summaryrefslogtreecommitdiff
path: root/mkfs.ubifs/lpt.c
diff options
context:
space:
mode:
authorArtem Bityutskiy <Artem.Bityutskiy@nokia.com>2008-08-19 13:18:07 +0300
committerArtem Bityutskiy <Artem.Bityutskiy@nokia.com>2008-08-19 13:20:49 +0300
commit36ec51948e0ecbf8cb9c5e44fbba5214451ee81c (patch)
treee0f613c22d1b7a83512ad04b0b9b76dcb09199d9 /mkfs.ubifs/lpt.c
parent71e18cc40c6a275e01c166ffeb68c5ed8759caf0 (diff)
Add mkfs.ubifs
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Diffstat (limited to 'mkfs.ubifs/lpt.c')
-rw-r--r--mkfs.ubifs/lpt.c577
1 files changed, 577 insertions, 0 deletions
diff --git a/mkfs.ubifs/lpt.c b/mkfs.ubifs/lpt.c
new file mode 100644
index 0000000..48ae03f
--- /dev/null
+++ b/mkfs.ubifs/lpt.c
@@ -0,0 +1,577 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006, 2007 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
+ */
+
+#include "mkfs.ubifs.h"
+
+/**
+ * do_calc_lpt_geom - calculate sizes for the LPT area.
+ * @c: the UBIFS file-system description object
+ *
+ * Calculate the sizes of LPT bit fields, nodes, and tree, based on the
+ * properties of the flash and whether LPT is "big" (c->big_lpt).
+ */
+static void do_calc_lpt_geom(struct ubifs_info *c)
+{
+ int n, bits, per_leb_wastage;
+ long long sz, tot_wastage;
+
+ c->pnode_cnt = (c->main_lebs + UBIFS_LPT_FANOUT - 1) / UBIFS_LPT_FANOUT;
+
+ n = (c->pnode_cnt + UBIFS_LPT_FANOUT - 1) / UBIFS_LPT_FANOUT;
+ c->nnode_cnt = n;
+ while (n > 1) {
+ n = (n + UBIFS_LPT_FANOUT - 1) / UBIFS_LPT_FANOUT;
+ c->nnode_cnt += n;
+ }
+
+ c->lpt_hght = 1;
+ n = UBIFS_LPT_FANOUT;
+ while (n < c->pnode_cnt) {
+ c->lpt_hght += 1;
+ n <<= UBIFS_LPT_FANOUT_SHIFT;
+ }
+
+ c->space_bits = fls(c->leb_size) - 3;
+ c->lpt_lnum_bits = fls(c->lpt_lebs);
+ c->lpt_offs_bits = fls(c->leb_size - 1);
+ c->lpt_spc_bits = fls(c->leb_size);
+
+ n = (c->max_leb_cnt + UBIFS_LPT_FANOUT - 1) / UBIFS_LPT_FANOUT;
+ c->pcnt_bits = fls(n - 1);
+
+ c->lnum_bits = fls(c->max_leb_cnt - 1);
+
+ bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS +
+ (c->big_lpt ? c->pcnt_bits : 0) +
+ (c->space_bits * 2 + 1) * UBIFS_LPT_FANOUT;
+ c->pnode_sz = (bits + 7) / 8;
+
+ bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS +
+ (c->big_lpt ? c->pcnt_bits : 0) +
+ (c->lpt_lnum_bits + c->lpt_offs_bits) * UBIFS_LPT_FANOUT;
+ c->nnode_sz = (bits + 7) / 8;
+
+ bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS +
+ c->lpt_lebs * c->lpt_spc_bits * 2;
+ c->ltab_sz = (bits + 7) / 8;
+
+ bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS +
+ c->lnum_bits * c->lsave_cnt;
+ c->lsave_sz = (bits + 7) / 8;
+
+ /* Calculate the minimum LPT size */
+ c->lpt_sz = (long long)c->pnode_cnt * c->pnode_sz;
+ c->lpt_sz += (long long)c->nnode_cnt * c->nnode_sz;
+ c->lpt_sz += c->ltab_sz;
+ c->lpt_sz += c->lsave_sz;
+
+ /* Add wastage */
+ sz = c->lpt_sz;
+ per_leb_wastage = max_t(int, c->pnode_sz, c->nnode_sz);
+ sz += per_leb_wastage;
+ tot_wastage = per_leb_wastage;
+ while (sz > c->leb_size) {
+ sz += per_leb_wastage;
+ sz -= c->leb_size;
+ tot_wastage += per_leb_wastage;
+ }
+ tot_wastage += ALIGN(sz, c->min_io_size) - sz;
+ c->lpt_sz += tot_wastage;
+}
+
+/**
+ * calc_dflt_lpt_geom - calculate default LPT geometry.
