/* * 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 of marking the clean 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 "ubifs.h" #include <linux/crc16.h> #include <linux/math64.h> #include <linux/slab.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; if (c->big_lpt) 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; long long 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 */ lebs_needed = div_u64(sz + c->leb_size - 1, c->leb_size); 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; long long 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 */ lebs_needed = div_u64(sz + c->leb_size - 1, c->leb_size); 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 uninitialized_var(val); const int bytes = (nrbits + b + 7) >> 3; ubifs_assert(nrbits > 0); ubifs_assert(nrbits <= 32); ubifs_assert(*pos >= 0); ubifs_assert(*pos < 8); if (b) { switch (bytes) { case 2: val = p[1]; break; case 3: val = p[1] | ((uint32_t)p[2] << 8); break; case 4: val = p[1] | ((uint32_t)p[2] << 8) | ((uint32_t)p[3] << 16); break; case 5: 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 { switch (bytes) { case 1: val = p[0]; break; case 2: val = p[0] | ((uint32_t)p[1] << 8); break; case 3: val = p[0] | ((uint32_t)p[1] << 8) | ((uint32_t)p[2] << 16); break; case 4: val = p[0] | ((uint32_t)p[1] << 8) | ((uint32_t)p[2] << 16) | ((uint32_t)p[3] << 24); break; } } val <<= k; val >>= k; b = nrbits & 7; p += nrbits >> 3; *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(const 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(const 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(const 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; } /** * ubifs_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. */ int ubifs_unpack_nnode(const 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(const 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(const 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(const 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(const 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(const struct ubifs_info *c, struct ubifs_pnode *pnode) { int i, lnum; lnum = (pnode->num << UBIFS_LPT_FANOUT_SHIFT) + c->main_first; for (i = 0; i < UBIFS_LPT_FANOUT; i++) { if (lnum >= c->leb_cnt) return; pnode->lprops[i].lnum = lnum++; } } /** * ubifs_read_nnode - read a nnode from flash and link it to the tree in memory. * @c: UBIFS file-system description object * @parent: parent nnode (or NULL for the root) * @iip: index in parent * * This function returns %0 on success and a negative error code on failure. */ int ubifs_read_nnode(struct ubifs_info *c, struct ubifs_nnode *parent, int iip) { struct ubifs_nbranch *branch = NULL; struct ubifs_nnode *nnode = NULL; void *buf = c->lpt_nod_buf; int err, lnum, offs; if (parent) { branch = &parent->nbranch[iip]; lnum = branch->lnum; offs = branch->offs; } else { lnum = c->lpt_lnum; offs = c->lpt_offs; } nnode = kzalloc(sizeof(struct ubifs_nnode), GFP_NOFS); if (!nnode) { err = -ENOMEM; goto out; } if (lnum == 0) { /* * This nnode was not written which just means that the LEB * properties in the subtree below it describe empty LEBs. We * make the nnode as though we had read it, which in fact means * doing almost nothing. */ if (c->big_lpt) nnode->num = calc_nnode_num_from_parent(c, parent, iip); } else { err = ubi_read(c->ubi, lnum, buf, offs, c->nnode_sz); if (err) goto out; err = ubifs_unpack_nnode(c, buf, nnode); if (err) goto out; } err = validate_nnode(c, nnode, parent, iip); if (err) goto out; if (!c->big_lpt) nnode->num = calc_nnode_num_from_parent(c, parent, iip); if (parent) { branch->nnode = nnode; nnode->level = parent->level - 1; } else { c->nroot = nnode; nnode->level = c->lpt_hght; } nnode->parent = parent; nnode->iip = iip; return 0; out: ubifs_err("error %d reading nnode at %d:%d", err, lnum, offs); kfree(nnode); return err; } /** * read_pnode - read a pnode from flash and link it to the tree in memory. * @c: UBIFS file-system description object * @parent: parent nnode * @iip: index in parent * * This function returns %0 on success and a negative error code on failure. */ static int read_pnode(struct ubifs_info *c, struct ubifs_nnode *parent, int iip) { struct ubifs_nbranch *branch; struct ubifs_pnode *pnode = NULL; void *buf = c->lpt_nod_buf; int err, lnum, offs; branch = &parent->nbranch[iip]; lnum = branch->lnum; offs = branch->offs; pnode = kzalloc(sizeof(struct ubifs_pnode), GFP_NOFS); if (!pnode) { err = -ENOMEM; goto out; } if (lnum == 0) { /* * This pnode was not written which just means that the LEB * properties in it describe empty LEBs. We make the pnode as * though we had read it. */ int i; if (c->big_lpt) pnode->num = calc_pnode_num_from_parent(c, parent, iip); for (i = 0; i < UBIFS_LPT_FANOUT; i++) { struct ubifs_lprops * const lprops = &pnode->lprops[i]; lprops->free = c->leb_size; lprops->flags = ubifs_categorize_lprops(c, lprops); } } else { err = ubi_read(c->ubi, lnum, buf, offs, c->pnode_sz); if (err) goto out; err = unpack_pnode(c, buf, pnode); if (err) goto out; } err = validate_pnode(c, pnode, parent, iip); if (err) goto out; if (!c->big_lpt) pnode->num = calc_pnode_num_from_parent(c, parent, iip); branch->pnode = pnode; pnode->parent = parent; pnode->iip = iip; set_pnode_lnum(c, pnode); c->pnodes_have += 1; return 0; out: ubifs_err("error %d reading pnode at %d:%d", err, lnum, offs); dbg_dump_pnode(c, pnode, parent, iip); dbg_msg("calc num: %d", calc_pnode_num_from_parent(c, parent, iip)); kfree(pnode); return err; } /** * read_ltab - read LPT's own lprops table. * @c: UBIFS file-system description object * * This function returns %0 on success and a negative error code on failure. */ static int read_ltab(struct ubifs_info *c) { int err; void *buf; buf = vmalloc(c->ltab_sz); if (!buf) return -ENOMEM; err = ubi_read(c->ubi, c->ltab_lnum, buf, c->ltab_offs, c->ltab_sz); if (err) goto out; err = unpack_ltab(c, buf); out: vfree(buf); return err; } /** * read_lsave - read LPT's save table. * @c: UBIFS file-system description object * * This function returns %0 on success and a negative error code on failure. */ static int read_lsave(struct ubifs_info *c) { int err, i; void *buf; buf = vmalloc(c->lsave_sz); if (!buf) return -ENOMEM; err = ubi_read(c->ubi, c->lsave_lnum, buf, c->lsave_offs, c->lsave_sz); if (err) goto out; err = unpack_lsave(c, buf); if (err) goto out; for (i = 0; i < c->lsave_cnt; i++) { int lnum = c->lsave[i]; struct ubifs_lprops *lprops; /* * Due to automatic resizing, the values in the lsave table * could be beyond the volume size - just ignore them. */ if (lnum >= c->leb_cnt) continue; lprops = ubifs_lpt_lookup(c, lnum); if (IS_ERR(lprops)) { err = PTR_ERR(lprops); goto