diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/crc32.c | 95 | ||||
| -rw-r--r-- | lib/fec.c | 904 | ||||
| -rw-r--r-- | lib/libmtd.c | 1157 | ||||
| -rw-r--r-- | lib/libmtd_int.h | 88 | ||||
| -rw-r--r-- | lib/libmtd_legacy.c | 359 |
5 files changed, 2603 insertions, 0 deletions
diff --git a/lib/crc32.c b/lib/crc32.c new file mode 100644 index 0000000..6b1e50c --- /dev/null +++ b/lib/crc32.c @@ -0,0 +1,95 @@ +/* + * COPYRIGHT (C) 1986 Gary S. Brown. You may use this program, or + * code or tables extracted from it, as desired without restriction. + * + * First, the polynomial itself and its table of feedback terms. The + * polynomial is + * X^32+X^26+X^23+X^22+X^16+X^12+X^11+X^10+X^8+X^7+X^5+X^4+X^2+X^1+X^0 + * + * Note that we take it "backwards" and put the highest-order term in + * the lowest-order bit. The X^32 term is "implied"; the LSB is the + * X^31 term, etc. The X^0 term (usually shown as "+1") results in + * the MSB being 1 + * + * Note that the usual hardware shift register implementation, which + * is what we're using (we're merely optimizing it by doing eight-bit + * chunks at a time) shifts bits into the lowest-order term. In our + * implementation, that means shifting towards the right. Why do we + * do it this way? Because the calculated CRC must be transmitted in + * order from highest-order term to lowest-order term. UARTs transmit + * characters in order from LSB to MSB. By storing the CRC this way + * we hand it to the UART in the order low-byte to high-byte; the UART + * sends each low-bit to hight-bit; and the result is transmission bit + * by bit from highest- to lowest-order term without requiring any bit + * shuffling on our part. Reception works similarly + * + * The feedback terms table consists of 256, 32-bit entries. Notes + * + * The table can be generated at runtime if desired; code to do so + * is shown later. It might not be obvious, but the feedback + * terms simply represent the results of eight shift/xor opera + * tions for all combinations of data and CRC register values + * + * The values must be right-shifted by eight bits by the "updcrc + * logic; the shift must be unsigned (bring in zeroes). On some + * hardware you could probably optimize the shift in assembler by + * using byte-swap instructions + * polynomial $edb88320 + */ + +#include <stdint.h> + +const uint32_t crc32_table[256] = { + 0x00000000L, 0x77073096L, 0xee0e612cL, 0x990951baL, 0x076dc419L, + 0x706af48fL, 0xe963a535L, 0x9e6495a3L, 0x0edb8832L, 0x79dcb8a4L, + 0xe0d5e91eL, 0x97d2d988L, 0x09b64c2bL, 0x7eb17cbdL, 0xe7b82d07L, + 0x90bf1d91L, 0x1db71064L, 0x6ab020f2L, 0xf3b97148L, 0x84be41deL, + 0x1adad47dL, 0x6ddde4ebL, 0xf4d4b551L, 0x83d385c7L, 0x136c9856L, + 0x646ba8c0L, 0xfd62f97aL, 0x8a65c9ecL, 0x14015c4fL, 0x63066cd9L, + 0xfa0f3d63L, 0x8d080df5L, 0x3b6e20c8L, 0x4c69105eL, 0xd56041e4L, + 0xa2677172L, 0x3c03e4d1L, 0x4b04d447L, 0xd20d85fdL, 0xa50ab56bL, + 0x35b5a8faL, 0x42b2986cL, 0xdbbbc9d6L, 0xacbcf940L, 0x32d86ce3L, + 0x45df5c75L, 0xdcd60dcfL, 0xabd13d59L, 0x26d930acL, 0x51de003aL, + 0xc8d75180L, 0xbfd06116L, 0x21b4f4b5L, 0x56b3c423L, 0xcfba9599L, + 0xb8bda50fL, 0x2802b89eL, 0x5f058808L, 0xc60cd9b2L, 0xb10be924L, + 0x2f6f7c87L, 0x58684c11L, 0xc1611dabL, 0xb6662d3dL, 0x76dc4190L, + 0x01db7106L, 0x98d220bcL, 0xefd5102aL, 0x71b18589L, 0x06b6b51fL, + 0x9fbfe4a5L, 0xe8b8d433L, 0x7807c9a2L, 0x0f00f934L, 0x9609a88eL, + 0xe10e9818L, 0x7f6a0dbbL, 0x086d3d2dL, 0x91646c97L, 0xe6635c01L, + 0x6b6b51f4L, 0x1c6c6162L, 0x856530d8L, 0xf262004eL, 0x6c0695edL, + 0x1b01a57bL, 0x8208f4c1L, 0xf50fc457L, 0x65b0d9c6L, 0x12b7e950L, + 0x8bbeb8eaL, 0xfcb9887cL, 0x62dd1ddfL, 0x15da2d49L, 0x8cd37cf3L, + 0xfbd44c65L, 0x4db26158L, 0x3ab551ceL, 0xa3bc0074L, 0xd4bb30e2L, + 0x4adfa541L, 0x3dd895d7L, 0xa4d1c46dL, 0xd3d6f4fbL, 0x4369e96aL, + 0x346ed9fcL, 0xad678846L, 0xda60b8d0L, 0x44042d73L, 0x33031de5L, + 0xaa0a4c5fL, 0xdd0d7cc9L, 0x5005713cL, 0x270241aaL, 0xbe0b1010L, + 0xc90c2086L, 0x5768b525L, 0x206f85b3L, 0xb966d409L, 0xce61e49fL, + 0x5edef90eL, 0x29d9c998L, 0xb0d09822L, 0xc7d7a8b4L, 0x59b33d17L, + 0x2eb40d81L, 0xb7bd5c3bL, 0xc0ba6cadL, 0xedb88320L, 0x9abfb3b6L, + 0x03b6e20cL, 0x74b1d29aL, 0xead54739L, 0x9dd277afL, 0x04db2615L, + 0x73dc1683L, 0xe3630b12L, 0x94643b84L, 0x0d6d6a3eL, 0x7a6a5aa8L, + 0xe40ecf0bL, 0x9309ff9dL, 0x0a00ae27L, 0x7d079eb1L, 0xf00f9344L, + 0x8708a3d2L, 0x1e01f268L, 0x6906c2feL, 0xf762575dL, 0x806567cbL, + 0x196c3671L, 0x6e6b06e7L, 0xfed41b76L, 0x89d32be0L, 0x10da7a5aL, + 0x67dd4accL, 0xf9b9df6fL, 0x8ebeeff9L, 0x17b7be43L, 0x60b08ed5L, + 0xd6d6a3e8L, 0xa1d1937eL, 0x38d8c2c4L, 0x4fdff252L, 0xd1bb67f1L, + 0xa6bc5767L, 0x3fb506ddL, 0x48b2364bL, 0xd80d2bdaL, 0xaf0a1b4cL, + 0x36034af6L, 0x41047a60L, 0xdf60efc3L, 0xa867df55L, 0x316e8eefL, + 0x4669be79L, 0xcb61b38cL, 0xbc66831aL, 0x256fd2a0L, 0x5268e236L, + 0xcc0c7795L, 0xbb0b4703L, 0x220216b9L, 0x5505262fL, 0xc5ba3bbeL, + 0xb2bd0b28L, 0x2bb45a92L, 0x5cb36a04L, 0xc2d7ffa7L, 0xb5d0cf31L, + 0x2cd99e8bL, 0x5bdeae1dL, 0x9b64c2b0L, 0xec63f226L, 0x756aa39cL, + 0x026d930aL, 0x9c0906a9L, 0xeb0e363fL, 0x72076785L, 0x05005713L, + 0x95bf4a82L, 0xe2b87a14L, 0x7bb12baeL, 0x0cb61b38L, 0x92d28e9bL, + 0xe5d5be0dL, 0x7cdcefb7L, 0x0bdbdf21L, 0x86d3d2d4L, 0xf1d4e242L, + 0x68ddb3f8L, 0x1fda836eL, 0x81be16cdL, 0xf6b9265bL, 0x6fb077e1L, + 0x18b74777L, 0x88085ae6L, 0xff0f6a70L, 0x66063bcaL, 0x11010b5cL, + 0x8f659effL, 0xf862ae69L, 0x616bffd3L, 0x166ccf45L, 0xa00ae278L, + 0xd70dd2eeL, 0x4e048354L, 0x3903b3c2L, 0xa7672661L, 0xd06016f7L, + 0x4969474dL, 0x3e6e77dbL, 0xaed16a4aL, 0xd9d65adcL, 0x40df0b66L, + 0x37d83bf0L, 0xa9bcae53L, 0xdebb9ec5L, 0x47b2cf7fL, 0x30b5ffe9L, + 0xbdbdf21cL, 0xcabac28aL, 0x53b39330L, 0x24b4a3a6L, 0xbad03605L, + 0xcdd70693L, 0x54de5729L, 0x23d967bfL, 0xb3667a2eL, 0xc4614ab8L, + 0x5d681b02L, 0x2a6f2b94L, 0xb40bbe37L, 0xc30c8ea1L, 0x5a05df1bL, + 0x2d02ef8dL +}; diff --git a/lib/fec.c b/lib/fec.c new file mode 100644 index 0000000..6d9020f --- /dev/null +++ b/lib/fec.c @@ -0,0 +1,904 @@ +/* + * fec.c -- forward error correction based on Vandermonde matrices + * 980624 + * (C) 1997-98 Luigi Rizzo (luigi@iet.unipi.it) + * + * Portions derived from code by Phil Karn (karn@ka9q.ampr.org), + * Robert Morelos-Zaragoza (robert@spectra.eng.hawaii.edu) and Hari + * Thirumoorthy (harit@spectra.eng.hawaii.edu), Aug 1995 + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials + * provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, + * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A + * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS + * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, + * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, + * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, + * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR + * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT + * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY + * OF SUCH DAMAGE. + */ + +/* + * The following parameter defines how many bits are used for + * field elements. The code supports any value from 2 to 16 + * but fastest operation is achieved with 8 bit elements + * This is the only parameter you may want to change. + */ +#ifndef GF_BITS +#define GF_BITS 8 /* code over GF(2**GF_BITS) - change to suit */ +#endif + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +/* + * stuff used for testing purposes only + */ + +#ifdef TEST +#define DEB(x) +#define DDB(x) x +#define DEBUG 0 /* minimal debugging */ +#ifdef MSDOS +#include <time.h> +struct timeval { + unsigned long ticks; +}; +#define gettimeofday(x, dummy) { (x)->ticks = clock() ; } +#define DIFF_T(a,b) (1+ 1000000*(a.ticks - b.ticks) / CLOCKS_PER_SEC ) +typedef unsigned long u_long ; +typedef unsigned short u_short ; +#else /* typically, unix systems */ +#include <sys/time.h> +#define DIFF_T(a,b) \ + (1+ 1000000*(a.tv_sec - b.tv_sec) + (a.tv_usec - b.tv_usec) ) +#endif + +#define TICK(t) \ + {struct timeval x ; \ + gettimeofday(&x, NULL) ; \ + t = x.tv_usec + 1000000* (x.tv_sec & 0xff ) ; \ + } +#define TOCK(t) \ + { u_long t1 ; TICK(t1) ; \ + if (t1 < t) t = 256000000 + t1 - t ; \ + else t = t1 - t ; \ + if (t == 0) t = 1 ;} + +u_long ticks[10]; /* vars for timekeeping */ +#else +#define DEB(x) +#define DDB(x) +#define TICK(x) +#define TOCK(x) +#endif /* TEST */ + +/* + * You should not need to change anything beyond this point. + * The first part of the file implements linear algebra in GF. + * + * gf is the type used to store an element of the Galois Field. + * Must constain at least GF_BITS bits. + * + * Note: unsigned char will work up to GF(256) but int seems to run + * faster on the Pentium. We use int whenever have to deal with an + * index, since they are generally faster. + */ +#if (GF_BITS < 2 && GF_BITS >16) +#error "GF_BITS must be 2 .. 16" +#endif +#if (GF_BITS <= 8) +typedef unsigned char gf; +#else +typedef unsigned short gf; +#endif + +#define GF_SIZE ((1 << GF_BITS) - 1) /* powers of \alpha */ + +/* + * Primitive polynomials - see Lin & Costello, Appendix A, + * and Lee & Messerschmitt, p. 453. + */ +static char *allPp[] = { /* GF_BITS polynomial */ + NULL, /* 0 no code */ + NULL, /* 1 no code */ + "111", /* 2 1+x+x^2 */ + "1101", /* 3 1+x+x^3 */ + "11001", /* 4 1+x+x^4 */ + "101001", /* 5 1+x^2+x^5 */ + "1100001", /* 6 1+x+x^6 */ + "10010001", /* 7 1 + x^3 + x^7 */ + "101110001", /* 8 1+x^2+x^3+x^4+x^8 */ + "1000100001", /* 9 1+x^4+x^9 */ + "10010000001", /* 10 1+x^3+x^10 */ + "101000000001", /* 11 1+x^2+x^11 */ + "1100101000001", /* 12 1+x+x^4+x^6+x^12 */ + "11011000000001", /* 13 1+x+x^3+x^4+x^13 */ + "110000100010001", /* 14 1+x+x^6+x^10+x^14 */ + "1100000000000001", /* 15 1+x+x^15 */ + "11010000000010001" /* 16 1+x+x^3+x^12+x^16 */ +}; + + +/* + * To speed up computations, we have tables for logarithm, exponent + * and inverse of a number. If GF_BITS <= 8, we use a table for + * multiplication as well (it takes 64K, no big deal even on a PDA, + * especially because it can be pre-initialized an put into a ROM!), + * otherwhise we use a table of logarithms. + * In any case the macro gf_mul(x,y) takes care of multiplications. + */ + +static gf gf_exp[2*GF_SIZE]; /* index->poly form conversion table */ +static int gf_log[GF_SIZE + 1]; /* Poly->index form conversion table */ +static gf inverse[GF_SIZE+1]; /* inverse of field elem. */ + /* inv[\alpha**i]=\alpha**(GF_SIZE-i-1) */ + +/* + * modnn(x) computes x % GF_SIZE, where GF_SIZE is 2**GF_BITS - 1, + * without a slow divide. + */ +static inline gf +modnn(int x) +{ + while (x >= GF_SIZE) { + x -= GF_SIZE; + x = (x >> GF_BITS) + (x & GF_SIZE); + } + return x; +} + +#define SWAP(a,b,t) {t tmp; tmp=a; a=b; b=tmp;} + +/* + * gf_mul(x,y) multiplies two numbers. If GF_BITS<=8, it is much + * faster to use a multiplication table. + * + * USE_GF_MULC, GF_MULC0(c) and GF_ADDMULC(x) can be used when multiplying + * many numbers by the same constant. In this case the first + * call sets the constant, and others perform the multiplications. + * A value related to the multiplication is held in a local variable + * declared with USE_GF_MULC . See usage in addmul1(). + */ +#if (GF_BITS <= 8) +static gf gf_mul_table[GF_SIZE + 1][GF_SIZE + 1]; + +#define gf_mul(x,y) gf_mul_table[x][y] + +#define USE_GF_MULC register gf * __gf_mulc_ +#define GF_MULC0(c) __gf_mulc_ = gf_mul_table[c] +#define GF_ADDMULC(dst, x) dst ^= __gf_mulc_[x] + +static void +init_mul_table() +{ + int i, j; + for (i=0; i< GF_SIZE+1; i++) + for (j=0; j< GF_SIZE+1; j++) + gf_mul_table[i][j] = gf_exp[modnn(gf_log[i] + gf_log[j]) ] ; + + for (j=0; j< GF_SIZE+1; j++) + gf_mul_table[0][j] = gf_mul_table[j][0] = 0; +} +#else /* GF_BITS > 8 */ +static inline gf +gf_mul(x,y) +{ + if ( (x) == 0 || (y)==0 ) return 0; + + return gf_exp[gf_log[x] + gf_log[y] ] ; +} +#define init_mul_table() + +#define USE_GF_MULC register gf * __gf_mulc_ +#define GF_MULC0(c) __gf_mulc_ = &gf_exp[ gf_log[c] ] +#define GF_ADDMULC(dst, x) { if (x) dst ^= __gf_mulc_[ gf_log[x] ] ; } +#endif + +/* + * Generate GF(2**m) from the irreducible polynomial p(X) in p[0]..p[m] + * Lookup tables: + * index->polynomial form gf_exp[] contains j= \alpha^i; + * polynomial form -> index form gf_log[ j = \alpha^i ] = i + * \alpha=x is the primitive element of GF(2^m) + * + * For efficiency, gf_exp[] has size 2*GF_SIZE, so that a simple + * multiplication of two numbers can be resolved without calling modnn + */ + +/* + * i use malloc so many times, it is easier to put checks all in + * one place. + */ +static void * +my_malloc(int sz, char *err_string) +{ + void *p = malloc( sz ); + if (p == NULL) { + fprintf(stderr, "-- malloc failure allocating %s\n", err_string); + exit(1) ; + } + return p ; +} + +#define NEW_GF_MATRIX(rows, cols) \ + (gf *)my_malloc(rows * cols * sizeof(gf), " ## __LINE__ ## " ) + +/* + * initialize the data structures used for computations in GF. + */ +static void +generate_gf(void) +{ + int i; + gf mask; + char *Pp = allPp[GF_BITS] ; + + mask = 1; /* x ** 0 = 1 */ + gf_exp[GF_BITS] = 0; /* will be updated at the end of the 1st loop */ + /* + * first, generate the (polynomial representation of) powers of \alpha, + * which are stored in gf_exp[i] = \alpha ** i . + * At the same time build gf_log[gf_exp[i]] = i . + * The first GF_BITS powers are simply bits shifted to the left. + */ + for (i = 0; i < GF_BITS; i++, mask <<= 1 ) { + gf_exp[i] = mask; + gf_log[gf_exp[i]] = i; + /* + * If Pp[i] == 1 then \alpha ** i occurs in poly-repr + * gf_exp[GF_BITS] = \alpha ** GF_BITS + */ + if ( Pp[i] == '1' ) + gf_exp[GF_BITS] ^= mask; + } + /* + * now gf_exp[GF_BITS] = \alpha ** GF_BITS is complete, so can als + * compute its inverse. + */ + gf_log[gf_exp[GF_BITS]] = GF_BITS; + /* + * Poly-repr of \alpha ** (i+1) is given by poly-repr of + * \alpha ** i shifted left one-bit and accounting for any + * \alpha ** GF_BITS term that may occur when poly-repr of + * \alpha ** i is shifted. + */ + mask = 1 << (GF_BITS - 1 ) ; + for (i = GF_BITS + 1; i < GF_SIZE; i++) { + if (gf_exp[i - 1] >= mask) + gf_exp[i] = gf_exp[GF_BITS] ^ ((gf_exp[i - 1] ^ mask) << 1); + else + gf_exp[i] = gf_exp[i - 1] << 1; + gf_log[gf_exp[i]] = i; + } + /* + * log(0) is not defined, so use a special value + */ + gf_log[0] = GF_SIZE ; + /* set the extended gf_exp values for fast multiply */ + for (i = 0 ; i < GF_SIZE ; i++) + gf_exp[i + GF_SIZE] = gf_exp[i] ; + + /* + * again special cases. 0 has no inverse. This used to + * be initialized to GF_SIZE, but it should make no difference + * since noone is supposed to read from here. + */ + inverse[0] = 0 ; + inverse[1] = 1; + for (i=2; i<=GF_SIZE; i++) + inverse[i] = gf_exp[GF_SIZE-gf_log[i]]; +} + +/* + * Various linear algebra operations that i use often. + */ + +/* + * addmul() computes dst[] = dst[] + c * src[] + * This is used often, so better optimize it! Currently the loop is + * unrolled 16 times, a good value for 486 and pentium-class machines. + * The case c=0 is also optimized, whereas c=1 is not. These + * calls are unfrequent in my typical apps so I did not bother. + * + * Note that gcc on + */ +#define addmul(dst, src, c, sz) \ + if (c != 0) addmul1(dst, src, c, sz) + +#define UNROLL 16 /* 1, 4, 8, 16 */ +static void +addmul1(gf *dst1, gf *src1, gf c, int sz) +{ + USE_GF_MULC ; + register gf *dst = dst1, *src = src1 ; + gf *lim = &dst[sz - UNROLL + 1] ; + + GF_MULC0(c) ; + +#if (UNROLL > 1) /* unrolling by 8/16 is quite effective on the pentium */ + for (; dst < lim ; dst += UNROLL, src += UNROLL ) { + GF_ADDMULC( dst[0] , src[0] ); + GF_ADDMULC( dst[1] , src[1] ); + GF_ADDMULC( dst[2] , src[2] ); + GF_ADDMULC( dst[3] , src[3] ); +#if (UNROLL > 4) + GF_ADDMULC( dst[4] , src[4] ); + GF_ADDMULC( dst[5] , src[5] ); + GF_ADDMULC( dst[6] , src[6] ); + GF_ADDMULC( dst[7] , src[7] ); +#endif +#if (UNROLL > 8) + GF_ADDMULC( dst[8] , src[8] ); + GF_ADDMULC( dst[9] , src[9] ); + GF_ADDMULC( dst[10] , src[10] ); + GF_ADDMULC( dst[11] , src[11] ); + GF_ADDMULC( dst[12] , src[12] ); + GF_ADDMULC( dst[13] , src[13] ); + GF_ADDMULC( dst[14] , src[14] ); + GF_ADDMULC( dst[15] , src[15] ); +#endif + } +#endif + lim += UNROLL - 1 ; + for (; dst < lim; dst++, src++ ) /* final components */ + GF_ADDMULC( *dst , *src ); +} + +/* + * computes C = AB where A is n*k, B is k*m, C is n*m + */ +static void +matmul(gf *a, gf *b, gf *c, int n, int k, int m) +{ + int row, col, i ; + + for (row = 0; row < n ; row++) { + for (col = 0; col < m ; col++) { + gf *pa = &a[ row * k ]; + gf *pb = &b[ col ]; + gf acc = 0 ; + for (i = 0; i < k ; i++, pa++, pb += m ) + acc ^= gf_mul( *pa, *pb ) ; + c[ row * m + col ] = acc ; + } + } +} + +#ifdef DEBUG +/* + * returns 1 if the square matrix is identiy + * (only for test) + */ +static int +is_identity(gf *m, int k) +{ + int row, col ; + for (row=0; row<k; row++) + for (col=0; col<k; col++) + if ( (row==col && *m != 1) || + (row!=col && *m != 0) ) + return 0 ; + else + m++ ; + return 1 ; +} +#endif /* debug */ + +/* + * invert_mat() takes a matrix and produces its inverse + * k is the size of the matrix. + * (Gauss-Jordan, adapted from Numerical Recipes in C) + * Return non-zero if singular. + */ +DEB( int pivloops=0; int pivswaps=0 ; /* diagnostic */) +static int +invert_mat(gf *src, int k) +{ + gf c, *p ; + int irow, icol, row, col, i, ix ; + + int error = 1 ; + int *indxc = my_malloc(k*sizeof(int), "indxc"); + int *indxr = my_malloc(k*sizeof(int), "indxr"); + int *ipiv = my_malloc(k*sizeof(int), "ipiv"); + gf *id_row = NEW_GF_MATRIX(1, k); + gf *temp_row = NEW_GF_MATRIX(1, k); + + memset(id_row, '\0', k*sizeof(gf)); + DEB( pivloops=0; pivswaps=0 ; /* diagnostic */ ) + /* + * ipiv marks elements already used as pivots. + */ + for (i = 0; i < k ; i++) + ipiv[i] = 0 ; + + for (col = 0; col < k ; col++) { + gf *pivot_row ; + /* + * Zeroing column 'col', look for a non-zero element. + * First try on the diagonal, if it fails, look elsewhere. + */ + irow = icol = -1 ; + if (ipiv[col] != 1 && src[col*k + col] != 0) { + irow = col ; + icol = col ; + goto found_piv ; + } + for (row = 0 ; row < k ; row++) { + if (ipiv[row] != 1) { + for (ix = 0 ; ix < k ; ix++) { + DEB( pivloops++ ; ) + if (ipiv[ix] == 0) { + if (src[row*k + ix] != 0) { + irow = row ; + icol = ix ; + goto found_piv ; + } + } else if (ipiv[ix] > 1) { + fprintf(stderr, "singular matrix\n"); + goto fail ; + } + } + } + } + if (icol == -1) { + fprintf(stderr, "XXX pivot not found!