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Diffstat (limited to 'fs/ubifs/lpt.c')
| -rw-r--r-- | fs/ubifs/lpt.c | 2243 |
1 files changed, 2243 insertions, 0 deletions
diff --git a/fs/ubifs/lpt.c b/fs/ubifs/lpt.c new file mode 100644 index 00000000000..9ff2463177e --- /dev/null +++ b/fs/ubifs/lpt.c @@ -0,0 +1,2243 @@ +/* + * 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 LEB properties tree (LPT) area. The LPT area + * contains the LEB properties tree, a table of LPT area eraseblocks (ltab), and + * (for the "big" model) a table of saved LEB numbers (lsave). The LPT area sits + * between the log and the orphan area. + * + * The LPT area is like a miniature self-contained file system. It is required + * that it never runs out of space, is fast to access and update, and scales + * logarithmically. The LEB properties tree is implemented as a wandering tree + * much like the TNC, and the LPT area has its own garbage collection. + * + * The LPT has two slightly different forms called the "small model" and the + * "big model". The small model is used when the entire LEB properties table + * can be written into a single eraseblock. In that case, garbage collection + * consists of just writing the whole table, which therefore makes all other + * eraseblocks reusable. In the case of the big model, dirty eraseblocks are + * selected for garbage collection, which consists are marking the nodes in + * that LEB as dirty, and then only the dirty nodes are written out. Also, in + * the case of the big model, a table of LEB numbers is saved so that the entire + * LPT does not to be scanned looking for empty eraseblocks when UBIFS is first + * mounted. + */ + +#include <linux/crc16.h> +#include "ubifs.h" + +/** + * do_calc_lpt_geom - calculate sizes for the LPT area. + * @c: the UBIFS file-system description object + * + * Calculate the sizes of LPT bit fields, nodes, and tree, based on the + * properties of the flash and whether LPT is "big" (c->big_lpt). + */ +static void do_calc_lpt_geom(struct ubifs_info *c) +{ + int i, n, bits, per_leb_wastage, max_pnode_cnt; + long long sz, tot_wastage; + + n = c->main_lebs + c->max_leb_cnt - c->leb_cnt; + max_pnode_cnt = DIV_ROUND_UP(n, UBIFS_LPT_FANOUT); + + c->lpt_hght = 1; + n = UBIFS_LPT_FANOUT; + while (n < max_pnode_cnt) { + c->lpt_hght += 1; + n <<= UBIFS_LPT_FANOUT_SHIFT; + } + + c->pnode_cnt = DIV_ROUND_UP(c->main_lebs, UBIFS_LPT_FANOUT); + + n = DIV_ROUND_UP(c->pnode_cnt, UBIFS_LPT_FANOUT); + c->nnode_cnt = n; + for (i = 1; i < c->lpt_hght; i++) { + n = DIV_ROUND_UP(n, UBIFS_LPT_FANOUT); + c->nnode_cnt += n; + } + + c->space_bits = fls(c->leb_size) - 3; + c->lpt_lnum_bits = fls(c->lpt_lebs); + c->lpt_offs_bits = fls(c->leb_size - 1); + c->lpt_spc_bits = fls(c->leb_size); + + n = DIV_ROUND_UP(c->max_leb_cnt, UBIFS_LPT_FANOUT); + c->pcnt_bits = fls(n - 1); + + c->lnum_bits = fls(c->max_leb_cnt - 1); + + bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS + + (c->big_lpt ? c->pcnt_bits : 0) + + (c->space_bits * 2 + 1) * UBIFS_LPT_FANOUT; + c->pnode_sz = (bits + 7) / 8; + + bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS + + (c->big_lpt ? c->pcnt_bits : 0) + + (c->lpt_lnum_bits + c->lpt_offs_bits) * UBIFS_LPT_FANOUT; + c->nnode_sz = (bits + 7) / 8; + + bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS + + c->lpt_lebs * c->lpt_spc_bits * 2; + c->ltab_sz = (bits + 7) / 8; + + bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS + + c->lnum_bits * c->lsave_cnt; + c->lsave_sz = (bits + 7) / 8; + + /* Calculate the minimum LPT size */ + c->lpt_sz = (long long)c->pnode_cnt * c->pnode_sz; + c->lpt_sz += (long long)c->nnode_cnt * c->nnode_sz; + c->lpt_sz += c->ltab_sz; + c->lpt_sz += c->lsave_sz; + + /* Add wastage */ + sz = c->lpt_sz; + per_leb_wastage = max_t(int, c->pnode_sz, c->nnode_sz); + sz += per_leb_wastage; + tot_wastage = per_leb_wastage; + while (sz > c->leb_size) { + sz += per_leb_wastage; + sz -= c->leb_size; + tot_wastage += per_leb_wastage; + } + tot_wastage += ALIGN(sz, c->min_io_size) - sz; + c->lpt_sz += tot_wastage; +} + +/** + * ubifs_calc_lpt_geom - calculate and check sizes for the LPT area. + * @c: the UBIFS file-system description object + * + * This function returns %0 on success and a negative error code on failure. + */ +int ubifs_calc_lpt_geom(struct ubifs_info *c) +{ + int lebs_needed; + uint64_t sz; + + do_calc_lpt_geom(c); + + /* Verify that lpt_lebs is big enough */ + sz = c->lpt_sz * 2; /* Must have at least 2 times the size */ + sz += c->leb_size - 1; + do_div(sz, c->leb_size); + lebs_needed = sz; + if (lebs_needed > c->lpt_lebs) { + ubifs_err("too few LPT LEBs"); + return -EINVAL; + } + + /* Verify that ltab fits in a single LEB (since ltab is a single node */ + if (c->ltab_sz > c->leb_size) { + ubifs_err("LPT ltab too big"); + return -EINVAL; + } + + c->check_lpt_free = c->big_lpt; + + return 0; +} + +/** + * calc_dflt_lpt_geom - calculate default LPT geometry. + * @c: the UBIFS file-system description object + * @main_lebs: number of main area LEBs is passed and returned here + * @big_lpt: whether the LPT area is "big" is returned here + * + * The size of the LPT area depends on parameters that themselves are dependent + * on the size of the LPT area. This function, successively recalculates the LPT + * area geometry until the parameters and resultant geometry are consistent. + * + * This function returns %0 on success and a negative error code on failure. + */ +static int calc_dflt_lpt_geom(struct ubifs_info *c, int *main_lebs, + int *big_lpt) +{ + int i, lebs_needed; + uint64_t sz; + + /* Start by assuming the minimum number of LPT LEBs */ + c->lpt_lebs = UBIFS_MIN_LPT_LEBS; + c->main_lebs = *main_lebs - c->lpt_lebs; + if (c->main_lebs <= 0) + return -EINVAL; + + /* And assume we will use the small LPT model */ + c->big_lpt = 0; + + /* + * Calculate the geometry based on assumptions above and then see if it + * makes sense + */ + do_calc_lpt_geom(c); + + /* Small LPT model must have lpt_sz < leb_size */ + if (c->lpt_sz > c->leb_size) { + /* Nope, so try again using big LPT model */ + c->big_lpt = 1; + do_calc_lpt_geom(c); + } + + /* Now check there are enough LPT LEBs */ + for (i = 0; i < 64 ; i++) { + sz = c->lpt_sz * 4; /* Allow 4 times the size */ + sz += c->leb_size - 1; + do_div(sz, c->leb_size); + lebs_needed = sz; + if (lebs_needed > c->lpt_lebs) { + /* Not enough LPT LEBs so try again with more */ + c->lpt_lebs = lebs_needed; + c->main_lebs = *main_lebs - c->lpt_lebs; + if (c->main_lebs <= 0) + return -EINVAL; + do_calc_lpt_geom(c); + continue; + } + if (c->ltab_sz > c->leb_size) { + ubifs_err("LPT ltab too big"); + return -EINVAL; + } + *main_lebs = c->main_lebs; + *big_lpt = c->big_lpt; + return 0; + } + return -EINVAL; +} + +/** + * pack_bits - pack bit fields end-to-end. + * @addr: address at which to pack (passed and next address returned) + * @pos: bit position at which to pack (passed and next position returned) + * @val: value to pack + * @nrbits: number of bits of value to pack (1-32) + */ +static void pack_bits(uint8_t **addr, int *pos, uint32_t val, int nrbits) +{ + uint8_t *p = *addr; + int b = *pos; + + ubifs_assert(nrbits > 0); + ubifs_assert(nrbits <= 32); + ubifs_assert(*pos >= 0); + ubifs_assert(*pos < 8); + ubifs_assert((val >> nrbits) == 0 || nrbits == 32); + if (b) { + *p |= ((uint8_t)val) << b; + nrbits += b; + if (nrbits > 8) { + *++p = (uint8_t)(val >>= (8 - b)); + if (nrbits > 16) { + *++p = (uint8_t)(val >>= 8); + if (nrbits > 24) { + *++p = (uint8_t)(val >>= 8); + if (nrbits > 32) + *++p = (uint8_t)(val >>= 8); + } + } + } + } else { + *p = (uint8_t)val; + if (nrbits > 8) { + *++p = (uint8_t)(val >>= 8); + if (nrbits > 16) { + *++p = (uint8_t)(val >>= 8); + if (nrbits > 24) + *++p = (uint8_t)(val >>= 8); + } + } + } + b = nrbits & 7; + if (b == 0) + p++; + *addr = p; + *pos = b; +} + +/** + * ubifs_unpack_bits - unpack bit fields. + * @addr: address at which to unpack (passed and next address returned) + * @pos: bit position at which to unpack (passed and next position returned) + * @nrbits: number of bits