/* * 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 commit-related functionality of the LEB properties * subsystem. */ #include #include #include #include "ubifs.h" #ifdef CONFIG_UBIFS_FS_DEBUG static int dbg_populate_lsave(struct ubifs_info *c); #else #define dbg_populate_lsave(c) 0 #endif /** * first_dirty_cnode - find first dirty cnode. * @c: UBIFS file-system description object * @nnode: nnode at which to start * * This function returns the first dirty cnode or %NULL if there is not one. */ static struct ubifs_cnode *first_dirty_cnode(struct ubifs_nnode *nnode) { ubifs_assert(nnode); while (1) { int i, cont = 0; for (i = 0; i < UBIFS_LPT_FANOUT; i++) { struct ubifs_cnode *cnode; cnode = nnode->nbranch[i].cnode; if (cnode && test_bit(DIRTY_CNODE, &cnode->flags)) { if (cnode->level == 0) return cnode; nnode = (struct ubifs_nnode *)cnode; cont = 1; break; } } if (!cont) return (struct ubifs_cnode *)nnode; } } /** * next_dirty_cnode - find next dirty cnode. * @cnode: cnode from which to begin searching * * This function returns the next dirty cnode or %NULL if there is not one. */ static struct ubifs_cnode *next_dirty_cnode(struct ubifs_cnode *cnode) { struct ubifs_nnode *nnode; int i; ubifs_assert(cnode); nnode = cnode->parent; if (!nnode) return NULL; for (i = cnode->iip + 1; i < UBIFS_LPT_FANOUT; i++) { cnode = nnode->nbranch[i].cnode; if (cnode && test_bit(DIRTY_CNODE, &cnode->flags)) { if (cnode->level == 0) return cnode; /* cnode is a pnode */ /* cnode is a nnode */ return first_dirty_cnode((struct ubifs_nnode *)cnode); } } return (struct ubifs_cnode *)nnode; } /** * get_cnodes_to_commit - create list of dirty cnodes to commit. * @c: UBIFS file-system description object * * This function returns the number of cnodes to commit. */ static int get_cnodes_to_commit(struct ubifs_info *c) { struct ubifs_cnode *cnode, *cnext; int cnt = 0; if (!c->nroot) return 0; if (!test_bit(DIRTY_CNODE, &c->nroot->flags)) return 0; c->lpt_cnext = first_dirty_cnode(c->nroot); cnode = c->lpt_cnext; if (!cnode) return 0; cnt += 1; while (1) { ubifs_assert(!test_bit(COW_CNODE, &cnode->flags)); __set_bit(COW_CNODE, &cnode->flags); cnext = next_dirty_cnode(cnode); if (!cnext) { cnode->cnext = c->lpt_cnext; break; } cnode->cnext = cnext; cnode = cnext; cnt += 1; } dbg_cmt("committing %d cnodes", cnt); dbg_lp("committing %d cnodes", cnt); ubifs_assert(cnt == c->dirty_nn_cnt + c->dirty_pn_cnt); return cnt; } /** * upd_ltab - update LPT LEB properties. * @c: UBIFS file-system description object * @lnum: LEB number * @free: amount of free space * @dirty: amount of dirty space to add */ static void upd_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; } /** * alloc_lpt_leb - allocate an LPT LEB that is empty. * @c: UBIFS file-system description object * @lnum: LEB number is passed and returned here * * This function finds the next empty LEB in the ltab starting from @lnum. If a * an empty LEB is found it is returned in @lnum and the function returns %0. * Otherwise the function returns -ENOSPC. Note however, that LPT is designed * never to run out of space. */ static int alloc_lpt_leb(struct ubifs_info *c, int *lnum) { int i, n; n = *lnum - c->lpt_first + 1; for (i = n; i < c->lpt_lebs; i++) { if (c->ltab[i].tgc || c->ltab[i].cmt) continue; if (c->ltab[i].free == c->leb_size) { c->ltab[i].cmt = 1; *lnum = i + c->lpt_first; return 0; } } for (i = 0; i < n; i++) { if (c->ltab[i].tgc || c->ltab[i].cmt) continue; if (c->ltab[i].free == c->leb_size) { c->ltab[i].cmt = 1; *lnum = i + c->lpt_first; return 0; } } return -ENOSPC; } /** * layout_cnodes - layout cnodes for commit. * @c: UBIFS file-system description object * * This function returns %0 on success and a negative error code on failure. */ static int layout_cnodes(struct ubifs_info *c) { int lnum, offs, len, alen, done_lsave, done_ltab, err; struct ubifs_cnode *cnode; err = dbg_chk_lpt_sz(c, 0, 0); if (err) return err; cnode = c->lpt_cnext; if (!cnode) return 0; lnum = c->nhead_lnum; offs = c->nhead_offs; /* Try to place lsave and ltab nicely */ done_lsave = !c->big_lpt; done_ltab = 0; if (!done_lsave && offs + c->lsave_sz <= c->leb_size) { done_lsave = 1; c->lsave_lnum = lnum; c->lsave_offs = offs; offs += c->lsave_sz; dbg_chk_lpt_sz(c, 1, c->lsave_sz); } if (offs + c->ltab_sz <= c->leb_size) { done_ltab = 1; c->ltab_lnum = lnum; c->ltab_offs = offs; offs += c->ltab_sz; dbg_chk_lpt_sz(c, 1, c->ltab_sz); } do { if (cnode->level) { len = c->nnode_sz; c->dirty_nn_cnt -= 1; } else { len = c->pnode_sz; c->dirty_pn_cnt -= 1; } while (offs + len > c->leb_size) { alen = ALIGN(offs, c->min_io_size); upd_ltab(c, lnum, c->leb_size - alen, alen - offs); dbg_chk_lpt_sz(c, 2, c->leb_size - offs); err = alloc_lpt_leb(c, &lnum); if (err) goto no_space; offs = 0; ubifs_assert(lnum >= c->lpt_first && lnum <= c->lpt_last); /* Try to place lsave and ltab nicely */ if (!done_lsave) { done_lsave = 1; c->lsave_lnum = lnum; c->lsave_offs = offs; offs += c->lsave_sz; dbg_chk_lpt_sz(c, 1, c->lsave_sz); continue; } if (!done_ltab) { done_ltab = 1; c->ltab_lnum = lnum; c->ltab_offs = offs; offs += c->ltab_sz; dbg_chk_lpt_sz(c, 1, c->ltab_sz); continue; } break; } if (cnode->parent) { cnode->parent->nbranch[cnode->iip].lnum = lnum; cnode->parent->nbranch[cnode->iip].offs = offs; } else { c->lpt_lnum = lnum; c->lpt_offs = offs; } offs += len; dbg_chk_lpt_sz(c, 1, len); cnode = cnode->cnext; } while (cnode && cnode != c->lpt_cnext); /* Make sure to place LPT's save table */ if (!done_lsave) { if (offs + c->lsave_sz > c->leb_size) { alen = ALIGN(offs, c->min_io_size); upd_ltab(c, lnum, c->leb_size - alen, alen - offs); dbg_chk_lpt_sz(c, 2, c->leb_size - offs); err = alloc_lpt_leb(c, &lnum); if (err) goto no_space; offs = 0; ubifs_assert(lnum >= c->lpt_first && lnum <= c->lpt_last); } done_lsave = 1; c->lsave_lnum = lnum; c->lsave_offs = offs; offs += c->lsave_sz; dbg_chk_lpt_sz(c, 1, c->lsave_sz); } /* Make sure to place LPT's own lprops table */ if (!done_ltab) { if (offs + c->ltab_sz > c->leb_size) { alen = ALIGN(offs, c->min_io_size); upd_ltab(c, lnum, c->leb_size - alen, alen - offs); dbg_chk_lpt_sz(c, 2, c->leb_size - offs); err = alloc_lpt_leb(c, &lnum); if (err) goto no_space; offs = 0; ubifs_assert(lnum >= c->lpt_first && lnum <= c->lpt_last); } done_ltab = 1; c->ltab_lnum = lnum; c->ltab_offs = offs; offs += c->ltab_sz; dbg_chk_lpt_sz(c, 1, c->ltab_sz); } alen = ALIGN(offs, c->min_io_size); upd_ltab(c, lnum, c->leb_size - alen, alen - offs); dbg_chk_lpt_sz(c, 4, alen - offs); err = dbg_chk_lpt_sz(c, 3, alen); if (err) return err; return 0; no_space: ubifs_err("LPT out of space"); dbg_err("LPT out of space at LEB %d:%d needing %d, done_ltab %d, " "done_lsave %d", lnum, offs, len, done_ltab, done_lsave); dbg_dump_lpt_info(c); dbg_dump_lpt_lebs(c); dump_stack(); return err; } /** * realloc_lpt_leb - allocate an LPT LEB that is empty. * @c: UBIFS file-system description object * @lnum: LEB number is passed and returned here * * This function duplicates exactly the results of the function alloc_lpt_leb. * It is used during end commit to reallocate the same LEB numbers that were * allocated by alloc_lpt_leb during start commit. * * This function finds the next LEB that was allocated by the alloc_lpt_leb * function starting from @lnum. If a LEB is found it is returned in @lnum and * the function returns %0. Otherwise the function returns -ENOSPC. * Note however, that LPT is designed never to run out of space. */ static int realloc_lpt_leb(struct ubifs_info *c, int *lnum) { int i, n; n = *lnum - c->lpt_first + 1; for (i = n; i < c->lpt_lebs; i++) if (c->ltab[i].cmt) { c->ltab[i].cmt = 0; *lnum = i + c->lpt_first; return 0; } for (i = 0; i < n; i++) if (c->ltab[i].cmt) { c->ltab[i].cmt = 0; *lnum = i + c->lpt_first; return 0; } return -ENOSPC; } /** * write_cnodes - write cnodes for commit. * @c: UBIFS file-system description object * * This function returns %0 on success and a negative error code on failure. */ static int write_cnodes(struct ubifs_info *c) { int lnum, offs, len, from, err, wlen, alen, done_ltab, done_lsave; struct ubifs_cnode *cnode; void *buf = c->lpt_buf; cnode = c->lpt_cnext; if (!cnode) return 0; lnum = c->nhead_lnum; offs = c->nhead_offs; from = offs; /* Ensure empty LEB is unmapped */ if (offs == 0) { err = ubifs_leb_unmap(c, lnum); if (err) return err; } /* Try to place lsave and ltab nicely */ done_lsave = !c->big_lpt; done_ltab = 0; if (!done_lsave && offs + c->lsave_sz <= c->leb_size) { done_lsave = 1; ubifs_pack_lsave(c, buf + offs, c->lsave); offs += c->lsave_sz; dbg_chk_lpt_sz(c, 1, c->lsave_sz); } if (offs + c->ltab_sz <= c->leb_size) { done_ltab = 1; ubifs_pack_ltab(c, buf + offs, c->ltab_cmt); offs += c->ltab_sz; dbg_chk_lpt_sz(c, 1, c->ltab_sz); } /* Loop for each cnode */ do { if (cnode->level) len = c->nnode_sz; else len = c->pnode_sz; while (offs + len > c->leb_size) { wlen = offs - from; if (wlen) { alen = ALIGN(wlen, c->min_io_size); memset(buf + offs, 0xff, alen - wlen); err = ubifs_leb_write(c, lnum, buf + from, from, alen, UBI_SHORTTERM); if (err) return err; } dbg_chk_lpt_sz(c, 2, c->leb_size - offs); err = realloc_lpt_leb(c, &lnum); if (err) goto no_space; offs = from = 0; ubifs_assert(lnum >= c->lpt_first && lnum <= c->lpt_last); err = ubifs_leb_unmap(c, lnum); if (err) return err; /* Try to place lsave and ltab nicely */ if (!done_lsave) { done_lsave = 1; ubifs_pack_lsave(c, buf + offs, c->lsave); offs += c->lsave_sz; dbg_chk_lpt_sz(c, 1, c->lsave_sz); continue; } if (!done_ltab) { done_ltab = 1; ubifs_pack_ltab(c, buf + offs, c->ltab_cmt); offs += c->ltab_sz; dbg_chk_lpt_sz(c, 1, c->ltab_sz); continue; } break; } if (cnode->level) ubifs_pack_nnode(c, buf + offs, (struct ubifs_nnode *)cnode); else ubifs_pack_pnode(c, buf + offs, (struct ubifs_pnode *)cnode); /* * The reason for the barriers is the same as in case of TNC. * See comment in 'write_index()'. 'dirty_cow_nnode()' and * 'dirty_cow_pnode()' are the functions for which this is * important. */ clear_bit(DIRTY_CNODE, &cnode->flags); smp_mb__before_clear_bit(); clear_bit(COW_CNODE, &cnode->flags); smp_mb__after_clear_bit(); offs += len; dbg_chk_lpt_sz(c, 1, len); cnode = cnode->cnext; } while (cnode && cnode != c->lpt_cnext); /* Make sure to place LPT's save table */ if (!done_lsave) { if (offs + c->lsave_sz > c->leb_size) { wlen = offs - from; alen = ALIGN(wlen, c->min_io_size); memset(buf + offs, 0xff, alen - wlen); err = ubifs_leb_write(c, lnum, buf + from, from, alen, UBI_SHORTTERM); if (err) return err; dbg_chk_lpt_sz(c, 2, c->leb_size - offs); err = realloc_lpt_leb(c, &lnum); if (err) goto no_space; offs = from = 0; ubifs_assert(lnum >= c->lpt_first && lnum <= c->lpt_last); err = ubifs_leb_unmap(c, lnum); if (err) return err; } done_lsave = 1; ubifs_pack_lsave(c, buf + offs, c->lsave); offs += c->lsave_sz; dbg_chk_lpt_sz(c, 1, c->lsave_sz); } /* Make sure to place LPT's own lprops table */ if (!done_ltab) { if (offs + c->ltab_sz > c->leb_size) { wlen = offs - from; alen = ALIGN(wlen, c->min_io_size); memset(buf + offs, 0xff, alen - wlen); err = ubifs_leb_write(c, lnum, buf + from, from, alen, UBI_SHORTTERM); if (err) return err; dbg_chk_lpt_sz(c, 2, c->leb_size - offs); err = realloc_lpt_leb(c, &lnum); if (err) goto no_space; offs = from = 0; ubifs_assert(lnum >= c->lpt_first && lnum <= c->lpt_last); err = ubifs_leb_unmap(c, lnum); if (err) return err; } done_ltab = 1; ubifs_pack_ltab(c, buf + offs, c->ltab_cmt); offs += c->ltab_sz; dbg_chk_lpt_sz(c, 1, c->ltab_sz); } /* Write remaining data in buffer */ wlen = offs - from; alen = ALIGN(wlen, c->min_io_size); memset(buf + offs, 0xff, alen - wlen); err = ubifs_leb_write(c, lnum, buf + from, from, alen, UBI_SHORTTERM); if (err) return err; dbg_chk_lpt_sz(c, 4, alen - wlen); err = dbg_chk_lpt_sz(c, 3, ALIGN(offs, c->min_io_size)); if (err) return err; c->nhead_lnum = lnum; c->nhead_offs = ALIGN(offs, c->min_io_size); 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; no_space: ubifs_err("LPT out of space mismatch"); dbg_err("LPT out of space