\n"); + goto fail ; + } +found_piv: + ++(ipiv[icol]) ; + /* + * swap rows irow and icol, so afterwards the diagonal + * element will be correct. Rarely done, not worth + * optimizing. + */ + if (irow != icol) { + for (ix = 0 ; ix < k ; ix++ ) { + SWAP( src[irow*k + ix], src[icol*k + ix], gf) ; + } + } + indxr[col] = irow ; + indxc[col] = icol ; + pivot_row = &src[icol*k] ; + c = pivot_row[icol] ; + if (c == 0) { + fprintf(stderr, "singular matrix 2\n"); + goto fail ; + } + if (c != 1 ) { /* otherwhise this is a NOP */ + /* + * this is done often , but optimizing is not so + * fruitful, at least in the obvious ways (unrolling) + */ + DEB( pivswaps++ ; ) + c = inverse[ c ] ; + pivot_row[icol] = 1 ; + for (ix = 0 ; ix < k ; ix++ ) + pivot_row[ix] = gf_mul(c, pivot_row[ix] ); + } + /* + * from all rows, remove multiples of the selected row + * to zero the relevant entry (in fact, the entry is not zero + * because we know it must be zero). + * (Here, if we know that the pivot_row is the identity, + * we can optimize the addmul). + */ + id_row[icol] = 1; + if (memcmp(pivot_row, id_row, k*sizeof(gf)) != 0) { + for (p = src, ix = 0 ; ix < k ; ix++, p += k ) { + if (ix != icol) { + c = p[icol] ; + p[icol] = 0 ; + addmul(p, pivot_row, c, k ); + } + } + } + id_row[icol] = 0; + } /* done all columns */ + for (col = k-1 ; col >= 0 ; col-- ) { + if (indxr[col] <0 || indxr[col] >= k) + fprintf(stderr, "AARGH, indxr[col] %d\n", indxr[col]); + else if (indxc[col] <0 || indxc[col] >= k) + fprintf(stderr, "AARGH, indxc[col] %d\n", indxc[col]); + else + if (indxr[col] != indxc[col] ) { + for (row = 0 ; row < k ; row++ ) { + SWAP( src[row*k + indxr[col]], src[row*k + indxc[col]], gf) ; + } + } + } + error = 0 ; +fail: + free(indxc); + free(indxr); + free(ipiv); + free(id_row); + free(temp_row); + return error ; +} + +/* + * fast code for inverting a vandermonde matrix. + * XXX NOTE: It assumes that the matrix + * is not singular and _IS_ a vandermonde matrix. Only uses + * the second column of the matrix, containing the p_i's. + * + * Algorithm borrowed from "Numerical recipes in C" -- sec.2.8, but + * largely revised for my purposes. + * p = coefficients of the matrix (p_i) + * q = values of the polynomial (known) + */ + +int +invert_vdm(gf *src, int k) +{ + int i, j, row, col ; + gf *b, *c, *p; + gf t, xx ; + + if (k == 1) /* degenerate case, matrix must be p^0 = 1 */ + return 0 ; + /* + * c holds the coefficient of P(x) = Prod (x - p_i), i=0..k-1 + * b holds the coefficient for the matrix inversion + */ + c = NEW_GF_MATRIX(1, k); + b = NEW_GF_MATRIX(1, k); + + p = NEW_GF_MATRIX(1, k); + + for ( j=1, i = 0 ; i < k ; i++, j+=k ) { + c[i] = 0 ; + p[i] = src[j] ; /* p[i] */ + } + /* + * construct coeffs. recursively. We know c[k] = 1 (implicit) + * and start P_0 = x - p_0, then at each stage multiply by + * x - p_i generating P_i = x P_{i-1} - p_i P_{i-1} + * After k steps we are done. + */ + c[k-1] = p[0] ; /* really -p(0), but x = -x in GF(2^m) */ + for (i = 1 ; i < k ; i++ ) { + gf p_i = p[i] ; /* see above comment */ + for (j = k-1 - ( i - 1 ) ; j < k-1 ; j++ ) + c[j] ^= gf_mul( p_i, c[j+1] ) ; + c[k-1] ^= p_i ; + } + + for (row = 0 ; row < k ; row++ ) { + /* + * synthetic division etc. + */ + xx = p[row] ; + t = 1 ; + b[k-1] = 1 ; /* this is in fact c[k] */ + for (i = k-2 ; i >= 0 ; i-- ) { + b[i] = c[i+1] ^ gf_mul(xx, b[i+1]) ; + t = gf_mul(xx, t) ^ b[i] ; + } + for (col = 0 ; col < k ; col++ ) + src[col*k + row] = gf_mul(inverse[t], b[col] ); + } + free(c) ; + free(b) ; + free(p) ; + return 0 ; +} + +static int fec_initialized = 0 ; +static void +init_fec() +{ + TICK(ticks[0]); + generate_gf(); + TOCK(ticks[0]); + DDB(fprintf(stderr, "generate_gf took %ldus\n", ticks[0]);) + TICK(ticks[0]); + init_mul_table(); + TOCK(ticks[0]); + DDB(fprintf(stderr, "init_mul_table took %ldus\n", ticks[0]);) + fec_initialized = 1 ; +} + +/* + * This section contains the proper FEC encoding/decoding routines. + * The encoding matrix is computed starting with a Vandermonde matrix, + * and then transforming it into a systematic matrix. + */ + +#define FEC_MAGIC 0xFECC0DEC + +struct fec_parms { + u_long magic ; + int k, n ; /* parameters of the code */ + gf *enc_matrix ; +} ; + +void +fec_free(struct fec_parms *p) +{ + if (p==NULL || + p->magic != ( ( (FEC_MAGIC ^ p->k) ^ p->n) ^ (int)(p->enc_matrix)) ) { + fprintf(stderr, "bad parameters to fec_free\n"); + return ; + } + free(p->enc_matrix); + free(p); +} + +/* + * create a new encoder, returning a descriptor. This contains k,n and + * the encoding matrix. + */ +struct fec_parms * +fec_new(int k, int n) +{ + int row, col ; + gf *p, *tmp_m ; + + struct fec_parms *retval ; + + if (fec_initialized == 0) + init_fec(); + + if (k > GF_SIZE + 1 || n > GF_SIZE + 1 || k > n ) { + fprintf(stderr, "Invalid parameters k %d n %d GF_SIZE %d\n", + k, n, GF_SIZE ); + return NULL ; + } + retval = my_malloc(sizeof(struct fec_parms), "new_code"); + retval->k = k ; + retval->n = n ; + retval->enc_matrix = NEW_GF_MATRIX(n, k); + retval->magic = ( ( FEC_MAGIC ^ k) ^ n) ^ (int)(retval->enc_matrix) ; + tmp_m = NEW_GF_MATRIX(n, k); + /* + * fill the matrix with powers of field elements, starting from 0. + * The first row is special, cannot be computed with exp. table. + */ + tmp_m[0] = 1 ; + for (col = 1; col < k ; col++) + tmp_m[col] = 0 ; + for (p = tmp_m + k, row = 0; row < n-1 ; row++, p += k) { + for ( col = 0 ; col < k ; col ++ ) + p[col] = gf_exp[modnn(row*col)]; + } + + /* + * quick code to build