of value to unpack (1-32) + * + * This functions returns the value unpacked. + */ +uint32_t ubifs_unpack_bits(uint8_t **addr, int *pos, int nrbits) +{ + const int k = 32 - nrbits; + uint8_t *p = *addr; + int b = *pos; + uint32_t val; + + ubifs_assert(nrbits > 0); + ubifs_assert(nrbits <= 32); + ubifs_assert(*pos >= 0); + ubifs_assert(*pos < 8); + if (b) { + val = p[1] | ((uint32_t)p[2] << 8) | ((uint32_t)p[3] << 16) | + ((uint32_t)p[4] << 24); + val <<= (8 - b); + val |= *p >> b; + nrbits += b; + } else + val = p[0] | ((uint32_t)p[1] << 8) | ((uint32_t)p[2] << 16) | + ((uint32_t)p[3] << 24); + val <<= k; + val >>= k; + b = nrbits & 7; + p += nrbits / 8; + *addr = p; + *pos = b; + ubifs_assert((val >> nrbits) == 0 || nrbits - b == 32); + return val; +} + +/** + * ubifs_pack_pnode - pack all the bit fields of a pnode. + * @c: UBIFS file-system description object + * @buf: buffer into which to pack + * @pnode: pnode to pack + */ +void ubifs_pack_pnode(struct ubifs_info *c, void *buf, + struct ubifs_pnode *pnode) +{ + uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES; + int i, pos = 0; + uint16_t crc; + + pack_bits(&addr, &pos, UBIFS_LPT_PNODE, UBIFS_LPT_TYPE_BITS); + if (c->big_lpt) + pack_bits(&addr, &pos, pnode->num, c->pcnt_bits); + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + pack_bits(&addr, &pos, pnode->lprops[i].free >> 3, + c->space_bits); + pack_bits(&addr, &pos, pnode->lprops[i].dirty >> 3, + c->space_bits); + if (pnode->lprops[i].flags & LPROPS_INDEX) + pack_bits(&addr, &pos, 1, 1); + else + pack_bits(&addr, &pos, 0, 1); + } + crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES, + c->pnode_sz - UBIFS_LPT_CRC_BYTES); + addr = buf; + pos = 0; + pack_bits(&addr, &pos, crc, UBIFS_LPT_CRC_BITS); +} + +/** + * ubifs_pack_nnode - pack all the bit fields of a nnode. + * @c: UBIFS file-system description object + * @buf: buffer into which to pack + * @nnode: nnode to pack + */ +void ubifs_pack_nnode(struct ubifs_info *c, void *buf, + struct ubifs_nnode *nnode) +{ + uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES; + int i, pos = 0; + uint16_t crc; + + pack_bits(&addr, &pos, UBIFS_LPT_NNODE, UBIFS_LPT_TYPE_BITS); + if (c->big_lpt) + pack_bits(&addr, &pos, nnode->num, c->pcnt_bits); + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + int lnum = nnode->nbranch[i].lnum; + + if (lnum == 0) + lnum = c->lpt_last + 1; + pack_bits(&addr, &pos, lnum - c->lpt_first, c->lpt_lnum_bits); + pack_bits(&addr, &pos, nnode->nbranch[i].offs, + c->lpt_offs_bits); + } + crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES, + c->nnode_sz - UBIFS_LPT_CRC_BYTES); + addr = buf; + pos = 0; + pack_bits(&addr, &pos, crc, UBIFS_LPT_CRC_BITS); +} + +/** + * ubifs_pack_ltab - pack the LPT's own lprops table. + * @c: UBIFS file-system description object + * @buf: buffer into which to pack + * @ltab: LPT's own lprops table to pack + */ +void ubifs_pack_ltab(struct ubifs_info *c, void *buf, + struct ubifs_lpt_lprops *ltab) +{ + uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES; + int i, pos = 0; + uint16_t crc; + + pack_bits(&addr, &pos, UBIFS_LPT_LTAB, UBIFS_LPT_TYPE_BITS); + for (i = 0; i < c->lpt_lebs; i++) { + pack_bits(&addr, &pos, ltab[i].free, c->lpt_spc_bits); + pack_bits(&addr, &pos, ltab[i].dirty, c->lpt_spc_bits); + } + crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES, + c->ltab_sz - UBIFS_LPT_CRC_BYTES); + addr = buf; + pos = 0; + pack_bits(&addr, &pos, crc, UBIFS_LPT_CRC_BITS); +} + +/** + * ubifs_pack_lsave - pack the LPT's save table. + * @c: UBIFS file-system description object + * @buf: buffer into which to pack + * @lsave: LPT's save table to pack + */ +void ubifs_pack_lsave(struct ubifs_info *c, void *buf, int *lsave) +{ + uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES; + int i, pos = 0; + uint16_t crc; + + pack_bits(&addr, &pos, UBIFS_LPT_LSAVE, UBIFS_LPT_TYPE_BITS); + for (i = 0; i < c->lsave_cnt; i++) + pack_bits(&addr, &pos, lsave[i], c->lnum_bits); + crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES, + c->lsave_sz - UBIFS_LPT_CRC_BYTES); + addr = buf; + pos = 0; + pack_bits(&addr, &pos, crc, UBIFS_LPT_CRC_BITS); +} + +/** + * ubifs_add_lpt_dirt - add dirty space to LPT LEB properties. + * @c: UBIFS file-system description object + * @lnum: LEB number to which to add dirty space + * @dirty: amount of dirty space to add + */ +void ubifs_add_lpt_dirt(struct ubifs_info *c, int lnum, int dirty) +{ + if (!dirty || !lnum) + return; + dbg_lp("LEB %d add %d to %d", + lnum, dirty, c->ltab[lnum - c->lpt_first].dirty); + ubifs_assert(lnum >= c->lpt_first && lnum <= c->lpt_last); + c->ltab[lnum - c->lpt_first].dirty += dirty; +} + +/** + * set_ltab - set LPT LEB properties. + * @c: UBIFS file-system description object + * @lnum: LEB number + * @free: amount of free space + * @dirty: amount of dirty space + */ +static void set_ltab(struct ubifs_info *c, int lnum, int free, int dirty) +{ + dbg_lp("LEB %d free %d dirty %d to %d %d", + lnum, c->ltab[lnum - c->lpt_first].free, + c->ltab[lnum - c->lpt_first].dirty, free, dirty); + ubifs_assert(lnum >= c->lpt_first && lnum <= c->lpt_last); + c->ltab[lnum - c->lpt_first].free = free; + c->ltab[lnum - c->lpt_first].dirty = dirty; +} + +/** + * ubifs_add_nnode_dirt - add dirty space to LPT LEB properties. + * @c: UBIFS file-system description object + * @nnode: nnode for which to add dirt + */ +void ubifs_add_nnode_dirt(struct ubifs_info *c, struct ubifs_nnode *nnode) +{ + struct ubifs_nnode *np = nnode->parent; + + if (np) + ubifs_add_lpt_dirt(c, np->nbranch[nnode->iip].lnum, + c->nnode_sz); + else { + ubifs_add_lpt_dirt(c, c->lpt_lnum, c->nnode_sz); + if (!(c->lpt_drty_flgs & LTAB_DIRTY)) { + c->lpt_drty_flgs |= LTAB_DIRTY; + ubifs_add_lpt_dirt(c, c->ltab_lnum, c->ltab_sz); + } + } +} + +/** + * add_pnode_dirt - add dirty space to LPT LEB properties. + * @c: UBIFS file-system description object + * @pnode: pnode for which to add dirt + */ +static void add_pnode_dirt(struct ubifs_info *c, struct ubifs_pnode *pnode) +{ + ubifs_add_lpt_dirt(c, pnode->parent->nbranch[pnode->iip].lnum, + c->pnode_sz); +} + +/** + * calc_nnode_num - calculate nnode number. + * @row: the row in the tree (root is zero) + * @col: the column in the row (leftmost is zero) + * + * The nnode number is a number that uniquely identifies a nnode and can be used + * easily to traverse the tree from the root to that nnode. + * + * This function calculates and returns the nnode number for the nnode at @row + * and @col. + */ +static int calc_nnode_num(int row, int col) +{ + int num, bits; + + num = 1; + while (row--) { + bits = (col & (UBIFS_LPT_FANOUT - 1)); + col >>= UBIFS_LPT_FANOUT_SHIFT; + num <<= UBIFS_LPT_FANOUT_SHIFT; + num |= bits; + } + return num; +} + +/** + * calc_nnode_num_from_parent - calculate nnode number. + * @c: UBIFS file-system description object + * @parent: parent nnode + * @iip: index in parent + * + * The nnode number is a number that uniquely identifies a nnode and can be used + * easily to traverse the tree from the root to that nnode. + * + * This function calculates and returns the nnode number based on the parent's + * nnode number and the index in parent. + */ +static int calc_nnode_num_from_parent(struct ubifs_info *c, + struct ubifs_nnode *parent, int iip) +{ + int num, shft; + + if (!parent) + return 1; + shft = (c->lpt_hght - parent->level) * UBIFS_LPT_FANOUT_SHIFT; + num = parent->num ^ (1 << shft); + num |= (UBIFS_LPT_FANOUT + iip) << shft; + return num; +} + +/** + * calc_pnode_num_from_parent - calculate pnode number. + * @c: UBIFS file-system description object + * @parent: parent nnode + * @iip: index in parent + * + * The pnode number is a number that uniquely identifies a pnode and can be used + * easily to traverse the tree from the root to that pnode. + * + * This function calculates and returns the pnode number based on the parent's + * nnode number and the index in parent. + */ +static int calc_pnode_num_from_parent(struct ubifs_info *c, + struct ubifs_nnode *parent, int iip) +{ + int i, n = c->lpt_hght - 1, pnum = parent->num, num = 