs += blen;
- if (next_len) {
- if (buf_offs + next_len > c->leb_size) {
- err = ubifs_update_one_lp(c, lnum,
- c->leb_size - buf_offs, blen - used,
- 0, 0);
- if (err)
- return err;
- lnum = -1;
- }
- used -= blen;
- if (used < 0)
- used = 0;
- avail = buf_len - used;
- continue;
- }
- err = ubifs_update_one_lp(c, lnum, c->leb_size - buf_offs,
- blen - used, 0, 0);
- if (err)
- return err;
- break;
- }
-
-#ifdef CONFIG_UBIFS_FS_DEBUG
- c->new_ihead_lnum = lnum;
- c->new_ihead_offs = buf_offs;
-#endif
-
- return 0;
-}
-
-/**
- * layout_commit - determine positions of index nodes to commit.
- * @c: UBIFS file-system description object
- * @no_space: indicates that insufficient empty LEBs were allocated
- * @cnt: number of znodes to commit
- *
- * Calculate and update the positions of index nodes to commit. If there were
- * an insufficient number of empty LEBs allocated, then index nodes are placed
- * into the gaps created by obsolete index nodes in non-empty index LEBs. For
- * this purpose, an obsolete index node is one that was not in the index as at
- * the end of the last commit. To write "in-the-gaps" requires that those index
- * LEBs are updated atomically in-place.
- */
-static int layout_commit(struct ubifs_info *c, int no_space, int cnt)
-{
- int err;
-
- if (no_space) {
- err = layout_in_gaps(c, cnt);
- if (err)
- return err;
- }
- err = layout_in_empty_space(c);
- return err;
-}
-
-/**
- * find_first_dirty - find first dirty znode.
- * @znode: znode to begin searching from
- */
-static struct ubifs_znode *find_first_dirty(struct ubifs_znode *znode)
-{
- int i, cont;
-
- if (!znode)
- return NULL;
-
- while (1) {
- if (znode->level == 0) {
- if (ubifs_zn_dirty(znode))
- return znode;
- return NULL;
- }
- cont = 0;
- for (i = 0; i < znode->child_cnt; i++) {
- struct ubifs_zbranch *zbr = &znode->zbranch[i];
-
- if (zbr->znode && ubifs_zn_dirty(zbr->znode)) {
- znode = zbr->znode;
- cont = 1;
- break;
- }
- }
- if (!cont) {
- if (ubifs_zn_dirty(znode))
- return znode;
- return NULL;
- }
- }
-}
-
-/**
- * find_next_dirty - find next dirty znode.
- * @znode: znode to begin searching from
- */
-static struct ubifs_znode *find_next_dirty(struct ubifs_znode *znode)
-{
- int n = znode->iip + 1;
-
- znode = znode->parent;
- if (!znode)
- return NULL;
- for (; n < znode->child_cnt; n++) {
- struct ubifs_zbranch *zbr = &znode->zbranch[n];
-
- if (zbr->znode && ubifs_zn_dirty(zbr->znode))
- return find_first_dirty(zbr->znode);
- }
- return znode;
-}
-
-/**
- * get_znodes_to_commit - create list of dirty znodes to commit.
- * @c: UBIFS file-system description object
- *
- * This function returns the number of znodes to commit.
- */
-static int get_znodes_to_commit(struct ubifs_info *c)
-{
- struct ubifs_znode *znode, *cnext;
- int cnt = 0;
-
- c->cnext = find_first_dirty(c->zroot.znode);
- znode = c->enext = c->cnext;
- if (!znode) {
- dbg_cmt("no znodes to commit");
- return 0;
- }
- cnt += 1;
- while (1) {
- ubifs_assert(!test_bit(COW_ZNODE, &znode->flags));
- __set_bit(COW_ZNODE, &znode->flags);
- znode->alt = 0;
- cnext = find_next_dirty(znode);
- if (!cnext) {
- znode->cnext = c->cnext;
- break;
- }
- znode->cnext = cnext;
- znode = cnext;
- cnt += 1;
- }
- dbg_cmt("committing %d znodes", cnt);
- ubifs_assert(cnt == atomic_long_read(&c->dirty_zn_cnt));
- return cnt;
-}
-
-/**
- * alloc_idx_lebs - allocate empty LEBs to be used to commit.