mismatch at LEB %d:%d needing %d, done_ltab " "%d, done_lsave %d", lnum, offs, len, done_ltab, done_lsave); dbg_dump_lpt_info(c); dbg_dump_lpt_lebs(c); dump_stack(); return err; } /** * next_pnode_to_dirty - find next pnode to dirty. * @c: UBIFS file-system description object * @pnode: pnode * * This function returns the next pnode to dirty or %NULL if there are no more * pnodes. Note that pnodes that have never been written (lnum == 0) are * skipped. */ static struct ubifs_pnode *next_pnode_to_dirty(struct ubifs_info *c, struct ubifs_pnode *pnode) { struct ubifs_nnode *nnode; int iip; /* Try to go right */ nnode = pnode->parent; for (iip = pnode->iip + 1; iip < UBIFS_LPT_FANOUT; iip++) { if (nnode->nbranch[iip].lnum) return ubifs_get_pnode(c, nnode, iip); } /* Go up while can't go right */ do { iip = nnode->iip + 1; nnode = nnode->parent; if (!nnode) return NULL; for (; iip < UBIFS_LPT_FANOUT; iip++) { if (nnode->nbranch[iip].lnum) break; } } while (iip >= UBIFS_LPT_FANOUT); /* Go right */ nnode = ubifs_get_nnode(c, nnode, iip); if (IS_ERR(nnode)) return (void *)nnode; /* Go down to level 1 */ while (nnode->level > 1) { for (iip = 0; iip < UBIFS_LPT_FANOUT; iip++) { if (nnode->nbranch[iip].lnum) break; } if (iip >= UBIFS_LPT_FANOUT) { /* * Should not happen, but we need to keep going * if it does. */ iip = 0; } nnode = ubifs_get_nnode(c, nnode, iip); if (IS_ERR(nnode)) return (void *)nnode; } for (iip = 0; iip < UBIFS_LPT_FANOUT; iip++) if (nnode->nbranch[iip].lnum) break; if (iip >= UBIFS_LPT_FANOUT) /* Should not happen, but we need to keep going if it does */ iip = 0; return ubifs_get_pnode(c, nnode, iip); } /** * pnode_lookup - lookup a pnode in the LPT. * @c: UBIFS file-system description object * @i: pnode number (0 to main_lebs - 1) * * This function returns a pointer to the pnode on success or a negative * error code on failure. */ static struct ubifs_pnode *pnode_lookup(struct ubifs_info *c, int i) { int err, h, iip, shft; struct ubifs_nnode *nnode; if (!c->nroot) { err = ubifs_read_nnode(c, NULL, 0); if (err) return ERR_PTR(err); } i <<= UBIFS_LPT_FANOUT_SHIFT; nnode = c->nroot; 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)); return ubifs_get_pnode(c, nnode, iip); } /** * 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); } /** * do_make_pnode_dirty - mark a pnode dirty. * @c: UBIFS file-system description object * @pnode: pnode to mark dirty */ static void do_make_pnode_dirty(struct ubifs_info *c, struct ubifs_pnode *pnode) { /* Assumes cnext list is empty i.e. not called during commit */ if (!test_and_set_bit(DIRTY_CNODE, &pnode->flags)) { struct ubifs_nnode *nnode; c->dirty_pn_cnt += 1; add_pnode_dirt(c, pnode); /* Mark parent and ancestors dirty too */ nnode = pnode->parent; while (nnode) { if (!test_and_set_bit(DIRTY_CNODE, &nnode->flags)) { c->dirty_nn_cnt += 1; ubifs_add_nnode_dirt(c, nnode); nnode = nnode->parent; } else break; } } } /** * make_tree_dirty - mark the entire LEB properties tree dirty. * @c: UBIFS file-system description object * * This function is used by the "small" LPT model to cause the entire LEB * properties tree to be written. The "small" LPT model does not use LPT * garbage collection because it is more efficient to write the entire tree * (because it is small). * * This function returns %0 on success and a negative error code on failure. */ static int make_tree_dirty(struct ubifs_info *c) { struct ubifs_pnode *pnode; pnode = pnode_lookup(c, 0); if (IS_ERR(pnode)) return PTR_ERR(pnode); while (pnode) { do_make_pnode_dirty(c, pnode); pnode = next_pnode_to_dirty(c, pnode); if (IS_ERR(pnode)) return PTR_ERR(pnode); } return 0; } /** * need_write_all - determine if the LPT area is running out of free space. * @c: UBIFS file-system description object * * This function returns %1 if the LPT area is running out of free space and %0 * if it is not. */ static int need_write_all(struct ubifs_info *c) { long long free = 0; int i; for (i = 0; i < c->lpt_lebs; i++) { if (i + c->lpt_first == c->nhead_lnum) free += c->leb_size - c->nhead_offs; else if (c->ltab[i].free == c->leb_size) free += c->leb_size; else if (c->ltab[i].free + c->ltab[i].dirty == c->leb_size) free += c->leb_size; } /* Less than twice the size left */ if (free <= c->lpt_sz * 2) return 1; return 0; } /** * lpt_tgc_start - start trivial garbage collection of LPT LEBs. * @c: UBIFS file-system description object * * LPT trivial garbage collection is where a LPT LEB contains only dirty and * free space and so may be reused as soon as the next commit is completed. * This function is called during start commit to mark LPT LEBs for trivial GC. */ static void lpt_tgc_start(struct ubifs_info *c) { int i; for (i = 0; i < c->lpt_lebs; i++) { if (i + c->lpt_first == c->nhead_lnum) continue; if (c->ltab[i].dirty > 0 && c->ltab[i].free + c->ltab[i].dirty == c->leb_size) { c->ltab[i].tgc = 1; c->ltab[i].free = c->leb_size; c->ltab[i].dirty = 0; dbg_lp("LEB %d", i + c->lpt_first); } } } /** * lpt_tgc_end - end trivial garbage collection of LPT LEBs. * @c: UBIFS file-system description object * * LPT trivial garbage collection is where a LPT LEB contains only dirty and * free space and so may be reused as soon as the next commit is completed. * This function is called after the commit is completed (master node has been * written) and un-maps LPT LEBs that were marked for trivial GC. */ static int lpt_tgc_end(struct ubifs_info *c) { int i, err; for (i = 0; i < c->lpt_lebs; i++) if (c->ltab[i].tgc) { err = ubifs_leb_unmap(c, i + c->lpt_first); if (err) return err; c->ltab[i].tgc = 0; dbg_lp("LEB %d", i + c->lpt_first); } return 0; } /** * populate_lsave - fill the lsave array with important LEB numbers. * @c: the UBIFS file-system description object * * This function is only called for the "big" model. It records a small number * of LEB numbers of important LEBs. Important LEBs are ones that are (from * most important to least important): empty, freeable, freeable index, dirty * index, dirty or free. Upon mount, we read this list of LEB numbers and bring * their pnodes into memory. That will stop us from having to scan the LPT * straight away. For the "small" model we assume that scanning the LPT is no * big deal. */ static void populate_lsave(struct ubifs_info *c) { struct ubifs_lprops *lprops; struct ubifs_lpt_heap *heap; int i, cnt = 0; ubifs_assert(c->big_lpt); if (!