+ * @c: the UBIFS file-system description object
+ * @main_lebs: number of main area LEBs is passed and returned here
+ * @big_lpt: whether the LPT area is "big" is returned here
+ *
+ * The size of the LPT area depends on parameters that themselves are dependent
+ * on the size of the LPT area. This function, successively recalculates the LPT
+ * area geometry until the parameters and resultant geometry are consistent.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int calc_dflt_lpt_geom(struct ubifs_info *c, int *main_lebs, int *big_lpt)
+{
+ int i, lebs_needed;
+ long long sz;
+
+ /* Start by assuming the minimum number of LPT LEBs */
+ c->lpt_lebs = UBIFS_MIN_LPT_LEBS;
+ c->main_lebs = *main_lebs - c->lpt_lebs;
+ if (c->main_lebs <= 0)
+ return -EINVAL;
+
+ /* And assume we will use the small LPT model */
+ c->big_lpt = 0;
+
+ /*
+ * Calculate the geometry based on assumptions above and then see if it
+ * makes sense
+ */
+ do_calc_lpt_geom(c);
+
+ /* Small LPT model must have lpt_sz < leb_size */
+ if (c->lpt_sz > c->leb_size) {
+ /* Nope, so try again using big LPT model */
+ c->big_lpt = 1;
+ do_calc_lpt_geom(c);
+ }
+
+ /* Now check there are enough LPT LEBs */
+ for (i = 0; i < 64 ; i++) {
+ sz = c->lpt_sz * 4; /* Allow 4 times the size */
+ sz += c->leb_size - 1;
+ do_div(sz, c->leb_size);
+ lebs_needed = sz;
+ if (lebs_needed > c->lpt_lebs) {
+ /* Not enough LPT LEBs so try again with more */
+ c->lpt_lebs = lebs_needed;
+ c->main_lebs = *main_lebs - c->lpt_lebs;
+ if (c->main_lebs <= 0)
+ return -EINVAL;
+ do_calc_lpt_geom(c);
+ continue;
+ }
+ if (c->ltab_sz > c->leb_size) {
+ err_msg("LPT ltab too big");
+ return -EINVAL;
+ }
+ *main_lebs = c->main_lebs;
+ *big_lpt = c->big_lpt;
+ return 0;
+ }
+ return -EINVAL;
+}
+
+/**
+ * pack_bits - pack bit fields end-to-end.
+ * @addr: address at which to pack (passed and next address returned)
+ * @pos: bit position at which to pack (passed and next position returned)
+ * @val: value to pack
+ * @nrbits: number of bits of value to pack (1-32)
+ */
+static void pack_bits(uint8_t **addr, int *pos, uint32_t val, int nrbits)
+{
+ uint8_t *p = *addr;
+ int b = *pos;
+
+ if (b) {
+ *p |= ((uint8_t)val) << b;
+ nrbits += b;
+ if (nrbits > 8) {
+ *++p = (uint8_t)(val >>= (8 - b));
+ if (nrbits > 16) {
+ *++p = (uint8_t)(val >>= 8);
+ if (nrbits > 24) {
+ *++p = (uint8_t)(val >>= 8);
+ if (nrbits > 32)
+ *++p = (uint8_t)(val >>= 8);
+ }
+ }
+ }
+ } else {
+ *p = (uint8_t)val;
+ if (nrbits > 8) {
+ *++p = (uint8_t)(val >>= 8);
+ if (nrbits > 16) {
+ *++p = (uint8_t)(val >>= 8);
+ if (nrbits > 24)
+ *++p = (uint8_t)(val >>= 8);
+ }
+ }
+ }
+ b = nrbits & 7;
+ if (b == 0)
+ p++;
+ *addr = p;
+ *pos = b;
+}
+
+/**
+ * pack_pnode - pack all the bit fields of a pnode.