- * @c: UBIFS file-system description object
- * @cnt: number of znodes to commit
- *
- * This function returns %-ENOSPC if it cannot allocate a sufficient number of
- * empty LEBs. %0 is returned on success, otherwise a negative error code
- * is returned.
- */
-static int alloc_idx_lebs(struct ubifs_info *c, int cnt)
-{
- int i, leb_cnt, lnum;
-
- c->ileb_cnt = 0;
- c->ileb_nxt = 0;
- leb_cnt = get_leb_cnt(c, cnt);
- dbg_cmt("need about %d empty LEBS for TNC commit", leb_cnt);
- if (!leb_cnt)
- return 0;
- c->ilebs = kmalloc(leb_cnt * sizeof(int), GFP_NOFS);
- if (!c->ilebs)
- return -ENOMEM;
- for (i = 0; i < leb_cnt; i++) {
- lnum = ubifs_find_free_leb_for_idx(c);
- if (lnum < 0)
- return lnum;
- c->ilebs[c->ileb_cnt++] = lnum;
- dbg_cmt("LEB %d", lnum);
- }
- if (dbg_force_in_the_gaps())
- return -ENOSPC;
- return 0;
-}
-
-/**
- * free_unused_idx_lebs - free unused LEBs that were allocated for the commit.
- * @c: UBIFS file-system description object
- *
- * It is possible that we allocate more empty LEBs for the commit than we need.
- * This functions frees the surplus.
- *
- * This function returns %0 on success and a negative error code on failure.
- */
-static int free_unused_idx_lebs(struct ubifs_info *c)
-{
- int i, err = 0, lnum, er;
-
- for (i = c->ileb_nxt; i < c->ileb_cnt; i++) {
- lnum = c->ilebs[i];
- dbg_cmt("LEB %d", lnum);
- er = ubifs_change_one_lp(c, lnum, LPROPS_NC, LPROPS_NC, 0,
- LPROPS_INDEX | LPROPS_TAKEN, 0);
- if (!err)
- err = er;
- }
- return err;
-}
-
-/**
- * free_idx_lebs - free unused LEBs after commit end.
- * @c: UBIFS file-system description object
- *
- * This function returns %0 on success and a negative error code on failure.
- */
-static int free_idx_lebs(struct ubifs_info *c)
-{
- int err;
-
- err = free_unused_idx_lebs(c);
- kfree(c->ilebs);
- c->ilebs = NULL;
- return err;
-}
-
-/**
- * ubifs_tnc_start_commit - start TNC commit.
- * @c: UBIFS file-system description object
- * @zroot: new index root position is returned here
- *
- * This function prepares the list of indexing nodes to commit and lays out
- * their positions on flash. If there is not enough free space it uses the
- * in-gap commit method. Returns zero in case of success and a negative error
- * code in case of failure.
- */
-int ubifs_tnc_start_commit(struct ubifs_info *c, struct ubifs_zbranch *zroot)
-{
- int err = 0, cnt;
-
- mutex_lock(&c->tnc_mutex);
- err = dbg_check_tnc(c, 1);
- if (err)
- goto out;
- cnt = get_znodes_to_commit(c);
- if (cnt != 0) {
- int no_space = 0;
-
- err = alloc_idx_lebs(c, cnt);
- if (err == -ENOSPC)
- no_space = 1;
- else if (err)
- goto out_free;
- err = layout_commit(c, no_space, cnt);
- if (err)
- goto out_free;
- ubifs_assert(atomic_long_read(&c->dirty_zn_cnt) == 0);
- err = free_unused_idx_lebs(c);
- if (err)
- goto out;
- }
- destroy_old_idx(c);
- memcpy(zroot, &c->zroot, sizeof(struct ubifs_zbranch));
-
- err = ubifs_save_dirty_idx_lnums(c);
- if (err)
- goto out;
-
- spin_lock(&c->space_lock);
- /*
- * Although we have not finished committing yet, update size of the
- * committed index ('c->old_idx_sz') and zero out the index growth
- * budget. It is OK to do this now, because we've reserved all the
- * space which is needed to commit the index, and it is save for the
- * budgeting subsystem to assume the index is already committed,
- * even though it is not.
- */
- c->old_idx_sz = c->calc_idx_sz;
- c->budg_uncommitted_idx = 0;
- spin_unlock(&c->space_lock);
- mutex_unlock(&c->tnc_mutex);
-
- dbg_cmt("number of index LEBs %d", c->lst.idx_lebs);
- dbg_cmt("size of index %llu", c->calc_idx_sz);
- return err;
-
-out_free:
- free_idx_lebs(c);
-out:
- mutex_unlock(&c->tnc_mutex);
- return err;
-}
-
-/**
- * write_index - write index nodes.