(c->lpt_drty_flgs & LSAVE_DIRTY)) { c->lpt_drty_flgs |= LSAVE_DIRTY; ubifs_add_lpt_dirt(c, c->lsave_lnum, c->lsave_sz); } if (dbg_populate_lsave(c)) return; list_for_each_entry(lprops, &c->empty_list, list) { c->lsave[cnt++] = lprops->lnum; if (cnt >= c->lsave_cnt) return; } list_for_each_entry(lprops, &c->freeable_list, list) { c->lsave[cnt++] = lprops->lnum; if (cnt >= c->lsave_cnt) return; } list_for_each_entry(lprops, &c->frdi_idx_list, list) { c->lsave[cnt++] = lprops->lnum; if (cnt >= c->lsave_cnt) return; } heap = &c->lpt_heap[LPROPS_DIRTY_IDX - 1]; for (i = 0; i < heap->cnt; i++) { c->lsave[cnt++] = heap->arr[i]->lnum; if (cnt >= c->lsave_cnt) return; } heap = &c->lpt_heap[LPROPS_DIRTY - 1]; for (i = 0; i < heap->cnt; i++) { c->lsave[cnt++] = heap->arr[i]->lnum; if (cnt >= c->lsave_cnt) return; } heap = &c->lpt_heap[LPROPS_FREE - 1]; for (i = 0; i < heap->cnt; i++) { c->lsave[cnt++] = heap->arr[i]->lnum; if (cnt >= c->lsave_cnt) return; } /* Fill it up completely */ while (cnt < c->lsave_cnt) c->lsave[cnt++] = c->main_first; } /** * nnode_lookup - lookup a nnode in the LPT. * @c: UBIFS file-system description object * @i: nnode number * * This function returns a pointer to the nnode on success or a negative * error code on failure. */ static struct ubifs_nnode *nnode_lookup(struct ubifs_info *c, int i) { int err, iip; struct ubifs_nnode *nnode; if (!c->nroot) { err = ubifs_read_nnode(c, NULL, 0); if (err) return ERR_PTR(err); } nnode = c->nroot; while (1) { iip = i & (UBIFS_LPT_FANOUT - 1); i >>= UBIFS_LPT_FANOUT_SHIFT; if (!i) break; nnode = ubifs_get_nnode(c, nnode, iip); if (IS_ERR(nnode)) return nnode; } return nnode; } /** * make_nnode_dirty - find a nnode and, if found, make it dirty. * @c: UBIFS file-system description object * @node_num: nnode number of nnode to make dirty * @lnum: LEB number where nnode was written * @offs: offset where nnode was written * * This function is used by LPT garbage collection. LPT garbage collection is * used only for the "big" LPT model (c->big_lpt == 1). Garbage collection * simply involves marking all the nodes in the LEB being garbage-collected as * dirty. The dirty nodes are written next commit, after which the LEB is free * to be reused. * * This function returns %0 on success and a negative error code on failure. */ static int make_nnode_dirty(struct ubifs_info *c, int node_num, int lnum, int offs) { struct ubifs_nnode *nnode; nnode = nnode_lookup(c, node_num); if (IS_ERR(nnode)) return PTR_ERR(nnode); if (nnode->parent) { struct ubifs_nbranch *branch; branch = &nnode->parent->nbranch[nnode->iip]; if (branch->lnum != lnum || branch->offs != offs) return 0; /* nnode is obsolete */ } else if (c->lpt_lnum != lnum || c->lpt_offs != offs) return 0; /* nnode is obsolete */ /* Assumes cnext list is empty i.e. not called during commit */ if (!test_and_set_bit(DIRTY_CNODE, &nnode->flags)) { c->dirty_nn_cnt += 1; ubifs_add_nnode_dirt(c, nnode); /* Mark parent and ancestors dirty too */ nnode = nnode->parent; while (nnode) { if (!test_and_set_bit(DIRTY_CNODE, &nnode->flags)) { c->dirty_nn_cnt += 1; ubifs_add_nnode_dirt(c, nnode); nnode = nnode->parent; } else break; } } return 0; } /** * make_pnode_dirty - find a pnode and, if found, make it dirty. * @c: UBIFS file-system description object * @node_num: pnode number of pnode to make dirty * @lnum: LEB number where pnode was written * @offs: offset where pnode was written * * This function is used by LPT garbage collection. LPT garbage collection is * used only for the "big" LPT model (c->big_lpt == 1). Garbage collection * simply involves marking all the nodes in the LEB being garbage-collected as * dirty. The dirty nodes are written next commit, after which the LEB is free * to be reused. * * This function returns %0 on success and a negative error code on failure. */ static int make_pnode_dirty(struct ubifs_info *c, int node_num, int lnum, int offs) { struct ubifs_pnode *pnode; struct ubifs_nbranch *branch; pnode = pnode_lookup(c, node_num); if (IS_ERR(pnode)) return PTR_ERR(pnode); branch = &pnode->parent->nbranch[pnode->iip]; if (branch->lnum != lnum || branch->offs != offs) return 0; do_make_pnode_dirty(c, pnode); return 0; } /** * make_ltab_dirty - make ltab node dirty. * @c: UBIFS file-system description object * @lnum: LEB number where ltab was written * @offs: offset where ltab was written * * This function is used by LPT garbage collection. LPT garbage collection is * used only for the "big" LPT model (c->big_lpt == 1). Garbage collection * simply involves marking all the nodes in the LEB being garbage-collected as * dirty. The dirty nodes are written next commit, after which the LEB is free * to be reused. * * This function returns %0 on success and a negative error code on failure. */ static int make_ltab_dirty(struct ubifs_info *c, int lnum, int offs) { if (lnum != c->ltab_lnum || offs != c->ltab_offs) return 0; /* This ltab node is obsolete */ if (!(c->lpt_drty_flgs & LTAB_DIRTY)) { c->lpt_drty_flgs |= LTAB_DIRTY; ubifs_add_lpt_dirt(c, c->ltab_lnum, c->ltab_sz); } return 0; } /** * make_lsave_dirty - make lsave node dirty. * @c: UBIFS file-system description object * @lnum: LEB number where lsave was written * @offs: offset where lsave was written * * This function is used by LPT garbage collection. LPT garbage collection is * used only for the "big" LPT model (c->big_lpt == 1). Garbage collection * simply involves marking all the nodes in the LEB being garbage-collected as * dirty. The dirty nodes are written next commit, after which the LEB is free * to be reused. * * This function returns %0 on success and a negative error code on failure. */ static int make_lsave_dirty(struct ubifs_info *c, int lnum, int offs) { if (lnum != c->lsave_lnum || offs != c->lsave_offs) return 0; /* This lsave node is obsolete */ if (!