+ * @c: UBIFS file-system description object
+ * @buf: buffer into which to pack
+ * @pnode: pnode to pack
+ */
+static void pack_pnode(struct ubifs_info *c, void *buf,
+ struct ubifs_pnode *pnode)
+{
+ uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
+ int i, pos = 0;
+ uint16_t crc;
+
+ pack_bits(&addr, &pos, UBIFS_LPT_PNODE, UBIFS_LPT_TYPE_BITS);
+ if (c->big_lpt)
+ pack_bits(&addr, &pos, pnode->num, c->pcnt_bits);
+ for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+ pack_bits(&addr, &pos, pnode->lprops[i].free >> 3,
+ c->space_bits);
+ pack_bits(&addr, &pos, pnode->lprops[i].dirty >> 3,
+ c->space_bits);
+ if (pnode->lprops[i].flags & LPROPS_INDEX)
+ pack_bits(&addr, &pos, 1, 1);
+ else
+ pack_bits(&addr, &pos, 0, 1);
+ }
+ crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
+ c->pnode_sz - UBIFS_LPT_CRC_BYTES);
+ addr = buf;
+ pos = 0;
+ pack_bits(&addr, &pos, crc, UBIFS_LPT_CRC_BITS);
+}
+
+/**
+ * pack_nnode - pack all the bit fields of a nnode.
+ * @c: UBIFS file-system description object
+ * @buf: buffer into which to pack
+ * @nnode: nnode to pack
+ */
+static void pack_nnode(struct ubifs_info *c, void *buf,
+ struct ubifs_nnode *nnode)
+{
+ uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
+ int i, pos = 0;
+ uint16_t crc;
+
+ pack_bits(&addr, &pos, UBIFS_LPT_NNODE, UBIFS_LPT_TYPE_BITS);
+ if (c->big_lpt)
+ pack_bits(&addr, &pos, nnode->num, c->pcnt_bits);
+ for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+ int lnum = nnode->nbranch[i].lnum;
+
+ if (lnum == 0)
+ lnum = c->lpt_last + 1;
+ pack_bits(&addr, &pos, lnum - c->lpt_first, c->lpt_lnum_bits);
+ pack_bits(&addr, &pos, nnode->nbranch[i].offs,
+ c->lpt_offs_bits);
+ }
+ crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
+ c->nnode_sz - UBIFS_LPT_CRC_BYTES);
+ addr = buf;
+ pos = 0;
+ pack_bits(&addr, &pos, crc, UBIFS_LPT_CRC_BITS);
+}
+
+/**
+ * pack_ltab - pack the LPT's own lprops table.
+ * @c: UBIFS file-system description object
+ * @buf: buffer into which to pack
+ * @ltab: LPT's own lprops table to pack
+ */
+static void pack_ltab(struct ubifs_info *c, void *buf,
+ struct ubifs_lpt_lprops *ltab)
+{
+ uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
+ int i, pos = 0;
+ uint16_t crc;
+
+ pack_bits(&addr, &pos, UBIFS_LPT_LTAB, UBIFS_LPT_TYPE_BITS);
+ for (i = 0; i < c->lpt_lebs; i++) {
+ pack_bits(&addr, &pos, ltab[i].free, c->lpt_spc_bits);
+ pack_bits(&addr, &pos, ltab[i].dirty, c->lpt_spc_bits);
+ }
+ crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
+ c->ltab_sz - UBIFS_LPT_CRC_BYTES);
+ addr = buf;
+ pos = 0;
+ pack_bits(&addr, &pos, crc, UBIFS_LPT_CRC_BITS);
+}
+
+/**
+ * pack_lsave - pack the LPT's save table.
+ * @c: UBIFS file-system description object
+ * @buf: buffer into which to pack
+ * @lsave: LPT's save table to pack
+ */
+static void pack_lsave(struct ubifs_info *c, void *buf, int *lsave)
+{
+ uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
+ int i, pos = 0;
+ uint16_t crc;
+
+ pack_bits(&addr, &pos, UBIFS_LPT_LSAVE, UBIFS_LPT_TYPE_BITS);
+ for (i = 0; i < c->lsave_cnt; i++)
+ pack_bits(&addr, &pos, lsave[i], c->lnum_bits);
+ crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
+ c->lsave_sz - UBIFS_LPT_CRC_BYTES);
+ addr = buf;
+ pos = 0;
+ pack_bits(&addr, &pos, crc, UBIFS_LPT_CRC_BITS);
+}
+
+/**
+ * set_ltab - set LPT LEB properties.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number
+ * @free: amount of free space
+ * @dirty: amount of dirty space
+ */
+static void set_ltab(struct ubifs_info *c, int lnum, int free, int dirty)
+{
+ dbg_msg(3, "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);
+ c->ltab[lnum - c->lpt_first].free = free;
+ c->ltab[lnum - c->lpt_first].dirty = dirty;
+}
+
+/**
+ * calc_nnode_num - calculate nnode number.