out; } } out: vfree(buf); return err; } /** * ubifs_get_nnode - get a nnode. * @c: UBIFS file-system description object * @parent: parent nnode (or NULL for the root) * @iip: index in parent * * This function returns a pointer to the nnode on success or a negative error * code on failure. */ struct ubifs_nnode *ubifs_get_nnode(struct ubifs_info *c, struct ubifs_nnode *parent, int iip) { struct ubifs_nbranch *branch; struct ubifs_nnode *nnode; int err; branch = &parent->nbranch[iip]; nnode = branch->nnode; if (nnode) return nnode; err = ubifs_read_nnode(c, parent, iip); if (err) return ERR_PTR(err); return branch->nnode; } /** * ubifs_get_pnode - get a pnode. * @c: UBIFS file-system description object * @parent: parent nnode * @iip: index in parent * * This function returns a pointer to the pnode on success or a negative error * code on failure. */ struct ubifs_pnode *ubifs_get_pnode(struct ubifs_info *c, struct ubifs_nnode *parent, int iip) { struct ubifs_nbranch *branch; struct ubifs_pnode *pnode; int err; branch = &parent->nbranch[iip]; pnode = branch->pnode; if (pnode) return pnode; err = read_pnode(c, parent, iip); if (err) return ERR_PTR(err); update_cats(c, branch->pnode); return branch->pnode; } /** * ubifs_lpt_lookup - lookup LEB properties in the LPT. * @c: UBIFS file-system description object * @lnum: LEB number to lookup * * This function returns a pointer to the LEB properties on success or a * negative error code on failure. */ struct ubifs_lprops *ubifs_lpt_lookup(struct ubifs_info *c, int lnum) { int err, i, h, iip, shft; struct ubifs_nnode *nnode; struct ubifs_pnode *pnode; if (!c->nroot) { err = ubifs_read_nnode(c, NULL, 0); if (err) return ERR_PTR(err); } nnode = c->nroot; i = lnum - c->main_first; shft = c->lpt_hght * UBIFS_LPT_FANOUT_SHIFT; for (h = 1; h < c->lpt_hght; h++) { iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1)); shft -= UBIFS_LPT_FANOUT_SHIFT; nnode = ubifs_get_nnode(c, nnode, iip); if (IS_ERR(nnode)) return ERR_CAST(nnode); } iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1)); shft -= UBIFS_LPT_FANOUT_SHIFT; pnode = ubifs_get_pnode(c, nnode, iip); if (IS_ERR(pnode)) return ERR_CAST(pnode); iip = (i & (UBIFS_LPT_FANOUT - 1)); dbg_lp("LEB %d, free %d, dirty %d, flags %d", lnum, pnode->lprops[iip].free, pnode->lprops[iip].dirty, pnode->lprops[iip].flags); return &pnode->lprops[iip]; } /** * dirty_cow_nnode - ensure a nnode is not being committed. * @c: UBIFS file-system description object * @nnode: nnode to check * * Returns dirtied nnode on success or negative error code on failure. */ static struct ubifs_nnode *dirty_cow_nnode(struct ubifs_info *c, struct ubifs_nnode *nnode) { struct ubifs_nnode *n; int i; if (!test_bit(COW_CNODE, &nnode->flags)) { /* nnode is not being committed */ if (!test_and_set_bit(DIRTY_CNODE, &nnode->flags)) { c->dirty_nn_cnt += 1; ubifs_add_nnode_dirt(c, nnode); } return nnode; } /* nnode is being committed, so copy it */ n = kmalloc(sizeof(struct ubifs_nnode), GFP_NOFS); if (unlikely(!n)) return ERR_PTR(-ENOMEM); memcpy(n, nnode, sizeof(struct ubifs_nnode)); n->cnext = NULL; __set_bit(DIRTY_CNODE, &n->flags); __clear_bit(COW_CNODE, &n->flags); /* The children now have new parent */ for (i = 0; i < UBIFS_LPT_FANOUT; i++) { struct ubifs_nbranch *branch = &n->nbranch[i]; if (branch->cnode) branch->cnode->parent = n; } ubifs_assert(!test_bit(OBSOLETE_CNODE, &nnode->flags)); __set_bit(OBSOLETE_CNODE, &nnode->flags); c->dirty_nn_cnt += 1; ubifs_add_nnode_dirt(c, nnode); if (nnode->parent) nnode->parent->nbranch[n->iip].nnode = n; else c->nroot = n; return n; } /** * dirty_cow_pnode - ensure a pnode is not being committed. * @c: UBIFS file-system description object * @pnode: pnode to check * * Returns dirtied pnode on success or negative error code on failure. */ static struct ubifs_pnode *dirty_cow_pnode(struct ubifs_info *c, struct ubifs_pnode *pnode) { struct ubifs_pnode *p; if (!test_bit(COW_CNODE, &pnode->flags)) { /* pnode is not being committed */ if (!test_and_set_bit(DIRTY_CNODE, &pnode->flags)) { c->dirty_pn_cnt += 1; add_pnode_dirt(c, pnode); } return pnode; } /* pnode is being committed, so copy it */ p = kmalloc(sizeof(struct ubifs_pnode), GFP_NOFS); if (unlikely(!p)) return ERR_PTR(-ENOMEM); memcpy(p, pnode, sizeof(struct ubifs_pnode)); p->cnext = NULL; __set_bit(DIRTY_CNODE, &p->flags); __clear_bit(COW_CNODE, &p->flags); replace_cats(c, pnode, p); ubifs_assert(!test_bit(OBSOLETE_CNODE, &pnode->flags)); __set_bit(OBSOLETE_CNODE, &pnode->flags); c->dirty_pn_cnt += 1; add_pnode_dirt(c, pnode); pnode->parent->nbranch[p->iip].pnode = p; return p; } /** * ubifs_lpt_lookup_dirty - lookup LEB properties in the LPT. * @c: UBIFS file-system description object * @lnum: LEB number to lookup * * This function returns a pointer to the LEB properties on success or a * negative error code on failure. */ struct ubifs_lprops *ubifs_lpt_lookup_dirty(struct ubifs_info *c, int lnum) { int err, i, h, iip, shft; struct ubifs_nnode *nnode; struct ubifs_pnode *pnode; if (!c->nroot) { err = ubifs_read_nnode(c, NULL, 0); if (err) return ERR_PTR(err); } nnode = c->nroot; nnode = dirty_cow_nnode(c, nnode); if (IS_ERR(nnode)) return ERR_CAST(nnode); i = lnum - c->main_first; shft = c->lpt_hght * UBIFS_LPT_FANOUT_SHIFT; for (h = 1; h < c->lpt_hght; h++) { iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1)); shft -= UBIFS_LPT_FANOUT_SHIFT; nnode = ubifs_get_nnode(c, nnode, iip); if (IS_ERR(nnode)) return ERR_CAST(nnode); nnode = dirty_cow_nnode(c, nnode); if (IS_ERR(nnode)) return ERR_CAST(nnode); } iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1)); shft -= UBIFS_LPT_FANOUT_SHIFT; pnode = ubifs_get_pnode(c, nnode, iip); if (IS_ERR(pnode)) return ERR_CAST(pnode); pnode = dirty_cow_pnode(c, pnode); if (IS_ERR(pnode)) return ERR_CAST(pnode); iip = (i & (UBIFS_LPT_FANOUT - 1)); dbg_lp("LEB %d, free %d, dirty %d, flags %d", lnum, pnode->lprops[iip].free, pnode->lprops[iip].dirty, pnode->lprops[iip].flags); ubifs_assert(test_bit(DIRTY_CNODE, &pnode->flags)); return &pnode->lprops[iip]; } /** * lpt_init_rd - initialize the LPT for reading. * @c: UBIFS file-system description object * * This function returns %0 on success and a negative error code on failure. */ static int lpt_init_rd(struct ubifs_info *c) { int err, i; c->ltab = vmalloc(sizeof(struct ubifs_lpt_lprops) * c->lpt_lebs); if (!c->ltab) return -ENOMEM; i = max_t(int, c->nnode_sz, c->pnode_sz); c->lpt_nod_buf = kmalloc(i, GFP_KERNEL); if (!c->lpt_nod_buf) return -ENOMEM; for (i = 0; i < LPROPS_HEAP_CNT; i++) { c->lpt_heap[i].arr = kmalloc(sizeof(void *) * LPT_HEAP_SZ, GFP_KERNEL); if (!c->lpt_heap[i].arr) return -ENOMEM; c->lpt_heap[i].cnt = 0; c->lpt_heap[i].max_cnt = LPT_HEAP_SZ; } c->dirty_idx.arr = kmalloc(sizeof(void *) * LPT_HEAP_SZ, GFP_KERNEL); if (!c->dirty_idx.arr) return -ENOMEM; c->dirty_idx.cnt = 0; c->dirty_idx.max_cnt = LPT_HEAP_SZ; err = read_ltab(c); if (err) return err; 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); return 0; } /** * lpt_init_wr - initialize the LPT for writing. * @c: UBIFS file-system description object * * 'lpt_init_rd()' must have been called already. * * This function returns %0 on success and a negative error code on failure. */ static int lpt_init_wr(struct ubifs_info *c) { int err, i; c->ltab_cmt = vmalloc(sizeof(struct ubifs_lpt_lprops) * c->lpt_lebs); if (!c->ltab_cmt) return -ENOMEM; c->lpt_buf = vmalloc(c->leb_size); if (!c->lpt_buf) return -ENOMEM; if (c->big_lpt) { c->lsave = kmalloc(sizeof(int) * c->lsave_cnt, GFP_NOFS); if (!c->lsave) return -ENOMEM; err = read_lsave(c); if (err) return err; } for (i = 0; i < c->lpt_lebs; i++) if (c->ltab[i].free == c->leb_size) { err = ubifs_leb_unmap(c, i + c->lpt_first); if (err) return err; } return 0; } /** * ubifs_lpt_init - initialize the LPT. * @c: UBIFS file-system description object * @rd: whether to initialize lpt for reading * @wr: whether to initialize lpt for writing * * For mounting 'rw', @rd and @wr are both true. For mounting 'ro', @rd is true * and @wr is false. For mounting from 'ro' to 'rw', @rd is false and @wr is * true. * * This function returns %0 on success and a negative error code on failure. */ int ubifs_lpt_init(struct ubifs_info *c, int rd, int wr) { int err; if (rd) { err = lpt_init_rd(c); if (err) return err; } if (wr) { err = lpt_init_wr(c); if (err) return err; } return 0; } /** * struct lpt_scan_node - somewhere to put nodes while we scan LPT. * @nnode: where to keep a nnode * @pnode: where to keep a pnode * @cnode: where to keep a cnode * @in_tree: is the node in the tree in memory * @ptr.nnode: pointer to the nnode (if it is an nnode) which may be here or in * the tree * @ptr.pnode: ditto for pnode * @ptr.cnode: ditto for cnode */ struct lpt_scan_node { union { struct ubifs_nnode nnode; struct ubifs_pnode pnode; struct ubifs_cnode cnode; }; int in_tree; union { struct ubifs_nnode *nnode; struct ubifs_pnode *pnode; struct ubifs_cnode *cnode; } ptr; }; /** * scan_get_nnode - for the scan, get a nnode from either the tree or flash. * @c: the UBIFS file-system description object * @path: where to put the nnode * @parent: parent of the nnode * @iip: index in parent of the nnode * * This function returns a pointer to the nnode on success or a negative error * code on failure. */ static struct ubifs_nnode *scan_get_nnode(struct ubifs_info *c, struct lpt_scan_node *path, struct ubifs_nnode *parent, int iip) { struct ubifs_nbranch *branch; struct ubifs_nnode *nnode; void *buf = c->lpt_nod_buf; int err; branch = &parent->nbranch[iip]; nnode = branch->nnode; if (nnode) { path->in_tree = 1; path->ptr.nnode = nnode; return nnode; } nnode = &path->nnode; path->in_tree = 0; path->ptr.nnode = nnode; memset(nnode, 0, sizeof(struct ubifs_nnode)); if (branch->lnum == 0) { /* * This nnode was not written which just means that the LEB * properties in the subtree below it describe empty LEBs. We * make the nnode as though we had read it, which in fact means * doing almost nothing. */ if (c->big_lpt) nnode->num = calc_nnode_num_from_parent(c, parent, iip); } else { err = ubi_read(c->ubi, branch->lnum, buf, branch->offs, c->nnode_sz); if (err) return ERR_PTR(err); err = ubifs_unpack_nnode(c, buf, nnode); if (err) return ERR_PTR(err); } err = validate_nnode(c, nnode, parent, iip); if (err) return ERR_PTR(err); if (!c->big_lpt) nnode->num = calc_nnode_num_from_parent(c, parent, iip); nnode->level = parent->level - 1; nnode->parent = parent; nnode->iip = iip; return nnode; } /** * scan_get_pnode - for the scan, get a pnode from either the tree or flash. * @c: the UBIFS file-system description object * @path: where to put the pnode * @parent: parent of the pnode * @iip: index in parent of the pnode * * This function returns a pointer to the pnode on success or a negative error * code on failure. */ static struct ubifs_pnode *scan_get_pnode(struct ubifs_info *c, struct lpt_scan_node *path, struct ubifs_nnode *parent, int iip) { struct ubifs_nbranch *branch; struct ubifs_pnode *pnode; void *buf = c->lpt_nod_buf; int err; branch = &parent->nbranch[iip]; pnode = branch->pnode; if (pnode) { path->in_tree = 1; path->ptr.pnode = pnode; return pnode; } pnode = &path->pnode; path->in_tree = 0; path->ptr.pnode = pnode; memset(pnode, 0, sizeof(struct ubifs_pnode)); if (branch->lnum == 0) { /* * This pnode was not written which just means that the LEB * properties in it describe empty LEBs. We make the pnode as * though we had read it. */ int i; if (c->big_lpt) pnode->num = calc_pnode_num_from_parent(c, parent, iip); for (i = 0; i < UBIFS_LPT_FANOUT; i++) { struct ubifs_lprops * const lprops = &pnode->lprops[i]; lprops->free = c->leb_size; lprops->flags = ubifs_categorize_lprops(c, lprops); } } else { ubifs_assert(branch->lnum >= c->lpt_first && branch->lnum <= c->lpt_last); ubifs_assert(branch->offs >= 0 && branch->offs < c->leb_size); err = ubi_read(c->ubi, branch->lnum, buf, branch->offs, c->pnode_sz); if (err) return ERR_PTR(err); err = unpack_pnode(c, buf, pnode); if (err) return ERR_PTR(err); } err = validate_pnode(c, pnode, parent, iip); if (err) return ERR_PTR(err); if (!c->big_lpt) pnode->num = calc_pnode_num_from_parent(c, parent, iip); pnode->parent = parent; pnode->iip = iip; set_pnode_lnum(c, pnode); return pnode; } /** * ubifs_lpt_scan_nolock - scan the LPT. * @c: the UBIFS file-system description object * @start_lnum: LEB number from which to start scanning * @end_lnum: LEB number at which to stop scanning * @scan_cb: callback function called for each lprops * @data: data to be passed to the callback function * * This function returns %0 on success and a negative error code on failure. */ int ubifs_lpt_scan_nolock(struct ubifs_info *c, int start_lnum, int end_lnum, ubifs_lpt_scan_callback scan_cb, void *data) { int err = 0, i, h, iip, shft; struct ubifs_nnode *nnode; struct ubifs_pnode *pnode; struct lpt_scan_node *path; if (start_lnum == -1) { start_lnum = end_lnum + 1; if (start_lnum >= c->leb_cnt) start_lnum = c->main_first; } ubifs_assert(start_lnum >= c->main_first && start_lnum < c->leb_cnt); ubifs_assert(end_lnum >= c->main_first && end_lnum < c->leb_cnt); if (!c->nroot) { err = ubifs_read_nnode(c, NULL, 0); if (err) return err; } path = kmalloc(sizeof(struct lpt_scan_node) * (c->lpt_hght + 1), GFP_NOFS); if (!path) return -ENOMEM; path[0].ptr.nnode = c->nroot; path[0].in_tree = 1; again: /* Descend to the pnode containing start_lnum */ nnode = c->nroot; i = start_lnum - c->main_first; shft = c->lpt_hght * UBIFS_LPT_FANOUT_SHIFT; for (h = 1; h < c->lpt_hght; h++) { iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1)); shft -= UBIFS_LPT_FANOUT_SHIFT; nnode = scan_get_nnode(c, path + h, nnode, iip); if (IS_ERR(nnode)) { err = PTR_ERR(nnode); goto out; } } iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1)); shft -= UBIFS_LPT_FANOUT_SHIFT; pnode = scan_get_pnode(c, path + h, nnode, iip); if (IS_ERR(pnode)) { err = PTR_ERR(pnode); goto out; } iip = (i & (UBIFS_LPT_FANOUT - 1)); /* Loop for each lprops */ while (1) { struct ubifs_lprops *lprops = &pnode->lprops[iip]; int ret, lnum = lprops->lnum; ret = scan_cb(c, lprops, path[h].in_tree, data); if (ret < 0) { err = ret; goto out; } if (ret & LPT_SCAN_ADD) { /* Add all the nodes in path to the tree in memory */ for (h = 1; h < c->lpt_hght; h++) { const size_t sz = sizeof(struct ubifs_nnode); struct ubifs_nnode *parent; if (path[h].in_tree) continue; nnode = kmalloc(sz, GFP_NOFS); if (!nnode) { err = -ENOMEM; goto out; } memcpy(nnode, &path[h].nnode, sz); parent = nnode->parent; parent->nbranch[nnode->iip].nnode = nnode; path[h].ptr.nnode = nnode; path[h].in_tree = 1; path[h + 1].cnode.parent = nnode; } if (path[h].in_tree) ubifs_ensure_cat(c, lprops); else { const size_t sz = sizeof(struct ubifs_pnode); struct ubifs_nnode *parent; pnode = kmalloc(sz, GFP_NOFS); if (!pnode) { err = -ENOMEM; goto out; } memcpy(pnode, &path[h].pnode, sz); parent = pnode->parent; parent->nbranch[pnode->iip].pnode = pnode; path[h].ptr.pnode = pnode; path[h].in_tree = 1; update_cats(c, pnode); c->pnodes_have += 1; } err = dbg_check_lpt_nodes(c, (struct ubifs_cnode *) c->nroot, 0, 0); if (err) goto out; err = dbg_check_cats(c); if (err) goto out; } if (ret & LPT_SCAN_STOP) { err = 0; break; } /* Get the next lprops */ if (lnum == end_lnum) { /* * We got to the end without finding what we were * looking for */ err = -ENOSPC; goto out; } if (lnum + 1 >= c->leb_cnt) { /* Wrap-around to the beginning */ start_lnum = c->main_first; goto again; } if (iip + 1 < UBIFS_LPT_FANOUT) { /* Next lprops is in the same pnode */ iip += 1; continue; } /* We need to get the next pnode. Go up until we can go right */ iip = pnode->iip; while (1) { h -= 1; ubifs_assert(h >= 0); nnode = path[h].ptr.nnode; if (iip + 1 < UBIFS_LPT_FANOUT) break; iip = nnode->iip; } /* Go right */ iip += 1; /* Descend to the pnode */ h += 1; for (; h < c->lpt_hght; h++) { nnode = scan_get_nnode(c, path + h, nnode, iip); if (IS_ERR(nnode)) { err = PTR_ERR(nnode); goto out; } iip = 0; } pnode = scan_get_pnode(c, path + h, nnode, iip); if (IS_ERR(pnode)) { err = PTR_ERR(pnode); goto out; } iip = 0; } out: kfree(path); return err; } #ifdef CONFIG_UBIFS_FS_DEBUG /** * dbg_chk_pnode - check a pnode. * @c: the UBIFS file-system description object * @pnode: pnode to check * @col: pnode column * * This function returns %0 on success and a negative error code on failure. */ static int dbg_chk_pnode(struct ubifs_info *c, struct ubifs_pnode *pnode, int col) { int i; if (pnode->num != col) { dbg_err("pnode num %d expected %d parent num %d iip %d", pnode->num, col, pnode->parent->num, pnode->iip); return -EINVAL; } for (i = 0; i < UBIFS_LPT_FANOUT; i++) { struct ubifs_lprops *lp, *lprops = &pnode->lprops[i]; int lnum = (pnode->num << UBIFS_LPT_FANOUT_SHIFT) + i + c->main_first; int found, cat = lprops->flags & LPROPS_CAT_MASK; struct ubifs_lpt_heap *heap; struct list_head *list = NULL; if (lnum >= c->leb_cnt) continue; if (lprops->lnum != lnum) { dbg_err("bad LEB number %d expected %d", lprops->lnum, lnum); return -EINVAL; } if (lprops->flags & LPROPS_TAKEN) { if (cat != LPROPS_UNCAT) { dbg_err("LEB %d taken but not uncat %d", lprops->lnum, cat); return -EINVAL; } continue; } if (lprops->flags & LPROPS_INDEX) { switch (cat) { case LPROPS_UNCAT: case LPROPS_DIRTY_IDX: case LPROPS_FRDI_IDX: break; default: dbg_err("LEB %d index but cat %d", lprops->lnum, cat); return -EINVAL; } } else { switch (cat) { case LPROPS_UNCAT: case LPROPS_DIRTY: case LPROPS_FREE: case LPROPS_EMPTY: case LPROPS_FREEABLE: break; default: dbg_err("LEB %d not index but cat %d", lprops->lnum, cat); return -EINVAL; } } switch (cat) { case LPROPS_UNCAT: list = &c->uncat_list; break; case LPROPS_EMPTY: list = &c->empty_list; break; case LPROPS_FREEABLE: list = &c->freeable_list; break; case LPROPS_FRDI_IDX: list = &c->frdi_idx_list; break; } found = 0; switch (cat) { case LPROPS_DIRTY: case LPROPS_DIRTY_IDX: case LPROPS_FREE: heap = &c->lpt_heap[cat - 1]; if (lprops->hpos < heap->cnt && heap->arr[lprops->hpos] == lprops) found = 1; break; case LPROPS_UNCAT: case LPROPS_EMPTY: case LPROPS_FREEABLE: case LPROPS_FRDI_IDX: list_for_each_entry(lp, list, list) if (lprops == lp) { found = 1; break; } break; } if (!found) { dbg_err("LEB %d cat %d not found in cat heap/list", lprops->lnum, cat); return -EINVAL; } switch (cat) { case LPROPS_EMPTY: if (lprops->free != c->leb_size) { dbg_err("LEB %d cat %d free %d dirty %d", lprops->lnum, cat, lprops->free, lprops->dirty); return -EINVAL; } case LPROPS_FREEABLE: case LPROPS_FRDI_IDX: if (lprops->free + lprops->dirty != c->leb_size) { dbg_err("LEB %d cat %d free %d dirty %d", lprops->lnum, cat, lprops->free, lprops->dirty); return -EINVAL; } } } return 0; } /** * dbg_check_lpt_nodes - check nnodes and pnodes. * @c: the UBIFS file-system description object * @cnode: next cnode (nnode or pnode) to check * @row: row of cnode (root is zero) * @col: column of cnode (leftmost is zero) * * This function returns %0 on success and a negative error code on failure. */ int dbg_check_lpt_nodes(struct ubifs_info *c, struct ubifs_cnode *cnode, int row, int col) { struct ubifs_nnode *nnode, *nn; struct ubifs_cnode *cn; int num, iip = 0, err; if (!(ubifs_chk_flags & UBIFS_CHK_LPROPS)) return 0; while (cnode) { ubifs_assert(row >= 0); nnode = cnode->parent; if (cnode->level) { /* cnode is a nnode */ num = calc_nnode_num(row, col); if (cnode->num != num) { dbg_err("nnode num %d expected %d " "parent num %d iip %d", cnode->num, num, (nnode ? nnode->num : 0), cnode->iip); return -EINVAL; } nn = (struct ubifs_nnode *)cnode; while (iip < UBIFS_LPT_FANOUT) { cn = nn->nbranch[iip].cnode; if (cn) { /* Go down */ row += 1; col <<= UBIFS_LPT_FANOUT_SHIFT; col += iip; iip = 0; cnode = cn; break; } /* Go right */ iip += 1; } if (iip < UBIFS_LPT_FANOUT) continue; } else { struct ubifs_pnode *pnode; /* cnode is a pnode */ pnode = (struct ubifs_pnode *)cnode; err = dbg_chk_pnode(c, pnode, col); if (err) return err; } /* Go up and to the right */ row -= 1; col >>= UBIFS_LPT_FANOUT_SHIFT; iip = cnode->iip + 1; cnode = (struct ubifs_cnode *)nnode; } return 0; } #endif /* CONFIG_UBIFS_FS_DEBUG */