- * @c: UBIFS file-system description object
- *
- * This function writes the index nodes whose positions were laid out in the
- * layout_in_empty_space function.
- */
-static int write_index(struct ubifs_info *c)
-{
- struct ubifs_idx_node *idx;
- struct ubifs_znode *znode, *cnext;
- int i, lnum, offs, len, next_len, buf_len, buf_offs, used;
- int avail, wlen, err, lnum_pos = 0;
-
- cnext = c->enext;
- if (!cnext)
- return 0;
-
- /*
- * Always write index nodes to the index head so that index nodes and
- * other types of nodes are never mixed in the same erase block.
- */
- lnum = c->ihead_lnum;
- buf_offs = c->ihead_offs;
-
- /* Allocate commit buffer */
- buf_len = ALIGN(c->max_idx_node_sz, c->min_io_size);
- used = 0;
- avail = buf_len;
-
- /* Ensure there is enough room for first write */
- next_len = ubifs_idx_node_sz(c, cnext->child_cnt);
- if (buf_offs + next_len > c->leb_size) {
- err = ubifs_update_one_lp(c, lnum, LPROPS_NC, 0, 0,
- LPROPS_TAKEN);
- if (err)
- return err;
- lnum = -1;
- }
-
- while (1) {
- cond_resched();
-
- znode = cnext;
- idx = c->cbuf + used;
-
- /* Make index node */
- idx->ch.node_type = UBIFS_IDX_NODE;
- idx->child_cnt = cpu_to_le16(znode->child_cnt);
- idx->level = cpu_to_le16(znode->level);
- for (i = 0; i < znode->child_cnt; i++) {
- struct ubifs_branch *br = ubifs_idx_branch(c, idx, i);
- struct ubifs_zbranch *zbr = &znode->zbranch[i];
-
- key_write_idx(c, &zbr->key, &br->key);
- br->lnum = cpu_to_le32(zbr->lnum);
- br->offs = cpu_to_le32(zbr->offs);
- br->len = cpu_to_le32(zbr->len);
- if (!zbr->lnum || !zbr->len) {
- ubifs_err("bad ref in znode");
- dbg_dump_znode(c, znode);
- if (zbr->znode)
- dbg_dump_znode(c, zbr->znode);
- }
- }
- len = ubifs_idx_node_sz(c, znode->child_cnt);
- ubifs_prepare_node(c, idx, len, 0);
-
- /* Determine the index node position */
- if (lnum == -1) {
- lnum = c->ilebs[lnum_pos++];
- buf_offs = 0;
- used = 0;
- avail = buf_len;
- }
- offs = buf_offs + used;
-
-#ifdef CONFIG_UBIFS_FS_DEBUG
- if (lnum != znode->lnum || offs != znode->offs ||
- len != znode->len) {
- ubifs_err("inconsistent znode posn");
- return -EINVAL;
- }
-#endif
-
- /* Grab some stuff from znode while we still can */
- cnext = znode->cnext;
-
- ubifs_assert(ubifs_zn_dirty(znode));
- ubifs_assert(test_bit(COW_ZNODE, &znode->flags));
-
- /*
- * It is important that other threads should see %DIRTY_ZNODE
- * flag cleared before %COW_ZNODE. Specifically, it matters in
- * the 'dirty_cow_znode()' function. This is the reason for the
- * first barrier. Also, we want the bit changes to be seen to
- * other threads ASAP, to avoid unnecesarry copying, which is
- * the reason for the second barrier.