0; + + for (i = 0; i < n; i++) { + num <<= UBIFS_LPT_FANOUT_SHIFT; + num |= pnum & (UBIFS_LPT_FANOUT - 1); + pnum >>= UBIFS_LPT_FANOUT_SHIFT; + } + num <<= UBIFS_LPT_FANOUT_SHIFT; + num |= iip; + return num; +} + +/** + * ubifs_create_dflt_lpt - create default LPT. + * @c: UBIFS file-system description object + * @main_lebs: number of main area LEBs is passed and returned here + * @lpt_first: LEB number of first LPT LEB + * @lpt_lebs: number of LEBs for LPT is passed and returned here + * @big_lpt: use big LPT model is passed and returned here + * + * This function returns %0 on success and a negative error code on failure. + */ +int ubifs_create_dflt_lpt(struct ubifs_info *c, int *main_lebs, int lpt_first, + int *lpt_lebs, int *big_lpt) +{ + int lnum, err = 0, node_sz, iopos, i, j, cnt, len, alen, row; + int blnum, boffs, bsz, bcnt; + struct ubifs_pnode *pnode = NULL; + struct ubifs_nnode *nnode = NULL; + void *buf = NULL, *p; + struct ubifs_lpt_lprops *ltab = NULL; + int *lsave = NULL; + + err = calc_dflt_lpt_geom(c, main_lebs, big_lpt); + if (err) + return err; + *lpt_lebs = c->lpt_lebs; + + /* Needed by 'ubifs_pack_nnode()' and 'set_ltab()' */ + c->lpt_first = lpt_first; + /* Needed by 'set_ltab()' */ + c->lpt_last = lpt_first + c->lpt_lebs - 1; + /* Needed by 'ubifs_pack_lsave()' */ + c->main_first = c->leb_cnt - *main_lebs; + + lsave = kmalloc(sizeof(int) * c->lsave_cnt, GFP_KERNEL); + pnode = kzalloc(sizeof(struct ubifs_pnode), GFP_KERNEL); + nnode = kzalloc(sizeof(struct ubifs_nnode), GFP_KERNEL); + buf = vmalloc(c->leb_size); + ltab = vmalloc(sizeof(struct ubifs_lpt_lprops) * c->lpt_lebs); + if (!pnode || !nnode || !buf || !ltab || !lsave) { + err = -ENOMEM; + goto out; + } + + ubifs_assert(!c->ltab); + c->ltab = ltab; /* Needed by set_ltab */ + + /* Initialize LPT's own lprops */ + for (i = 0; i < c->lpt_lebs; i++) { + ltab[i].free = c->leb_size; + ltab[i].dirty = 0; + ltab[i].tgc = 0; + ltab[i].cmt = 0; + } + + lnum = lpt_first; + p = buf; + /* Number of leaf nodes (pnodes) */ + cnt = c->pnode_cnt; + + /* + * The first pnode contains the LEB properties for the LEBs that contain + * the root inode node and the root index node of the index tree. + */ + node_sz = ALIGN(ubifs_idx_node_sz(c, 1), 8); + iopos = ALIGN(node_sz, c->min_io_size); + pnode->lprops[0].free = c->leb_size - iopos; + pnode->lprops[0].dirty = iopos - node_sz; + pnode->lprops[0].flags = LPROPS_INDEX; + + node_sz = UBIFS_INO_NODE_SZ; + iopos = ALIGN(node_sz, c->min_io_size); + pnode->lprops[1].free = c->leb_size - iopos; + pnode->lprops[1].dirty = iopos - node_sz; + + for (i = 2; i < UBIFS_LPT_FANOUT; i++) + pnode->lprops[i].free = c->leb_size; + + /* Add first pnode */ + ubifs_pack_pnode(c, p, pnode); + p += c->pnode_sz; + len = c->pnode_sz; + pnode->num += 1; + + /* Reset pnode values for remaining pnodes */ + pnode->lprops[0].free = c->leb_size; + pnode->lprops[0].dirty = 0; + pnode->lprops[0].flags = 0; + + pnode->lprops[1].free = c->leb_size; + pnode->lprops[1].dirty = 0; + + /* + * To calculate the internal node branches, we keep information about + * the level below. + */ + blnum = lnum; /* LEB number of level below */ + boffs = 0; /* Offset of level below */ + bcnt = cnt; /* Number of nodes in level below */ + bsz = c->pnode_sz; /* Size of nodes in level below */ + + /* Add all remaining pnodes */ + for (i = 1; i < cnt; i++) { + if (len + c->pnode_sz > c->leb_size) { + alen = ALIGN(len, c->min_io_size); + set_ltab(c, lnum, c->leb_size - alen, alen - len); + memset(p, 0xff, alen - len); + err = ubi_leb_change(c->ubi, lnum++, buf, alen, + UBI_SHORTTERM); + if (err) + goto out; + p = buf; + len = 0; + } + ubifs_pack_pnode(c, p, pnode); + p += c->pnode_sz; + len += c->pnode_sz; + /* + * pnodes are simply numbered left to right starting at zero, + * which means the pnode number can be used easily to traverse + * down the tree to the corresponding pnode. + */ + pnode->num += 1; + } + + row = 0; + for (i = UBIFS_LPT_FANOUT; cnt > i; i <<= UBIFS_LPT_FANOUT_SHIFT) + row += 1; + /* Add all nnodes, one