| /* |
| * 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 <linux/crc16.h> |
| #include "ubifs.h" |
| |
| /** |
| * 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_ZNODE, &cnode->flags)); |
| __set_bit(COW_ZNODE, &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_ZNODE, &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_PTR(PTR_ERR(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); |
| 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); |
| } |
| 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 = ubi_read(c->ubi, lnum, buf, 0, c->leb_size); |
| if (err) { |
| ubifs_err("cannot read LEB %d, error %d", lnum, 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 = c->dbg->buf; |
| |
| if (!(ubifs_chk_flags & UBIFS_CHK_LPROPS)) |
| return 0; |
| |
| dbg_lp("LEB %d", lnum); |
| err = ubi_read(c->ubi, lnum, buf, 0, c->leb_size); |
| if (err) { |
| dbg_msg("ubi_read failed, LEB %d, error %d", lnum, err); |
| return err; |
| } |
| while (1) { |
| if (!is_a_node(c, buf, len)) { |
| int i, pad_len; |
| |
| pad_len = get_pad_len(c, buf, len); |
| if (pad_len) { |
| buf += pad_len; |
| len -= pad_len; |
| dirty += pad_len; |
| continue; |
| } |
| if (!dbg_is_all_ff(buf, 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; |
| } |
| return err; |
| } |
| node_type = get_lpt_node_type(c, buf, &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; |
| buf += node_len; |
| len -= node_len; |
| } |
| } |
| |
| /** |
| * 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 (!(ubifs_chk_flags & UBIFS_CHK_LPROPS)) |
| 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 (!(ubifs_chk_flags & UBIFS_CHK_LPROPS)) |
| 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 (!(ubifs_chk_flags & UBIFS_CHK_LPROPS)) |
| 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 = c->dbg->buf; |
| |
| printk(KERN_DEBUG "(pid %d) start dumping LEB %d\n", |
| current->pid, lnum); |
| err = ubi_read(c->ubi, lnum, buf, 0, c->leb_size); |
| if (err) { |
| ubifs_err("cannot read LEB %d, error %d", lnum, err); |
| return; |
| } |
| while (1) { |
| offs = c->leb_size - len; |
| if (!is_a_node(c, buf, len)) { |
| int pad_len; |
| |
| pad_len = get_pad_len(c, buf, len); |
| if (pad_len) { |
| printk(KERN_DEBUG "LEB %d:%d, pad %d bytes\n", |
| lnum, offs, pad_len); |
| buf += 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, buf, &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, buf, &nnode); |
| for (i = 0; i < UBIFS_LPT_FANOUT; i++) { |
| printk("%d:%d", nnode.nbranch[i].lnum, |
| nnode.nbranch[i].offs); |
| if (i != UBIFS_LPT_FANOUT - 1) |
| printk(", "); |
| } |
| printk("\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); |
| return; |
| } |
| |
| buf += node_len; |
| len -= node_len; |
| } |
| |
| printk(KERN_DEBUG "(pid %d) finish dumping LEB %d\n", |
| current->pid, lnum); |
| } |
| |
| /** |
| * 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); |
| } |
| |
| #endif /* CONFIG_UBIFS_FS_DEBUG */ |