- */
- clear_bit(DIRTY_ZNODE, &znode->flags);
- smp_mb__before_clear_bit();
- clear_bit(COW_ZNODE, &znode->flags);
- smp_mb__after_clear_bit();
-
- /* Do not access znode from this point on */
-
- /* Update buffer positions */
- wlen = used + len;
- used += ALIGN(len, 8);
- avail -= ALIGN(len, 8);
-
- /*
- * Calculate the next index node length to see if there is
- * enough room for it
- */
- if (cnext == c->cnext)
- next_len = 0;
- else
- next_len = ubifs_idx_node_sz(c, cnext->child_cnt);
-
- if (c->min_io_size == 1) {
- /*
- * Write the prepared index node immediately if there is
- * no minimum IO size
- */
- err = ubifs_leb_write(c, lnum, c->cbuf, buf_offs,
- wlen, UBI_SHORTTERM);
- if (err)
- return err;
- buf_offs += ALIGN(wlen, 8);
- if (next_len) {
- used = 0;
- avail = buf_len;
- if (buf_offs + next_len > c->leb_size) {
- err = ubifs_update_one_lp(c, lnum,
- LPROPS_NC, 0, 0, LPROPS_TAKEN);
- if (err)
- return err;
- lnum = -1;
- }
- continue;
- }
- } else {
- int blen, nxt_offs = buf_offs + used + next_len;
-
- if (next_len && nxt_offs <= c->leb_size) {
- if (avail > 0)
- continue;
- else
- blen = buf_len;
- } else {
- wlen = ALIGN(wlen, 8);
- blen = ALIGN(wlen, c->min_io_size);
- ubifs_pad(c, c->cbuf + wlen, blen - wlen);
- }
- /*
- * The buffer is full or there are no more znodes
- * to do
- */
- err = ubifs_leb_write(c, lnum, c->cbuf, buf_offs,
- blen, UBI_SHORTTERM);
- if (err)
- return err;
- buf_offs += blen;
- if (next_len) {
- if (nxt_offs > c->leb_size) {
- err = ubifs_update_one_lp(c, lnum,
- LPROPS_NC, 0, 0, LPROPS_TAKEN);
- if (err)
- return err;
- lnum = -1;
- }
- used -= blen;
- if (used < 0)
- used = 0;
- avail = buf_len - used;
- memmove(c->cbuf, c->cbuf + blen, used);
- continue;
- }
- }
- break;
- }
-
-#ifdef CONFIG_UBIFS_FS_DEBUG
- if (lnum != c->new_ihead_lnum || buf_offs != c->new_ihead_offs) {
- ubifs_err("inconsistent ihead");
- return -EINVAL;
- }
-#endif
-
- c->ihead_lnum = lnum;
- c->ihead_offs = buf_offs;
-
- return 0;
-}
-
-/**
- * free_obsolete_znodes - free obsolete znodes.
- * @c: UBIFS file-system description object
- *
- * At the end of commit end, obsolete znodes are freed.
- */
-static void free_obsolete_znodes(struct ubifs_info *c)
-{
- struct ubifs_znode *znode, *cnext;
-
- cnext = c->cnext;
- do {
- znode = cnext;
- cnext = znode->cnext;
- if (test_bit(OBSOLETE_ZNODE, &znode->flags))
- kfree(znode);
- else {
- znode->cnext = NULL;
- atomic_long_inc(&c->clean_zn_cnt);
- atomic_long_inc(&ubifs_clean_zn_cnt);
- }
- } while (cnext != c->cnext);
-}
-
-/**
- * return_gap_lebs - return LEBs used by the in-gap commit method.
- * @c: UBIFS file-system description object
- *
- * This function clears the "taken" flag for the LEBs which were used by the
- * "commit in-the-gaps" method.
- */
-static int return_gap_lebs(struct ubifs_info *c)
-{
- int *p, err;
-
- if (!c->gap_lebs)
- return 0;
-
- dbg_cmt("");
- for (p = c->gap_lebs; *p != -1; p++) {
- err = ubifs_change_one_lp(c, *p, LPROPS_NC, LPROPS_NC, 0,
- LPROPS_TAKEN, 0);
- if (err)
- return err;
- }
-
- kfree(c->gap_lebs);
- c->gap_lebs = NULL;
- return 0;
-}
-
-/**
- * ubifs_tnc_end_commit - update the TNC for commit end.
- * @c: UBIFS file-system description object
- *
- * Write the dirty znodes.
- */
-int ubifs_tnc_end_commit(struct ubifs_info *c)
-{
- int err;
-
- if (!c->cnext)
- return 0;
-
- err = return_gap_lebs(c);
- if (err)
- return err;
-
- err = write_index(c);
- if (err)
- return err;
-
- mutex_lock(&c->tnc_mutex);
-
- dbg_cmt("TNC height is %d", c->zroot.znode->level + 1);
-
- free_obsolete_znodes(c);
-
- c->cnext = NULL;
- kfree(c->ilebs);
- c->ilebs = NULL;
-
- mutex_unlock(&c->tnc_mutex);
-
- return 0;
-}
projects / u-boot / commitdiff