systematic matrix: invert the top + * k*k vandermonde matrix, multiply right the bottom n-k rows + * by the inverse, and construct the identity matrix at the top. + */ + TICK(ticks[3]); + invert_vdm(tmp_m, k); /* much faster than invert_mat */ + matmul(tmp_m + k*k, tmp_m, retval->enc_matrix + k*k, n - k, k, k); + /* + * the upper matrix is I so do not bother with a slow multiply + */ + memset(retval->enc_matrix, '\0', k*k*sizeof(gf) ); + for (p = retval->enc_matrix, col = 0 ; col < k ; col++, p += k+1 ) + *p = 1 ; + free(tmp_m); + TOCK(ticks[3]); + + DDB(fprintf(stderr, "--- %ld us to build encoding matrix\n", + ticks[3]);) + DEB(pr_matrix(retval->enc_matrix, n, k, "encoding_matrix");) + return retval ; +} + +/* + * fec_encode accepts as input pointers to n data packets of size sz, + * and produces as output a packet pointed to by fec, computed + * with index "index". + */ +void +fec_encode(struct fec_parms *code, gf *src[], gf *fec, int index, int sz) +{ + int i, k = code->k ; + gf *p ; + + if (GF_BITS > 8) + sz /= 2 ; + + if (index < k) + memcpy(fec, src[index], sz*sizeof(gf) ) ; + else if (index < code->n) { + p = &(code->enc_matrix[index*k] ); + memset(fec, '\0', sz*sizeof(gf)); + for (i = 0; i < k ; i++) + addmul(fec, src[i], p[i], sz ) ; + } else + fprintf(stderr, "Invalid index %d (max %d)\n", + index, code->n - 1 ); +} + +void fec_encode_linear(struct fec_parms *code, gf *src, gf *fec, int index, int sz) +{ + int i, k = code->k ; + gf *p ; + + if (GF_BITS > 8) + sz /= 2 ; + + if (index < k) + memcpy(fec, src + (index * sz), sz*sizeof(gf) ) ; + else if (index < code->n) { + p = &(code->enc_matrix[index*k] ); + memset(fec, '\0', sz*sizeof(gf)); + for (i = 0; i < k ; i++) + addmul(fec, src + (i * sz), p[i], sz ) ; + } else + fprintf(stderr, "Invalid index %d (max %d)\n", + index, code->n - 1 ); +} +/* + * shuffle move src packets in their position + */ +static int +shuffle(gf *pkt[], int index[], int k) +{ + int i; + + for ( i = 0 ; i < k ; ) { + if (index[i] >= k || index[i] == i) + i++ ; + else { + /* + * put pkt in the right position (first check for conflicts). + */ + int c = index[i] ; + + if (index[c] == c) { + DEB(fprintf(stderr, "\nshuffle, error at %d\n", i);) + return 1 ; + } + SWAP(index[i], index[c], int) ; + SWAP(pkt[i], pkt[c], gf *) ; + } + } + DEB( /* just test that it works... */ + for ( i = 0 ; i < k ; i++ ) { + if (index[i] < k && index[i] != i) { + fprintf(stderr, "shuffle: after\n"); + for (i=0; i<k ; i++) fprintf(stderr, "%3d ", index[i]); + fprintf(stderr, "\n"); + return 1 ; + } + } + ) + return 0 ; +} + +/* + * build_decode_matrix constructs the encoding matrix given the + * indexes. The matrix must be already allocated as + * a vector of k*k elements, in row-major order + */ +static gf * +build_decode_matrix(struct fec_parms *code, gf *pkt[], int index[]) +{ + int i , k = code->k ; + gf *p, *matrix = NEW_GF_MATRIX(k, k); + + TICK(ticks[9]); + for (i = 0, p = matrix ; i < k ; i++, p += k ) { +#if 1 /* this is simply an optimization, not very useful indeed */ + if (index[i] < k) { + memset(p, '\0', k*sizeof(gf) ); + p[i] = 1 ; + } else +#endif + if (index[i] < code->n ) + memcpy(p, &(code->enc_matrix[index[i]*k]), k*sizeof(gf) ); + else { + fprintf(stderr, "decode: invalid index %d (max %d)\n", + index[i], code->n - 1 ); + free(matrix) ; + return NULL ; + } + } + TICK(ticks[9]); + if (invert_mat(matrix, k)) { + free(matrix); + matrix = NULL ; + } + TOCK(ticks[9]); + return matrix ; +} + +/* + * fec_decode receives as input a vector of packets, the indexes of + * packets, and produces the correct vector as output. + * + * Input: + * code: pointer to code descriptor + * pkt: pointers to received packets. They are modified + * to store the output packets (in place) + * index: pointer to packet indexes (modified) + * sz: size of each packet + */ +int +fec_decode(struct fec_parms *code, gf *pkt[], int index[], int sz) +{ + gf *m_dec ; + gf **new_pkt ; + int row, col , k = code->k ; + + if (GF_BITS > 8) + sz /= 2 ; + + if (shuffle(pkt, index, k)) /* error if true */ + return 1 ; + m_dec = build_decode_matrix(code, pkt, index); + + if (m_dec == NULL) + return 1 ; /* error */ + /* + * do the actual decoding + */ + new_pkt = my_malloc (k * sizeof (gf * ), "new pkt pointers" ); + for (row = 0 ; row < k ; row++ ) { + if (index[row] >= k) { + new_pkt[row] = my_malloc (sz * sizeof (gf), "new pkt buffer" ); + memset(new_pkt[row], '\0', sz * sizeof(gf) ) ; + for (col = 0 ; col < k ; col++ ) + addmul(new_pkt[row], pkt[col], m_dec[row*k + col], sz) ; + } + } + /* + * move pkts to their final destination + */ + for (row = 0 ; row < k ; row++ ) { + if (index[row] >= k) { + memcpy(pkt[row], new_pkt[row], sz*sizeof(gf)); + free(new_pkt[row]); + } + } + free(new_pkt); + free(m_dec); + + return 0; +} + +/*********** end of FEC code -- beginning of test code ************/ + +#if (TEST || DEBUG) +void +test_gf() +{ + int i ; + /* + * test gf tables. Sufficiently tested... + */ + for (i=0; i<= GF_SIZE; i++) { + if (gf_exp[gf_log[i]] != i) + fprintf(stderr, "bad exp/log i %d log %d exp(log) %d\n", + i, gf_log[i], gf_exp[gf_log[i]]); + + if (i != 0 && gf_mul(i, inverse[i]) != 1) + fprintf(stderr, "bad mul/inv i %d inv %d i*inv(i) %d\n", + i, inverse[i], gf_mul(i, inverse[i]) ); + if (gf_mul(0,i) != 0) + fprintf(stderr, "bad mul table 0,%d\n",i); + if (gf_mul(i,0) != 0) + fprintf(stderr, "bad mul table %d,0\n",i); + } +} +#endif /* TEST */ diff --git a/lib/libmtd.c b/lib/libmtd.c new file mode 100644 index 0000000..3ff031c --- /dev/null +++ b/lib/libmtd.c @@ -0,0 +1,1157 @@ +/* + * Copyright (c) International Business Machines Corp., 2006 + * Copyright (C) 2009 Nokia Corporation + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * 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., 675 Mass Ave, Cambridge, MA 02139, USA. + * + * Author: Artem Bityutskiy + * + * MTD library. + */ + +#include <limits.h> +#include <stdlib.h> +#include <stdio.h> +#include <errno.h> +#include <unistd.h> +#include <fcntl.h> +#include <dirent.