(c->lpt_drty_flgs & LSAVE_DIRTY)) { c->lpt_drty_flgs |= LSAVE_DIRTY; ubifs_add_lpt_dirt(c, c->lsave_lnum, c->lsave_sz); } return 0; } /** * make_node_dirty - make node dirty. * @c: UBIFS file-system description object * @node_type: LPT node type * @node_num: node number * @lnum: LEB number where node was written * @offs: offset where node was written * * This function is used by LPT garbage collection. LPT garbage collection is * used only for the "big" LPT model (c->big_lpt == 1). Garbage collection * simply involves marking all the nodes in the LEB being garbage-collected as * dirty. The dirty nodes are written next commit, after which the LEB is free * to be reused. * * This function returns %0 on success and a negative error code on failure. */ static int make_node_dirty(struct ubifs_info *c, int node_type, int node_num, int lnum, int offs) { switch (node_type) { case UBIFS_LPT_NNODE: return make_nnode_dirty(c, node_num, lnum, offs); case UBIFS_LPT_PNODE: return make_pnode_dirty(c, node_num, lnum, offs); case UBIFS_LPT_LTAB: return make_ltab_dirty(c, lnum, offs); case UBIFS_LPT_LSAVE: return make_lsave_dirty(c, lnum, offs); } return -EINVAL; } /** * get_lpt_node_len - return the length of a node based on its type. * @c: UBIFS file-system description object * @node_type: LPT node type */ static int get_lpt_node_len(const struct ubifs_info *c, int node_type) { switch (node_type) { case UBIFS_LPT_NNODE: return c->nnode_sz; case UBIFS_LPT_PNODE: return c->pnode_sz; case UBIFS_LPT_LTAB: return c->ltab_sz; case UBIFS_LPT_LSAVE: return c->lsave_sz; } return 0; } /** * get_pad_len - return the length of padding in a buffer. * @c: UBIFS file-system description object * @buf: buffer * @len: length of buffer */ static int get_pad_len(const struct ubifs_info *c, uint8_t *buf, int len) { int offs, pad_len; if (c->min_io_size == 1) return 0; offs = c->leb_size - len; pad_len = ALIGN(offs, c->min_io_size) - offs; return pad_len; } /** * get_lpt_node_type - return type (and node number) of a node in a buffer. * @c: UBIFS file-system description object * @buf: buffer * @node_num: node number is returned here */ static int get_lpt_node_type(const struct ubifs_info *c, uint8_t *buf, int *node_num) { uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES; int pos = 0, node_type; node_type = ubifs_unpack_bits(&addr, &pos, UBIFS_LPT_TYPE_BITS); *node_num = ubifs_unpack_bits(&addr, &pos, c->pcnt_bits); return node_type; } /** * is_a_node - determine if a buffer contains a node. * @c: UBIFS file-system description object * @buf: buffer * @len: length of buffer * * This function returns %1 if the buffer contains a node or %0 if it does not. */ static int is_a_node(const struct ubifs_info *c, uint8_t *buf, int len) { uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES; int pos = 0, node_type, node_len; uint16_t crc, calc_crc; if (len < UBIFS_LPT_CRC_BYTES + (UBIFS_LPT_TYPE_BITS + 7) / 8) return 0; node_type = ubifs_unpack_bits(&addr, &pos, UBIFS_LPT_TYPE_BITS); if (node_type == UBIFS_LPT_NOT_A_NODE) return 0; node_len = get_lpt_node_len(c, node_type); if (!node_len || node_len > len) return 0; pos = 0; addr = buf; crc = ubifs_unpack_bits(&addr, &pos, UBIFS_LPT_CRC_BITS); calc_crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES, node_len - UBIFS_LPT_CRC_BYTES); if (crc != calc_crc) return 0; return 1; } /** * lpt_gc_lnum - garbage collect a LPT LEB. * @c: UBIFS file-system description object * @lnum: LEB number to garbage collect * * LPT garbage collection is used only for the "big" LPT model * (c->big_lpt == 1). Garbage collection simply involves marking all the nodes * in the LEB being garbage-collected as dirty. The dirty nodes are written * next commit, after which the LEB is free to be reused. * * This function returns %0 on success and a negative error code on failure. */ static int lpt_gc_lnum(struct ubifs_info *c, int lnum) { int err, len = c->leb_size, node_type, node_num, node_len, offs; void *buf = c->lpt_buf; dbg_lp("LEB %d", lnum); err = ubifs_leb_read(c, lnum, buf, 0, c->leb_size, 1); if (err) return err; while (1) { if (!is_a_node(c, buf, len)) { int pad_len; pad_len = get_pad_len(c, buf, len); if (pad_len) { buf += pad_len; len -= pad_len; continue; } return 0; } node_type = get_lpt_node_type(c, buf, &node_num); node_len = get_lpt_node_len(c, node_type); offs = c->leb_size - len; ubifs_assert(node_len != 0); mutex_lock(&c->lp_mutex); err = make_node_dirty(c, node_type, node_num, lnum, offs); mutex_unlock(&c->lp_mutex); if (err) return err; buf += node_len; len -= node_len; } return 0; } /** * lpt_gc - LPT garbage collection. * @c: UBIFS file-system description object * * Select a LPT LEB for LPT garbage collection and call 'lpt_gc_lnum()'. * Returns %0 on success and a negative error code on failure. */ static int lpt_gc(struct ubifs_info *c) { int i, lnum = -1, dirty = 0; mutex_lock(&c->lp_mutex); for (i = 0; i < c->lpt_lebs; i++) { ubifs_assert(!c->ltab[i].tgc); if (i + c->lpt_first == c->nhead_lnum || c->ltab[i].free + c->ltab[i].dirty == c->leb_size) continue; if (c->ltab[i].dirty > dirty) { dirty = c->ltab[i].dirty; lnum = i + c->lpt_first; } } mutex_unlock(&c->lp_mutex); if (lnum == -1) return -ENOSPC; return lpt_gc_lnum(c, lnum); } /** * ubifs_lpt_start_commit - UBIFS commit starts. * @c: the UBIFS file-system description object * * This function has to be called when UBIFS starts the commit operation. * This function "freezes" all currently dirty LEB properties and does not * change them anymore. Further changes are saved and tracked separately * because they are not part of this commit. This function returns zero in case * of success and a negative error code in case of failure. */ int ubifs_lpt_start_commit(struct ubifs_info *c) { int err, cnt; dbg_lp(""); mutex_lock(&c->lp_mutex); err = dbg_chk_lpt_free_spc(c); if (err) goto