+ * @row: the row in the tree (root is zero)
+ * @col: the column in the row (leftmost is zero)
+ *
+ * The nnode number is a number that uniquely identifies a nnode and can be used
+ * easily to traverse the tree from the root to that nnode.
+ *
+ * This function calculates and returns the nnode number for the nnode at @row
+ * and @col.
+ */
+static int calc_nnode_num(int row, int col)
+{
+ int num, bits;
+
+ num = 1;
+ while (row--) {
+ bits = (col & (UBIFS_LPT_FANOUT - 1));
+ col >>= UBIFS_LPT_FANOUT_SHIFT;
+ num <<= UBIFS_LPT_FANOUT_SHIFT;
+ num |= bits;
+ }
+ return num;
+}
+
+/**
+ * create_lpt - create LPT.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int create_lpt(struct ubifs_info *c)
+{
+ int lnum, err = 0, i, j, cnt, len, alen, row;
+ int blnum, boffs, bsz, bcnt;
+ struct ubifs_pnode *pnode = NULL;
+ struct ubifs_nnode *nnode = NULL;
+ void *buf = NULL, *p;
+ int *lsave = NULL;
+
+ pnode = malloc(sizeof(struct ubifs_pnode));
+ nnode = malloc(sizeof(struct ubifs_nnode));
+ buf = malloc(c->leb_size);
+ lsave = malloc(sizeof(int) * c->lsave_cnt);
+ if (!pnode || !nnode || !buf || !lsave) {
+ err = -ENOMEM;
+ goto out;
+ }
+ memset(pnode, 0 , sizeof(struct ubifs_pnode));
+ memset(nnode, 0 , sizeof(struct ubifs_pnode));
+
+ c->lscan_lnum = c->main_first;
+
+ lnum = c->lpt_first;
+ p = buf;
+ len = 0;
+ /* Number of leaf nodes (pnodes) */
+ cnt = (c->main_lebs + UBIFS_LPT_FANOUT - 1) >> UBIFS_LPT_FANOUT_SHIFT;
+ //printf("pnode_cnt=%d\n",cnt);
+
+ /*
+ * To calculate the internal node branches, we keep information about
+ * the level below.
+ */
+ blnum = lnum; /* LEB number of level below */
+ boffs = 0; /* Offset of level below */
+ bcnt = cnt; /* Number of nodes in level below */
+ bsz = c->pnode_sz; /* Size of nodes in level below */
+
+ /* Add pnodes */
+ for (i = 0; i < cnt; i++) {
+ if (len + c->pnode_sz > c->leb_size) {
+ alen = ALIGN(len, c->min_io_size);
+ set_ltab(c, lnum, c->leb_size - alen, alen - len);
+ memset(p, 0xff, alen - len);
+ err = write_leb(lnum++, alen, buf);
+ if (err)
+ goto out;
+ p = buf;
+ len = 0;
+ }
+ /* Fill in the pnode */
+ for (j = 0; j < UBIFS_LPT_FANOUT; j++) {
+ int k = (i << UBIFS_LPT_FANOUT_SHIFT) + j;
+
+ if (k < c->main_lebs)
+ pnode->lprops[j] = c->lpt[k];
+ else {
+ pnode->lprops[j].free = c->leb_size;
+ pnode->lprops[j].dirty = 0;
+ pnode->lprops[j].flags = 0;
+ }
+ }
+ pack_pnode(c, p, pnode);
+ p += c->pnode_sz;
+ len += c->pnode_sz;
+ /*
+ * pnodes are simply numbered left to right starting at zero,
+ * which means the pnode number can be used easily to traverse
+ * down the tree to the corresponding pnode.