level at a time */ + while (1) { + /* Number of internal nodes (nnodes) at next level */ + cnt = DIV_ROUND_UP(cnt, UBIFS_LPT_FANOUT); + for (i = 0; i < cnt; i++) { + if (len + c->nnode_sz > c->leb_size) { + alen = ALIGN(len, c->min_io_size); + set_ltab(c, lnum, c->leb_size - alen, + alen - len); + memset(p, 0xff, alen - len); + err = ubi_leb_change(c->ubi, lnum++, buf, alen, + UBI_SHORTTERM); + if (err) + goto out; + p = buf; + len = 0; + } + /* Only 1 nnode at this level, so it is the root */ + if (cnt == 1) { + c->lpt_lnum = lnum; + c->lpt_offs = len; + } + /* Set branches to the level below */ + for (j = 0; j < UBIFS_LPT_FANOUT; j++) { + if (bcnt) { + if (boffs + bsz > c->leb_size) { + blnum += 1; + boffs = 0; + } + nnode->nbranch[j].lnum = blnum; + nnode->nbranch[j].offs = boffs; + boffs += bsz; + bcnt--; + } else { + nnode->nbranch[j].lnum = 0; + nnode->nbranch[j].offs = 0; + } + } + nnode->num = calc_nnode_num(row, i); + ubifs_pack_nnode(c, p, nnode); + p += c->nnode_sz; + len += c->nnode_sz; + } + /* Only 1 nnode at this level, so it is the root */ + if (cnt == 1) + break; + /* Update the information about the level below */ + bcnt = cnt; + bsz = c->nnode_sz; + row -= 1; + } + + if (*big_lpt) { + /* Need to add LPT's save table */ + if (len + c->lsave_sz > c->leb_size) { + alen = ALIGN(len, c->min_io_size); + set_ltab(c, lnum, c->leb_size - alen, alen - len); + memset(p, 0xff, alen - len); + err = ubi_leb_change(c->ubi, lnum++, buf, alen, + UBI_SHORTTERM); + if (err) + goto out; + p = buf; + len = 0; + } + + c->lsave_lnum = lnum; + c->lsave_offs = len; + + for (i = 0; i < c->lsave_cnt && i < *main_lebs; i++) + lsave[i] = c->main_first + i; + for (; i < c->lsave_cnt; i++) + lsave[i] = c->main_first; + + ubifs_pack_lsave(c, p, lsave); + p += c->lsave_sz; + len += c->lsave_sz; + } + + /* Need to add LPT's own LEB properties table */ + if (len + c->ltab_sz > c->leb_size) { + alen = ALIGN(len, c->min_io_size); + set_ltab(c, lnum, c->leb_size - alen, alen - len); + memset(p, 0xff, alen - len); + err = ubi_leb_change(c->ubi, lnum++, buf, alen, UBI_SHORTTERM); + if (err) + goto out; + p = buf; + len = 0; + } + + c->ltab_lnum = lnum; + c->ltab_offs = len; + + /* Update ltab before packing it */ + len += c->ltab_sz; + alen = ALIGN(len, c->min_io_size); + set_ltab(c, lnum, c->leb_size - alen, alen - len); + + ubifs_pack_ltab(c, p, ltab); + p += c->ltab_sz; + + /* Write remaining buffer */ + memset(p, 0xff, alen - len); + err = ubi_leb_change(c->ubi, lnum, buf, alen, UBI_SHORTTERM); + if (err) + goto out; + + c->nhead_lnum = lnum; + c->nhead_offs = ALIGN(len, c->min_io_size); + + dbg_lp("space_bits %d", c->space_bits); + dbg_lp("lpt_lnum_bits %d", c->lpt_lnum_bits); + dbg_lp("lpt_offs_bits %d", c->lpt_offs_bits); + dbg_lp("lpt_spc_bits %d", c->lpt_spc_bits); + dbg_lp("pcnt_bits %d", c->pcnt_bits); + dbg_lp("lnum_bits %d", c->lnum_bits); + dbg_lp("pnode_sz %d", c->pnode_sz); + dbg_lp("nnode_sz %d", c->nnode_sz); + dbg_lp("ltab_sz %d", c->ltab_sz); + dbg_lp("lsave_sz %d", c->lsave_sz); + dbg_lp("lsave_cnt %d", c->lsave_cnt); + dbg_lp("lpt_hght %d", c->lpt_hght); + dbg_lp("big_lpt %d", c->big_lpt); + dbg_lp("LPT root is at %d:%d", c->lpt_lnum, c->lpt_offs); + dbg_lp("LPT head is at %d:%d", c->nhead_lnum, c->nhead_offs); + dbg_lp("LPT ltab is at %d:%d", c->ltab_lnum, c->ltab_offs); + if (c->big_lpt) + dbg_lp("LPT lsave is at %d:%d", c->lsave_lnum, c->lsave_offs); +out: + c->ltab = NULL; + kfree(lsave); + vfree(ltab); + vfree(buf); + kfree(nnode); + kfree(pnode); + return err; +} + +/** + * update_cats - add LEB properties of a pnode to LEB category lists and heaps. + * @c: UBIFS file-system description object + * @pnode: pnode + * + * When a pnode is loaded into memory, the LEB properties it contains are added, + * by this function, to the LEB category lists and heaps. + */ +static void update_cats(struct ubifs_info *c, struct ubifs_pnode *pnode) +{ + int i; + + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + int cat = pnode->lprops[i].flags & LPROPS_CAT_MASK; + int lnum = pnode->lprops[i].lnum; + + if (!lnum) + return; + ubifs_add_to_cat(c, &pnode->lprops[i], cat); + } +} + +/** + * replace_cats - add LEB properties of a pnode to LEB category lists and heaps. + * @c: UBIFS file-system description object + * @old_pnode: pnode copied + * @new_pnode: pnode copy + * + * During commit it is sometimes necessary to copy a pnode + * (see dirty_cow_pnode). When that happens, references in + * category lists and heaps must be replaced. This function does that. + */ +static void replace_cats(struct ubifs_info *c, struct ubifs_pnode *old_pnode, + struct ubifs_pnode *new_pnode) +{ + int i; + + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + if (!new_pnode->lprops[i].lnum) + return; + ubifs_replace_cat(c, &old_pnode->lprops[i], + &new_pnode->lprops[i]); + } +} + +/** + * check_lpt_crc - check LPT node crc is correct. + * @c: UBIFS file-system description object + * @buf: buffer containing node + * @len: length of node + * + * This function returns %0 on success and a negative error code on failure. + */ +static int check_lpt_crc(void *buf, int len) +{ + int pos = 0; + uint8_t *addr = buf; + uint16_t crc, calc_crc; + + crc = ubifs_unpack_bits(&addr, &pos, UBIFS_LPT_CRC_BITS); + calc_crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES, + len - UBIFS_LPT_CRC_BYTES); + if (crc != calc_crc) { + ubifs_err("invalid crc in LPT node: crc %hx calc %hx", crc, + calc_crc); + dbg_dump_stack(); + return -EINVAL; + } + return 0; +} + +/** + * check_lpt_type - check LPT node type is correct. + * @c: UBIFS file-system description object + * @addr: address of type bit field is passed and returned updated here + * @pos: position of type bit field is passed and returned updated here + * @type: expected type + * + * This function returns %0 on success and a negative error code on failure. + */ +static int check_lpt_type(uint8_t **addr, int *pos, int type) +{ + int node_type; + + node_type = ubifs_unpack_bits(addr, pos, UBIFS_LPT_TYPE_BITS); + if (node_type != type) { + ubifs_err("invalid type (%d) in LPT node type %d", node_type, + type); + dbg_dump_stack(); + return -EINVAL; + } + return 0; +} + +/** + * unpack_pnode - unpack a pnode. + * @c: UBIFS file-system description object + * @buf: buffer containing packed pnode to unpack + * @pnode: pnode structure to fill + * + * This function returns %0 on success and a negative error code on failure. + */ +static int unpack_pnode(struct ubifs_info *c, void *buf, + struct ubifs_pnode *pnode) +{ + uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES; + int i, pos = 0, err; + + err = check_lpt_type(&addr, &pos, UBIFS_LPT_PNODE); + if (err) + return err; + if (c->big_lpt) + pnode->num = ubifs_unpack_bits(&addr, &pos, c->pcnt_bits); + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + struct ubifs_lprops * const lprops = &pnode->lprops[i]; + + lprops->free = ubifs_unpack_bits(&addr, &pos, c->space_bits); + lprops->free <<= 3; + lprops->dirty = ubifs_unpack_bits(&addr, &pos, c->space_bits); + lprops->dirty <<= 3; + + if (ubifs_unpack_bits(&addr, &pos, 1)) + lprops->flags = LPROPS_INDEX; + else + lprops->flags = 0; + lprops->flags |= ubifs_categorize_lprops(c, lprops); + } + err = check_lpt_crc(buf, c->pnode_sz); + return err; +} + +/** + * unpack_nnode - unpack a nnode. + * @c: UBIFS file-system description object + * @buf: buffer containing packed nnode to unpack + * @nnode: nnode structure to fill + * + * This function returns %0 on success and a negative error code on failure. + */ +static int unpack_nnode(struct ubifs_info *c, void *buf, + struct ubifs_nnode *nnode) +{ + uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES; + int i, pos = 0, err; + + err = check_lpt_type(&addr, &pos, UBIFS_LPT_NNODE); + if (err) + return err; + if (c->big_lpt) + nnode->num = ubifs_unpack_bits(&addr, &pos, c->pcnt_bits); + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + int lnum; + + lnum = ubifs_unpack_bits(&addr, &pos, c->lpt_lnum_bits) + + c->lpt_first; + if (lnum == c->lpt_last + 1) + lnum = 0; + nnode->nbranch[i].lnum = lnum; + nnode->nbranch[i].offs = ubifs_unpack_bits(&addr, &pos, + c->lpt_offs_bits); + } + err = check_lpt_crc(buf, c->nnode_sz); + return err; +} + +/** + * unpack_ltab - unpack the LPT's own lprops table. + * @c: UBIFS file-system description object + * @buf: buffer from which to unpack + * + * This function returns %0 on success and a negative error code on failure. + */ +static int unpack_ltab(struct ubifs_info *c, void *buf) +{ + uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES; + int i, pos = 0, err; + + err = check_lpt_type(&addr, &pos, UBIFS_LPT_LTAB); + if (err) + return err; + for (i = 0; i < c->lpt_lebs; i++) { + int free = ubifs_unpack_bits(&addr, &pos, c->lpt_spc_bits); + int dirty = ubifs_unpack_bits(&addr, &pos, c->lpt_spc_bits); + + if (free < 0 || free > c->leb_size || dirty < 0 || + dirty > c->leb_size || free + dirty > c->leb_size) + return -EINVAL; + + c->ltab[i].free = free; + c->ltab[i].dirty = dirty; + c->ltab[i].tgc = 0; + c->ltab[i].cmt = 0; + } + err = check_lpt_crc(buf, c->ltab_sz); + return err; +} + +/** + * unpack_lsave - unpack the LPT's save table. + * @c: UBIFS file-system description object + * @buf: buffer from which to unpack + * + * This function returns %0 on success and a negative error code on failure. + */ +static int unpack_lsave(struct ubifs_info *c, void *buf) +{ + uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES; + int i, pos = 0, err; + + err = check_lpt_type(&addr, &pos, UBIFS_LPT_LSAVE); + if (err) + return err; + for (i = 0; i < c->lsave_cnt; i++) { + int lnum = ubifs_unpack_bits(&addr, &pos, c->lnum_bits); + + if (lnum < c->main_first || lnum >= c->leb_cnt) + return -EINVAL; + c->lsave[i] = lnum; + } + err = check_lpt_crc(buf, c->lsave_sz); + return err; +} + +/** + * validate_nnode - validate a nnode. + * @c: UBIFS file-system description object + * @nnode: nnode to validate + * @parent: parent nnode (or NULL for the root nnode) + * @iip: index in parent + * + * This function returns %0 on success and a negative error code on failure. + */ +static int validate_nnode(struct ubifs_info *c, struct ubifs_nnode *nnode, + struct ubifs_nnode *parent, int iip) +{ + int i, lvl, max_offs; + + if (c->big_lpt) { + int num = calc_nnode_num_from_parent(c, parent, iip); + + if (nnode->num != num) + return -EINVAL; + } + lvl = parent ? parent->level - 1 : c->lpt_hght; + if (lvl < 1) + return -EINVAL; + if (lvl == 1) + max_offs = c->leb_size - c->pnode_sz; + else + max_offs = c->leb_size - c->nnode_sz; + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + int lnum = nnode->nbranch[i].lnum; + int offs = nnode->nbranch[i].offs; + + if (lnum == 0) { + if (offs != 0) + return -EINVAL; + continue; + } + if (lnum < c->lpt_first || lnum > c->lpt_last) + return -EINVAL; + if (offs < 0 || offs > max_offs) + return -EINVAL; + } + return 0; +} + +/** + * validate_pnode - validate a pnode. + * @c: UBIFS file-system description object + * @pnode: pnode to validate + * @parent: parent nnode + * @iip: index in parent + * + * This function returns %0 on success and a negative error code on failure. + */ +static int validate_pnode(struct ubifs_info *c, struct ubifs_pnode *pnode, + struct ubifs_nnode *parent, int iip) +{ + int i; + + if (c->big_lpt) { + int num = calc_pnode_num_from_parent(c, parent, iip); + + if (pnode->num != num) + return -EINVAL; + } + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + int free = pnode->lprops[i].free; + int dirty = pnode->lprops[i].dirty; + + if (free < 0 || free > c->leb_size || free % c->min_io_size || + (free & 7)) + return -EINVAL; + if (dirty < 0 || dirty > c->leb_size || (dirty & 7)) + return -EINVAL; + if (dirty + free > c->leb_size) + return -EINVAL; + } + return 0; +} + +/** + * set_pnode_lnum - set LEB numbers on a pnode. + * @c: UBIFS file-system description object + * @pnode: pnode to update + * + * This function calculates the LEB numbers for the LEB properties it contains + * based on the pnode number. + */ +static void set_pnode_lnum(struct ubifs_info *c, struct ubifs_pnode * |