out; err = dbg_check_ltab(c); if (err) goto out; if (c->check_lpt_free) { /* * We ensure there is enough free space in * ubifs_lpt_post_commit() by marking nodes dirty. That * information is lost when we unmount, so we also need * to check free space once after mounting also. */ c->check_lpt_free = 0; while (need_write_all(c)) { mutex_unlock(&c->lp_mutex); err = lpt_gc(c); if (err) return err; mutex_lock(&c->lp_mutex); } } lpt_tgc_start(c); if (!c->dirty_pn_cnt) { dbg_cmt("no cnodes to commit"); err = 0; goto out; } if (!c->big_lpt && need_write_all(c)) { /* If needed, write everything */ err = make_tree_dirty(c); if (err) goto out; lpt_tgc_start(c); } if (c->big_lpt) populate_lsave(c); cnt = get_cnodes_to_commit(c); ubifs_assert(cnt != 0); err = layout_cnodes(c); if (err) goto out; /* Copy the LPT's own lprops for end commit to write */ memcpy(c->ltab_cmt, c->ltab, sizeof(struct ubifs_lpt_lprops) * c->lpt_lebs); c->lpt_drty_flgs &= ~(LTAB_DIRTY | LSAVE_DIRTY); out: mutex_unlock(&c->lp_mutex); return err; } /** * free_obsolete_cnodes - free obsolete cnodes for commit end. * @c: UBIFS file-system description object */ static void free_obsolete_cnodes(struct ubifs_info *c) { struct ubifs_cnode *cnode, *cnext; cnext = c->lpt_cnext; if (!cnext) return; do { cnode = cnext; cnext = cnode->cnext; if (test_bit(OBSOLETE_CNODE, &cnode->flags)) kfree(cnode); else cnode->cnext = NULL; } while (cnext != c->lpt_cnext); c->lpt_cnext = NULL; } /** * ubifs_lpt_end_commit - finish the commit operation. * @c: the UBIFS file-system description object * * This function has to be called when the commit operation finishes. It * flushes the changes which were "frozen" by 'ubifs_lprops_start_commit()' to * the media. Returns zero in case of success and a negative error code in case * of failure. */ int ubifs_lpt_end_commit(struct ubifs_info *c) { int err; dbg_lp(""); if (!c->lpt_cnext) return 0; err = write_cnodes(c); if (err) return err; mutex_lock(&c->lp_mutex); free_obsolete_cnodes(c); mutex_unlock(&c->lp_mutex); return 0; } /** * ubifs_lpt_post_commit - post commit LPT trivial GC and LPT GC. * @c: UBIFS file-system description object * * LPT trivial GC is completed after a commit. Also LPT GC is done after a * commit for the "big" LPT model. */ int ubifs_lpt_post_commit(struct ubifs_info *c) { int err; mutex_lock(&c->lp_mutex); err = lpt_tgc_end(c); if (err) goto out; if (c->big_lpt) while (need_write_all(c)) { mutex_unlock(&c->lp_mutex); err = lpt_gc(c); if (err) return err; mutex_lock(&c->lp_mutex); } out: mutex_unlock(&c->lp_mutex); return err; } /** * first_nnode - find the first nnode in memory. * @c: UBIFS file-system description object * @hght: height of tree where nnode found is returned here * * This function returns a pointer to the nnode found or %NULL if no nnode is * found. This function is a helper to 'ubifs_lpt_free()'. */ static struct ubifs_nnode *first_nnode(struct ubifs_info *c, int *hght) { struct ubifs_nnode *nnode; int h, i, found; nnode = c->nroot; *hght = 0; if (!nnode) return NULL; for (h = 1; h < c->lpt_hght; h++) { found = 0; for (i = 0; i < UBIFS_LPT_FANOUT; i++) { if (nnode->nbranch[i].nnode) { found = 1; nnode = nnode->nbranch[i].nnode; *hght = h; break; } } if (!found) break; } return nnode; } /** * next_nnode - find the next nnode in memory. * @c: UBIFS file-system description object * @nnode: nnode from which to start. * @hght: height of tree where nnode is, is passed and returned here * * This function returns a pointer to the nnode found or %NULL if no nnode is * found. This function is a helper to 'ubifs_lpt_free()'. */ static struct ubifs_nnode *next_nnode(struct ubifs_info *c, struct ubifs_nnode *nnode, int *hght) { struct ubifs_nnode *parent; int iip, h, i, found; parent = nnode->parent; if (!parent) return NULL; if (nnode->iip == UBIFS_LPT_FANOUT - 1) { *hght -= 1; return parent; } for (iip = nnode->iip + 1; iip < UBIFS_LPT_FANOUT; iip++) { nnode = parent->nbranch[iip].nnode; if (nnode) break; } if (!nnode) { *hght -= 1; return parent; } for (h = *hght + 1; h < c->lpt_hght; h++) { found = 0; for (i = 0; i < UBIFS_LPT_FANOUT; i++) { if (nnode->nbranch[i].nnode) { found = 1; nnode = nnode->nbranch[i].nnode; *hght = h; break; } } if (!found) break; } return nnode; } /** * ubifs_lpt_free - free resources owned by the LPT. * @c: UBIFS file-system description object * @wr_only: free only resources used for writing */ void ubifs_lpt_free(struct ubifs_info *c, int wr_only) { struct ubifs_nnode *nnode; int i, hght; /* Free write-only things first */ free_obsolete_cnodes(c); /* Leftover from a failed commit */ vfree(c->ltab_cmt); c->ltab_cmt = NULL; vfree(c->lpt_buf); c->lpt_buf = NULL; kfree(c->lsave); c->lsave = NULL; if (wr_only) return; /* Now free the rest */ nnode = first_nnode(c, &hght); while (nnode) { for (i = 0; i < UBIFS_LPT_FANOUT; i++) kfree(nnode->nbranch[i].nnode); nnode = next_nnode(c, nnode, &hght); } for (i = 0; i < LPROPS_HEAP_CNT; i++) kfree(c->lpt_heap[i].arr); kfree(c->dirty_idx.arr); kfree(c->nroot); vfree(c->ltab); kfree(c->lpt_nod_buf); } #ifdef CONFIG_UBIFS_FS_DEBUG /** * dbg_is_all_ff - determine if a buffer contains only 0xFF bytes. * @buf: buffer * @len: buffer length */ static int dbg_is_all_ff(uint8_t *buf, int len) { int i; for (i = 0; i < len; i++) if (buf[i] != 0xff) return 0; return 1; } /** * dbg_is_nnode_dirty - determine if a nnode is dirty. * @c: the UBIFS file-system description object * @lnum: LEB number where nnode was written * @offs: offset where nnode was written */ static int dbg_is_nnode_dirty(struct ubifs_info *c, int lnum, int offs) { struct ubifs_nnode *nnode; int hght; /* Entire tree is in memory so first_nnode / next_nnode are OK */ nnode = first_nnode(c, &hght); for (; nnode; nnode = next_nnode(c, nnode, &hght)) { struct ubifs_nbranch *branch; cond_resched(); if (nnode->parent) { branch = &nnode->parent->nbranch[nnode->iip]; if (branch->lnum != lnum || branch->offs != offs) continue; if (test_bit(DIRTY_CNODE, &nnode->flags)) return 1; return 