+ */
+ pnode->num += 1;
+ }
+
+ row = c->lpt_hght - 1;
+ /* Add all nnodes, one level at a time */
+ while (1) {
+ /* Number of internal nodes (nnodes) at next level */
+ cnt = (cnt + UBIFS_LPT_FANOUT - 1) / UBIFS_LPT_FANOUT;
+ if (cnt == 0)
+ cnt = 1;
+ for (i = 0; i < cnt; i++) {
+ if (len + c->nnode_sz > c->leb_size) {
+ alen = ALIGN(len, c->min_io_size);
+ set_ltab(c, lnum, c->leb_size - alen,
+ alen - len);
+ memset(p, 0xff, alen - len);
+ err = write_leb(lnum++, alen, buf);
+ if (err)
+ goto out;
+ p = buf;
+ len = 0;
+ }
+ /* The root is on row zero */
+ if (row == 0) {
+ c->lpt_lnum = lnum;
+ c->lpt_offs = len;
+ }
+ /* Set branches to the level below */
+ for (j = 0; j < UBIFS_LPT_FANOUT; j++) {
+ if (bcnt) {
+ if (boffs + bsz > c->leb_size) {
+ blnum += 1;
+ boffs = 0;
+ }
+ nnode->nbranch[j].lnum = blnum;
+ nnode->nbranch[j].offs = boffs;
+ boffs += bsz;
+ bcnt--;
+ } else {
+ nnode->nbranch[j].lnum = 0;
+ nnode->nbranch[j].offs = 0;
+ }
+ }
+ nnode->num = calc_nnode_num(row, i);
+ pack_nnode(c, p, nnode);
+ p += c->nnode_sz;
+ len += c->nnode_sz;
+ }
+ /* Row zero is the top row */
+ if (row == 0)
+ break;
+ /* Update the information about the level below */
+ bcnt = cnt;
+ bsz = c->nnode_sz;
+ row -= 1;
+ }
+
+ if (c->big_lpt) {
+ /* Need to add LPT's save table */
+ if (len + c->lsave_sz > c->leb_size) {
+ alen = ALIGN(len, c->min_io_size);
+ set_ltab(c, lnum, c->leb_size - alen, alen - len);
+ memset(p, 0xff, alen - len);
+ err = write_leb(lnum++, alen, buf);
+ if (err)
+ goto out;
+ p = buf;
+ len = 0;
+ }
+
+ c->lsave_lnum = lnum;
+ c->lsave_offs = len;
+
+ for (i = 0; i < c->lsave_cnt; i++)
+ lsave[i] = c->main_first + i;
+
+ pack_lsave(c, p, lsave);
+ p += c->lsave_sz;
+ len += c->lsave_sz;
+ }
+
+ /* Need to add LPT's own LEB properties table */
+ if (len + c->ltab_sz > c->leb_size) {
+ alen = ALIGN(len, c->min_io_size);
+ set_ltab(c, lnum, c->leb_size - alen, alen - len);
+ memset(p, 0xff, alen - len);
+ err = write_leb(lnum++, alen, buf);
+ if (err)
+ goto out;
+ p = buf;
+ len = 0;
+ }
+
+ c->ltab_lnum = lnum;
+ c->ltab_offs = len;
+
+ /* Update ltab before packing it */
+ len += c->ltab_sz;
+ alen = ALIGN(len, c->min_io_size);
+ set_ltab(c, lnum, c->leb_size - alen, alen - len);
+
+ pack_ltab(c, p, c->ltab);
+ p += c->ltab_sz;
+
+ /* Write remaining buffer */
+ memset(p, 0xff, alen - len);
+ err = write_leb(lnum, alen, buf);
+ if (err)
+ goto out;
+
+ c->nhead_lnum = lnum;
+ c->nhead_offs = ALIGN(len, c->min_io_size);
+
+ dbg_msg(1, "space_bits: %d", c->space_bits);
+ dbg_msg(1, "lpt_lnum_bits: %d", c->lpt_lnum_bits);
+ dbg_msg(1, "lpt_offs_bits: %d", c->lpt_offs_bits);
+ dbg_msg(1, "lpt_spc_bits: %d", c->lpt_spc_bits);
+ dbg_msg(1, "pcnt_bits: %d", c->pcnt_bits);
+ dbg_msg(1, "lnum_bits: %d", c->lnum_bits);
+ dbg_msg(1, "pnode_sz: %d", c->pnode_sz);
+ dbg_msg(1, "nnode_sz: %d", c->nnode_sz);
+ dbg_msg(1, "ltab_sz: %d", c->ltab_sz);
+ dbg_msg(1, "lsave_sz: %d", c->lsave_sz);
+ dbg_msg(1, "lsave_cnt: %d", c->lsave_cnt);
+ dbg_msg(1, "lpt_hght: %d", c->lpt_hght);
+ dbg_msg(1, "big_lpt: %d", c->big_lpt);
+ dbg_msg(1, "LPT root is at %d:%d", c->lpt_lnum, c->lpt_offs);
+ dbg_msg(1, "LPT head is at %d:%d", c->nhead_lnum, c->nhead_offs);
+ dbg_msg(1, "LPT ltab is at %d:%d", c->ltab_lnum, c->ltab_offs);
+ if (c->big_lpt)
+ dbg_msg(1, "LPT lsave is at %d:%d",
+ c->lsave_lnum, c->lsave_offs);
+out:
+ free(lsave);
+ free(buf);
+ free(nnode);
+ free(pnode);
+ return err;
+}