0; } else { if (c->lpt_lnum != lnum || c->lpt_offs != offs) continue; if (test_bit(DIRTY_CNODE, &nnode->flags)) return 1; return 0; } } return 1; } /** * dbg_is_pnode_dirty - determine if a pnode is dirty. * @c: the UBIFS file-system description object * @lnum: LEB number where pnode was written * @offs: offset where pnode was written */ static int dbg_is_pnode_dirty(struct ubifs_info *c, int lnum, int offs) { int i, cnt; cnt = DIV_ROUND_UP(c->main_lebs, UBIFS_LPT_FANOUT); for (i = 0; i < cnt; i++) { struct ubifs_pnode *pnode; struct ubifs_nbranch *branch; cond_resched(); pnode = pnode_lookup(c, i); if (IS_ERR(pnode)) return PTR_ERR(pnode); branch = &pnode->parent->nbranch[pnode->iip]; if (branch->lnum != lnum || branch->offs != offs) continue; if (test_bit(DIRTY_CNODE, &pnode->flags)) return 1; return 0; } return 1; } /** * dbg_is_ltab_dirty - determine if a ltab node is dirty. * @c: the UBIFS file-system description object * @lnum: LEB number where ltab node was written * @offs: offset where ltab node was written */ static int dbg_is_ltab_dirty(struct ubifs_info *c, int lnum, int offs) { if (lnum != c->ltab_lnum || offs != c->ltab_offs) return 1; return (c->lpt_drty_flgs & LTAB_DIRTY) != 0; } /** * dbg_is_lsave_dirty - determine if a lsave node is dirty. * @c: the UBIFS file-system description object * @lnum: LEB number where lsave node was written * @offs: offset where lsave node was written */ static int dbg_is_lsave_dirty(struct ubifs_info *c, int lnum, int offs) { if (lnum != c->lsave_lnum || offs != c->lsave_offs) return 1; return (c->lpt_drty_flgs & LSAVE_DIRTY) != 0; } /** * dbg_is_node_dirty - determine if a node is dirty. * @c: the UBIFS file-system description object * @node_type: node type * @lnum: LEB number where node was written * @offs: offset where node was written */ static int dbg_is_node_dirty(struct ubifs_info *c, int node_type, int lnum, int offs) { switch (node_type) { case UBIFS_LPT_NNODE: return dbg_is_nnode_dirty(c, lnum, offs); case UBIFS_LPT_PNODE: return dbg_is_pnode_dirty(c, lnum, offs); case UBIFS_LPT_LTAB: return dbg_is_ltab_dirty(c, lnum, offs); case UBIFS_LPT_LSAVE: return dbg_is_lsave_dirty(c, lnum, offs); } return 1; } /** * dbg_check_ltab_lnum - check the ltab for a LPT LEB number. * @c: the UBIFS file-system description object * @lnum: LEB number where node was written * @offs: offset where node was written * * This function returns %0 on success and a negative error code on failure. */ static int dbg_check_ltab_lnum(struct ubifs_info *c, int lnum) { int err, len = c->leb_size, dirty = 0, node_type, node_num, node_len; int ret; void *buf, *p; if (!dbg_is_chk_lprops(c)) return 0; buf = p = __vmalloc(c->leb_size, GFP_NOFS, PAGE_KERNEL); if (!buf) { ubifs_err("cannot allocate memory for ltab checking"); return 0; } dbg_lp("LEB %d", lnum); err = ubifs_leb_read(c, lnum, buf, 0, c->leb_size, 1); if (err) goto out; while (1) { if (!is_a_node(c, p, len)) { int i, pad_len; pad_len = get_pad_len(c, p, len); if (pad_len) { p += pad_len; len -= pad_len; dirty += pad_len; continue; } if (!dbg_is_all_ff(p, len)) { dbg_msg("invalid empty space in LEB %d at %d", lnum, c->leb_size - len); err = -EINVAL; } i = lnum - c->lpt_first; if (len != c->ltab[i].free) { dbg_msg("invalid free space in LEB %d " "(free %d, expected %d)", lnum, len, c->ltab[i].free); err = -EINVAL; } if (dirty != c->ltab[i].dirty) { dbg_msg("invalid dirty space in LEB %d " "(dirty %d, expected %d)", lnum, dirty, c->ltab[i].dirty); err = -EINVAL; } goto out; } node_type = get_lpt_node_type(c, p, &node_num); node_len = get_lpt_node_len(c, node_type); ret = dbg_is_node_dirty(c, node_type, lnum, c->leb_size - len); if (ret == 1) dirty += node_len; p += node_len; len -= node_len; } err = 0; out: vfree(buf); return err; } /** * dbg_check_ltab - check the free and dirty space in the ltab. * @c: the UBIFS file-system description object * * This function returns %0 on success and a negative error code on failure. */ int dbg_check_ltab(struct ubifs_info *c) { int lnum, err, i, cnt; if (!dbg_is_chk_lprops(c)) return 0; /* Bring the entire tree into memory */ cnt = DIV_ROUND_UP(c->main_lebs, UBIFS_LPT_FANOUT); for (i = 0; i < cnt; i++) { struct ubifs_pnode *pnode; pnode = pnode_lookup(c, i); if (IS_ERR(pnode)) return PTR_ERR(pnode); cond_resched(); } /* Check nodes */ err = dbg_check_lpt_nodes(c, (struct ubifs_cnode *)c->nroot, 0, 0); if (err) return err; /* Check each LEB */ for (lnum = c->lpt_first; lnum <= c->lpt_last; lnum++) { err = dbg_check_ltab_lnum(c, lnum); if (err) { dbg_err("failed at LEB %d", lnum); return err; } } dbg_lp("succeeded"); return 0; } /** * dbg_chk_lpt_free_spc - check LPT free space is enough to write entire LPT. * @c: the UBIFS file-system description object * * This function returns %0 on success and a negative error code on failure. */ int dbg_chk_lpt_free_spc(struct ubifs_info *c) { long long free = 0; int i; if (!dbg_is_chk_lprops(c)) return 0; for (i = 0; i < c->lpt_lebs; i++) { if (c->ltab[i].tgc || c->ltab[i].cmt) continue; if (i + c->lpt_first == c->nhead_lnum) free += c->leb_size - c->nhead_offs; else if (c->ltab[i].free == c->leb_size) free += c->leb_size; } if (free < c->lpt_sz) { dbg_err("LPT space error: free %lld lpt_sz %lld", free, c->lpt_sz); dbg_dump_lpt_info(c); dbg_dump_lpt_lebs(c); dump_stack(); return -EINVAL; } return 0; } /** * dbg_chk_lpt_sz - check LPT does not write more than LPT size. * @c: the UBIFS file-system description object * @action: what to do * @len: length written * * This function returns %0 on success and a negative error code on failure. * The @action argument may be one of: * o %0 - LPT debugging checking starts, initialize debugging variables; * o %1 - wrote an LPT node, increase LPT size by @len bytes; * o %2 - switched to a different LEB and wasted @len bytes; * o %3 - check that we've written the right number of bytes. * o %4 - wasted @len bytes; */ int dbg_chk_lpt_sz(struct ubifs_info *c, int action, int len) { struct ubifs_debug_info *d = c->dbg; long long chk_lpt_sz, lpt_sz; int err = 0; if (!dbg_is_chk_lprops(c)) return 0; switch (action) { case 0: d->chk_lpt_sz = 0; d->chk_lpt_sz2 = 0; d->chk_lpt_lebs = 0; d->chk_lpt_wastage = 0; if (c->dirty_pn_cnt > c->pnode_cnt) { dbg_err("dirty pnodes %d exceed max %d", c->dirty_pn_cnt, c->pnode_cnt); err = -EINVAL; } if (c->dirty_nn_cnt > c->nnode_cnt) { dbg_err("dirty nnodes %d exceed max %d", c->dirty_nn_cnt, c->nnode_cnt); err = -EINVAL; } return err; case 1: d->chk_lpt_sz += len; return 0; case 2: d->chk_lpt_sz += len; d->chk_lpt_wastage += len; d->chk_lpt_lebs += 1; return 0; case 3: chk_lpt_sz = c->leb_size; chk_lpt_sz *= d->chk_lpt_lebs; chk_lpt_sz += len - c->nhead_offs; if (d->chk_lpt_sz != chk_lpt_sz) { dbg_err("LPT wrote %lld but space used was %lld", d->chk_lpt_sz, chk_lpt_sz); err = -EINVAL; } if (d->chk_lpt_sz > c->lpt_sz) { dbg_err("LPT wrote %lld but lpt_sz is %lld", d->chk_lpt_sz, c->lpt_sz); err = -EINVAL; } if (d->chk_lpt_sz2 && d->chk_lpt_sz != d->chk_lpt_sz2) { dbg_err("LPT layout size %lld but wrote %lld", d->chk_lpt_sz, d->chk_lpt_sz2); err = -EINVAL; } if (d->chk_lpt_sz2 && d->new_nhead_offs != len) { dbg_err("LPT new nhead offs: expected %d was %d", d->new_nhead_offs, len); err = -EINVAL; } lpt_sz = (long long)c->pnode_cnt * c->pnode_sz; lpt_sz += (long long)c->nnode_cnt * c->nnode_sz; lpt_sz += c->ltab_sz; if (c->big_lpt) lpt_sz += c->lsave_sz; if (d->chk_lpt_sz - d->chk_lpt_wastage > lpt_sz) { dbg_err("LPT chk_lpt_sz %lld + waste %lld exceeds %lld", d->chk_lpt_sz, d->chk_lpt_wastage, lpt_sz); err = -EINVAL; } if (err) { dbg_dump_lpt_info(c); dbg_dump_lpt_lebs(c); dump_stack(); } d->chk_lpt_sz2 = d->chk_lpt_sz; d->chk_lpt_sz = 0; d->chk_lpt_wastage = 0; d->chk_lpt_lebs = 0; d->new_nhead_offs = len; return err; case 4: d->chk_lpt_sz += len; d->chk_lpt_wastage += len; return 0; default: return -EINVAL; } } /** * dbg_dump_lpt_leb - dump an LPT LEB. * @c: UBIFS file-system description object * @lnum: LEB number to dump * * This function dumps an LEB from LPT area. Nodes in this area are very * different to nodes in the main area (e.g., they do not have common headers, * they do not have 8-byte alignments, etc), so we have a separate function to * dump LPT area LEBs. Note, LPT has to be locked by the caller. */ static void dump_lpt_leb(const struct ubifs_info *c, int lnum) { int err, len = c->leb_size, node_type, node_num, node_len, offs; void *buf, *p; printk(KERN_DEBUG "(pid %d) start dumping LEB %d\n", current->pid, lnum); buf = p = __vmalloc(c->leb_size, GFP_NOFS, PAGE_KERNEL); if (!buf) { ubifs_err("cannot allocate memory to dump LPT"); return; } err = ubifs_leb_read(c, lnum, buf, 0, c->leb_size, 1); if (err) goto out; while (1) { offs = c->leb_size - len; if (!is_a_node(c, p, len)) { int pad_len; pad_len = get_pad_len(c, p, len); if (pad_len) { printk(KERN_DEBUG "LEB %d:%d, pad %d bytes\n", lnum, offs, pad_len); p += pad_len; len -= pad_len; continue; } if (len) printk(KERN_DEBUG "LEB %d:%d, free %d bytes\n", lnum, offs, len); break; } node_type = get_lpt_node_type(c, p, &node_num); switch (node_type) { case UBIFS_LPT_PNODE: { node_len = c->pnode_sz; if (c->big_lpt) printk(KERN_DEBUG "LEB %d:%d, pnode num %d\n", lnum, offs, node_num); else printk(KERN_DEBUG "LEB %d:%d, pnode\n", lnum, offs); break; } case UBIFS_LPT_NNODE: { int i; struct ubifs_nnode nnode; node_len = c->nnode_sz; if (c->big_lpt) printk(KERN_DEBUG "LEB %d:%d, nnode num %d, ", lnum, offs, node_num); else printk(KERN_DEBUG "LEB %d:%d, nnode, ", lnum, offs); err = ubifs_unpack_nnode(c, p, &nnode); for (i = 0; i < UBIFS_LPT_FANOUT; i++) { printk(KERN_CONT "%d:%d", nnode.nbranch[i].lnum, nnode.nbranch[i].offs); if (i != UBIFS_LPT_FANOUT - 1) printk(KERN_CONT ", "); } printk(KERN_CONT "\n"); break; } case UBIFS_LPT_LTAB: node_len = c->ltab_sz; printk(KERN_DEBUG "LEB %d:%d, ltab\n", lnum, offs); break; case UBIFS_LPT_LSAVE: node_len = c->lsave_sz; printk(KERN_DEBUG "LEB %d:%d, lsave len\n", lnum, offs); break; default: ubifs_err("LPT node type %d not recognized", node_type); goto out; } p += node_len; len -= node_len; } printk(KERN_DEBUG "(pid %d) finish dumping LEB %d\n", current->pid, lnum); out: vfree(buf); return; } /** * dbg_dump_lpt_lebs - dump LPT lebs. * @c: UBIFS file-system description object * * This function dumps all LPT LEBs. The caller has to make sure the LPT is * locked. */ void dbg_dump_lpt_lebs(const struct ubifs_info *c) { int i; printk(KERN_DEBUG "(pid %d) start dumping all LPT LEBs\n", current->pid); for (i = 0; i < c->lpt_lebs; i++) dump_lpt_leb(c, i + c->lpt_first); printk(KERN_DEBUG "(pid %d) finish dumping all LPT LEBs\n", current->pid); } /** * dbg_populate_lsave - debugging version of 'populate_lsave()' * @c: UBIFS file-system description object * * This is a debugging version for 'populate_lsave()' which populates lsave * with random LEBs instead of useful LEBs, which is good for test coverage. * Returns zero if lsave has not been populated (this debugging feature is * disabled) an non-zero if lsave has been populated. */ static int dbg_populate_lsave(struct ubifs_info *c) { struct ubifs_lprops *lprops; struct ubifs_lpt_heap *heap; int i; if (!dbg_is_chk_gen(c)) return 0; if (random32() & 3) return 0; for (i = 0; i < c->lsave_cnt; i++) c->lsave[i] = c->main_first; list_for_each_entry(lprops, &c->empty_list, list) c->lsave[random32() % c->lsave_cnt] = lprops->lnum; list_for_each_entry(lprops, &c->freeable_list, list) c->lsave[random32() % c->lsave_cnt] = lprops->lnum; list_for_each_entry(lprops, &c->frdi_idx_list, list) c->lsave[random32() % c->lsave_cnt] = lprops->lnum; heap = &c->lpt_heap[LPROPS_DIRTY_IDX - 1]; for (i = 0; i < heap->cnt; i++) c->lsave[random32() % c->lsave_cnt] = heap->arr[i]->lnum; heap = &c->lpt_heap[LPROPS_DIRTY - 1]; for (i = 0; i < heap->cnt; i++) c->lsave[random32() % c->lsave_cnt] = heap->arr[i]->lnum; heap = &c->lpt_heap[LPROPS_FREE - 1]; for (i = 0; i < heap->cnt; i++) c->lsave[random32() % c->lsave_cnt] = heap->arr[i]->lnum; return 1; } #endif /* CONFIG_UBIFS_FS_DEBUG */