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <sys/ioctl.h> +#include <mtd/mtd-user.h> + +#include <libmtd.h> +#include "libmtd_int.h" +#include "common.h" + +/** + * mkpath - compose full path from 2 given components. + * @path: the first component + * @name: the second component + * + * This function returns the resulting path in case of success and %NULL in + * case of failure. + */ +static char *mkpath(const char *path, const char *name) +{ + char *n; + int len1 = strlen(path); + int len2 = strlen(name); + + n = malloc(len1 + len2 + 2); + if (!n) { + sys_errmsg("cannot allocate %d bytes", len1 + len2 + 2); + return NULL; + } + + memcpy(n, path, len1); + if (n[len1 - 1] != '/') + n[len1++] = '/'; + + memcpy(n + len1, name, len2 + 1); + return n; +} + +/** + * read_data - read data from a file. + * @file: the file to read from + * @buf: the buffer to read to + * @buf_len: buffer length + * + * This function returns number of read bytes in case of success and %-1 in + * case of failure. Note, if the file contains more then @buf_len bytes of + * date, this function fails with %EINVAL error code. + */ +static int read_data(const char *file, void *buf, int buf_len) +{ + int fd, rd, tmp, tmp1; + + fd = open(file, O_RDONLY); + if (fd == -1) + return -1; + + rd = read(fd, buf, buf_len); + if (rd == -1) { + sys_errmsg("cannot read \"%s\"", file); + goto out_error; + } + + if (rd == buf_len) { + errmsg("contents of \"%s\" is too long", file); + errno = EINVAL; + goto out_error; + } + + ((char *)buf)[rd] = '\0'; + + /* Make sure all data is read */ + tmp1 = read(fd, &tmp, 1); + if (tmp1 == 1) { + sys_errmsg("cannot read \"%s\"", file); + goto out_error; + } + if (tmp1) { + errmsg("file \"%s\" contains too much data (> %d bytes)", + file, buf_len); + errno = EINVAL; + goto out_error; + } + + if (close(fd)) { + sys_errmsg("close failed on \"%s\"", file); + return -1; + } + + return rd; + +out_error: + close(fd); + return -1; +} + +/** + * read_major - read major and minor numbers from a file. + * @file: name of the file to read from + * @major: major number is returned here + * @minor: minor number is returned here + * + * This function returns % in case of success, and %-1 in case of failure. + */ +static int read_major(const char *file, int *major, int *minor) +{ + int ret; + char buf[50]; + + ret = read_data(file, buf, 50); + if (ret < 0) + return ret; + + ret = sscanf(buf, "%d:%d\n", major, minor); + if (ret != 2) { + errno = EINVAL; + return errmsg("\"%s\" does not have major:minor format", file); + } + + if (*major < 0 || *minor < 0) { + errno = EINVAL; + return errmsg("bad major:minor %d:%d in \"%s\"", + *major, *minor, file); + } + + return 0; +} + +/** + * dev_get_major - get major and minor numbers of an MTD device. + * @lib: libmtd descriptor + * @mtd_num: MTD device number + * @major: major number is returned here + * @minor: minor number is returned here + * + * This function returns zero in case of success and %-1 in case of failure. + */ +static int dev_get_major(struct libmtd *lib, int mtd_num, int *major, int *minor) +{ + char file[strlen(lib->mtd_dev) + 50]; + + sprintf(file, lib->mtd_dev, mtd_num); + return read_major(file, major, minor); +} + +/** + * dev_read_data - read data from an MTD device's sysfs file. + * @patt: file pattern to read from + * @mtd_num: MTD device number + * @buf: buffer to read to + * @buf_len: buffer length + * + * This function returns number of read bytes in case of success and %-1 in + * case of failure. + */ +static int dev_read_data(const char *patt, int mtd_num, void *buf, int buf_len) +{ + char file[strlen(patt) + 100]; + + sprintf(file, patt, mtd_num); + return read_data(file, buf, buf_len); +} + +/** + * read_hex_ll - read a hex 'long long' value from a file. + * @file: the file to read from + * @value: the result is stored here + * + * This function reads file @file and interprets its contents as hexadecimal + * 'long long' integer. If this is not true, it fails with %EINVAL error code. + * Returns %0 in case of success and %-1 in case of failure. + */ +static int read_hex_ll(const char *file, long long *value) +{ + int fd, rd; + char buf[50]; + + fd = open(file, O_RDONLY); + if (fd == -1) + return -1; + + rd = read(fd, buf, sizeof(buf)); + if (rd == -1) { + sys_errmsg("cannot read \"%s\"", file); + goto out_error; + } + if (rd == sizeof(buf)) { + errmsg("contents of \"%s\" is too long", file); + errno = EINVAL; + goto out_error; + } + buf[rd] = '\0'; + + if (sscanf(buf, "%llx\n", value) != 1) { + errmsg("cannot read integer from \"%s\"\n", file); + errno = EINVAL; + goto out_error; + } + + if (*value < 0) { + errmsg("negative value %lld in \"%s\"", *value, file); + errno = EINVAL; + goto out_error; + } + + if (close(fd)) + return sys_errmsg("close failed on \"%s\"", file); + + return 0; + +out_error: + close(fd); + return -1; +} + +/** + * read_pos_ll - read a positive 'long long' value from a file. + * @file: the file to read from + * @value: the result is stored here + * + * This function reads file @file and interprets its contents as a positive + * 'long long' integer. If this is not true, it fails with %EINVAL error code. + * Returns %0 in case of success and %-1 in case of failure. + */ +static int read_pos_ll(const char *file, long long *value) +{ + int fd, rd; + char buf[50]; + + fd = open(file, O_RDONLY); + if (fd == -1) + return -1; + + rd = read(fd, buf, 50); + if (rd == -1) { + sys_errmsg("cannot read \"%s\"", file); + goto out_error; + } + if (rd == 50) { + errmsg("contents of \"%s\" is too long", file); + errno = EINVAL; + goto out_error; + } + + if (sscanf(buf, "%lld\n", value) != 1) { + errmsg("cannot read integer from \"%s\"\n", file); + errno = EINVAL; + goto out_error; + } + + if (*value < 0) { + errmsg("negative value %lld in \"%s\"", *value, file); + errno = EINVAL; + goto out_error; + } + + if (close(fd)) + return sys_errmsg("close failed on \"%s\"", file); + + return 0; + +out_error: + close(fd); + return -1; +} + +/** + * read_hex_int - read an 'int' value from a file. + * @file: the file to read from + * @value: the result is stored here + * + * This function is the same as 'read_pos_ll()', but it reads an 'int' + * value, not 'long long'. + */ +static int read_hex_int(const char *file, int *value) +{ + long long res; + + if (read_hex_ll(file, &res)) + return -1; + + /* Make sure the value has correct range */ + if (res > INT_MAX || res < INT_MIN) { + errmsg("value %lld read from file \"%s\" is out of range", + res, file); + errno = EINVAL; + return -1; + } + + *value = res; + return 0; +} + +/** + * read_pos_int - read a positive 'int' value from a file. + * @file: the file to read from + * @value: the result is stored here + * + * This function is the same as 'read_pos_ll()', but it reads an 'int' + * value, not 'long long'. + */ +static int read_pos_int(const char *file, int *value) +{ + long long res; + + if (read_pos_ll(file, &res)) + return -1; + + /* Make sure the value is not too big */ + if (res > INT_MAX) { + errmsg("value %lld read from file \"%s\" is out of range", + res, file); + errno = EINVAL; + return -1; + } + + *value = res; + return 0; +} + +/** + * dev_read_hex_int - read an hex 'int' value from an MTD device sysfs file. + * @patt: file pattern to read from + * @mtd_num: MTD device number + * @value: the result is stored here + * + * This function returns %0 in case of success and %-1 in case of failure. + */ +static int dev_read_hex_int(const char *patt, int mtd_num, int *value) +{ + char file[strlen(patt) + 50]; + + sprintf(file, patt, mtd_num); + return read_hex_int(file, value); +} + +/** + * dev_read_pos_int - read a positive 'int' value from an MTD device sysfs file. + * @patt: file pattern to read from + * @mtd_num: MTD device number + * @value: the result is stored here + * + * This function returns %0 in case of success and %-1 in case of failure. + */ +static int dev_read_pos_int(const char *patt, int mtd_num, int *value) +{ + char file[strlen(patt) + 50]; + + sprintf(file, patt, mtd_num); + return read_pos_int(file, value); +} + +/** + * dev_read_pos_ll - read a positive 'long long' value from an MTD device sysfs file. + * @patt: file pattern to read from + * @mtd_num: MTD device number + * @value: the result is stored here + * + * This function returns %0 in case of success and %-1 in case of failure. + */ +static int dev_read_pos_ll(const char *patt, int mtd_num, long long *value) +{ + char file[strlen(patt) + 50]; + + sprintf(file, patt, mtd_num); + return read_pos_ll(file, value); +} + +/** + * type_str2int - convert MTD device type to integer. + * @str: MTD device type string to convert + * + * This function converts MTD device type string @str, read from sysfs, into an + * integer. + */ +static int type_str2int(const char *str) +{ + if (!strcmp(str, "nand")) + return MTD_NANDFLASH; + if (!strcmp(str, "nor")) + return MTD_NORFLASH; + if (!strcmp(str, "rom")) + return MTD_ROM; + if (!strcmp(str, "absent")) + return MTD_ABSENT; + if (!strcmp(str, "dataflash")) + return MTD_DATAFLASH; + if (!strcmp(str, "ram")) + return MTD_RAM; + if (!strcmp(str, "ubi")) + return MTD_UBIVOLUME; + return -1; +} + +/** + * dev_node2num - find UBI device number by its character device node. + * @lib: MTD library descriptor + * @node: name of the MTD device node + * @mtd_num: MTD device number is returned here + * + * This function returns %0 in case of success and %-1 in case of failure. + */ +static int dev_node2num(struct libmtd *lib, const char *node, int *mtd_num) +{ + struct stat st; + int i, major, minor; + struct mtd_info info; + + if (stat(node, &st)) + return sys_errmsg("cannot get information about \"%s\"", node); + + if (!S_ISCHR(st.st_mode)) { + errmsg("\"%s\" is not a character device", node); + errno = EINVAL; + return -1; + } + + major = major(st.st_rdev); + minor = minor(st.st_rdev); + + if (mtd_get_info((libmtd_t *)lib, &info)) + return -1; + + for (i = info.lowest_mtd_num; i <= info.highest_mtd_num; i++) { + int major1, minor1, ret; + + ret = dev_get_major(lib, i, &major1, &minor1); + if (ret) { + if (errno == ENOENT) + continue; + if (!errno) + break; + return -1; + } + + if (major1 == major && minor1 == minor) { + errno = 0; + *mtd_num = i; + return 0; + } + } + + errno = ENODEV; + return -1; +} + +/** + * sysfs_is_supported - check whether the MTD sub-system supports MTD. + * @lib: MTD library descriptor + * + * The Linux kernel MTD subsystem gained MTD support starting from kernel + * 2.6.30 and libmtd tries to use sysfs interface if possible, because the NAND + * sub-page size is available there (and not available at all in pre-sysfs + * kernels). + * + * Very old kernels did not have "/sys/class/mtd" directory. Not very old + * kernels (e.g., 2.6.29) did have "/sys/class/mtd/mtdX" directories, by there + * were no files there, e.g., the "name" file was not present. So all we can do + * is to check for a "/sys/class/mtd/mtdX/name" file. But this is not a + * reliable check, because if this is a new system with no MTD devices - we'll + * treat it as a pre-sysfs system. + */ +static int sysfs_is_supported(struct libmtd *lib) +{ + int fd, num = -1; + DIR *sysfs_mtd; + char file[strlen(lib->mtd_name) + 10]; + + sysfs_mtd = opendir(lib->sysfs_mtd); + if (!sysfs_mtd) { + if (errno == ENOENT) { + errno = 0; + return 0; + } + return sys_errmsg("cannot open \"%s\"", lib->sysfs_mtd); + } + + /* + * First of all find an "mtdX" directory. This is needed because there + * may be, for example, mtd1 but no mtd0. + */ + while (1) { + int ret, mtd_num; + char tmp_buf[256]; + struct dirent *dirent; + + dirent = readdir(sysfs_mtd); + if (!dirent) + break; + + if (strlen(dirent->d_name) >= 255) { + errmsg("invalid entry in %s: \"%s\"", + lib->sysfs_mtd, dirent->d_name); + errno = EINVAL; + closedir(sysfs_mtd); + return -1; + } + + ret = sscanf(dirent->d_name, MTD_NAME_PATT"%s", + &mtd_num, tmp_buf); + if (ret == 1) { + num = mtd_num; + break; + } + } + + if (closedir(sysfs_mtd)) + return sys_errmsg("closedir failed on \"%s\"", lib->sysfs_mtd); + + if (num == -1) + /* No mtd device, treat this as pre-sysfs system */ + return 0; + + sprintf(file, lib->mtd_name, num); + fd = open(file, O_RDONLY); + if (fd == -1) + return 0; + + if (close(fd)) { + sys_errmsg("close failed on \"%s\"", file); + return -1; + } + + return 1; +} + +libmtd_t libmtd_open(void) +{ + struct libmtd *lib; + + lib = calloc(1, sizeof(struct libmtd)); + if (!lib) + return NULL; + + lib->sysfs_mtd = mkpath("/sys", SYSFS_MTD); + if (!lib->sysfs_mtd) + goto out_error; + + lib->mtd = mkpath(lib->sysfs_mtd, MTD_NAME_PATT); + if (!lib->mtd) + goto out_error; + + lib->mtd_name = mkpath(lib->mtd, MTD_NAME); + if (!lib->mtd_name) + goto out_error; + + if (!sysfs_is_supported(lib)) { + free(lib->mtd); + free(lib->sysfs_mtd); + free(lib->mtd_name); + lib->mtd_name = lib->mtd = lib->sysfs_mtd = NULL; + return lib; + } + + lib->mtd_dev = mkpath(lib->mtd, MTD_DEV); + if (!lib->mtd_dev) + goto out_error; + + lib->mtd_type = mkpath(lib->mtd, MTD_TYPE); + if (!lib->mtd_type) + goto out_error; + + lib->mtd_eb_size = mkpath(lib->mtd, MTD_EB_SIZE); + if (!lib->mtd_eb_size) + goto out_error; + + lib->mtd_size = mkpath(lib->mtd, MTD_SIZE); + if (!lib->mtd_size) + goto out_error; + + lib->mtd_min_io_size = mkpath(lib->mtd, MTD_MIN_IO_SIZE); + if (!lib->mtd_min_io_size) + goto out_error; + + lib->mtd_subpage_size = mkpath(lib->mtd, MTD_SUBPAGE_SIZE); + if (!lib->mtd_subpage_size) + goto out_error; + + lib->mtd_oob_size = mkpath(lib->mtd, MTD_OOB_SIZE); + if (!lib->mtd_oob_size) + goto out_error; + + lib->mtd_region_cnt = mkpath(lib->mtd, MTD_REGION_CNT); + if (!lib->mtd_region_cnt) + goto out_error; + + lib->mtd_flags = mkpath(lib->mtd, MTD_FLAGS); + if (!lib->mtd_flags) + goto out_error; + + lib->sysfs_supported = 1; + return lib; + +out_error: + libmtd_close((libmtd_t)lib); + return NULL; +} + +void libmtd_close(libmtd_t desc) +{ + struct libmtd *lib = (struct libmtd *)desc; + + free(lib->mtd_flags); + free(lib->mtd_region_cnt); + free(lib->mtd_oob_size); + free(lib->mtd_subpage_size); + free(lib->mtd_min_io_size); + free(lib->mtd_size); + free(lib->mtd_eb_size); + free(lib->mtd_type); + free(lib->mtd_dev); + free(lib->mtd_name); + free(lib->mtd); + free(lib->sysfs_mtd); + free(lib); +} + +int mtd_get_info(libmtd_t desc, struct mtd_info *info) +{ + DIR *sysfs_mtd; + struct dirent *dirent; + struct libmtd *lib = (struct libmtd *)desc; + + memset(info, 0, sizeof(struct mtd_info)); + + if (!lib->sysfs_supported) + return legacy_mtd_get_info(info); + + info->sysfs_supported = 1; + + /* + * We have to scan the MTD sysfs directory to identify how many MTD + * devices are present. + */ + sysfs_mtd = opendir(lib->sysfs_mtd); + if (!sysfs_mtd) { + if (errno == ENOENT) { + errno = ENODEV; + return -1; + } + return sys_errmsg("cannot open \"%s\"", lib->sysfs_mtd); + } + + info->lowest_mtd_num = INT_MAX; + while (1) { + int mtd_num, ret; + char tmp_buf[256]; + + errno = 0; + dirent = readdir(sysfs_mtd); + if (!dirent) + break; + + if (strlen(dirent->d_name) >= 255) { + errmsg("invalid entry in %s: \"%s\"", + lib->sysfs_mtd, dirent->d_name); + errno = EINVAL; + goto out_close; + } + + ret = sscanf(dirent->d_name, MTD_NAME_PATT"%s", + &mtd_num, tmp_buf); + if (ret == 1) { + info->mtd_dev_cnt += 1; + if (mtd_num > info->highest_mtd_num) + info->highest_mtd_num = mtd_num; + if (mtd_num < info->lowest_mtd_num) + info->lowest_mtd_num = mtd_num; + } + } + + if (!dirent && errno) { + sys_errmsg("readdir failed on \"%s\"", lib->sysfs_mtd); + goto out_close; + } + + if (closedir(sysfs_mtd)) + return sys_errmsg("closedir failed on \"%s\"", lib->sysfs_mtd); + + if (info->lowest_mtd_num == INT_MAX) + info->lowest_mtd_num = 0; + + return 0; + +out_close: + closedir(sysfs_mtd); + return -1; +} + +int mtd_get_dev_info1(libmtd_t desc, int mtd_num, struct mtd_dev_info *mtd) +{ + int ret; + struct stat st; + struct libmtd *lib = (struct libmtd *)desc; + + memset(mtd, 0, sizeof(struct mtd_dev_info)); + mtd->mtd_num = mtd_num; + + if (!lib->sysfs_supported) + return legacy_get_dev_info1(mtd_num, mtd); + else { + char file[strlen(lib->mtd) + 10]; + + sprintf(file, lib->mtd, mtd_num); + if (stat(file, &st)) { + if (errno == ENOENT) + errno = ENODEV; + return -1; + } + } + + if (dev_get_major(lib, mtd_num, &mtd->major, &mtd->minor)) + return -1; + + ret = dev_read_data(lib->mtd_name, mtd_num, &mtd->name, + MTD_NAME_MAX + 1); + if (ret < 0) + return -1; + ((char *)mtd->name)[ret - 1] = '\0'; + + ret = dev_read_data(lib->mtd_type, mtd_num, &mtd->type_str, + MTD_TYPE_MAX + 1); + if (ret < 0) + return -1; + ((char *)mtd->type_str)[ret - 1] = '\0'; + + if (dev_read_pos_int(lib->mtd_eb_size, mtd_num, &mtd->eb_size)) + return -1; + if (dev_read_pos_ll(lib->mtd_size, mtd_num, &mtd->size)) + return -1; + if (dev_read_pos_int(lib->mtd_min_io_size, mtd_num, &mtd->min_io_size)) + return -1; + if (dev_read_pos_int(lib->mtd_subpage_size, mtd_num, &mtd->subpage_size)) + return -1; + if (dev_read_pos_int(lib->mtd_oob_size, mtd_num, &mtd->oob_size)) + return -1; + if (dev_read_pos_int(lib->mtd_region_cnt, mtd_num, &mtd->region_cnt)) + return -1; + if (dev_read_hex_int(lib->mtd_flags, mtd_num, &ret)) + return -1; + mtd->writable = !!(ret & MTD_WRITEABLE); + + mtd->eb_cnt = mtd->size / mtd->eb_size; + mtd->type = type_str2int(mtd->type_str); + mtd->bb_allowed = !!(mtd->type == MTD_NANDFLASH); + + return 0; +} + +int mtd_get_dev_info(libmtd_t desc, const char *node, struct mtd_dev_info *mtd) +{ + int mtd_num; + struct libmtd *lib = (struct libmtd *)desc; + + if (!lib->sysfs_supported) + return legacy_get_dev_info(node, mtd); + + if (dev_node2num(lib, node, &mtd_num)) + return -1; + + return mtd_get_dev_info1(desc, mtd_num, mtd); +} + +int mtd_erase(const struct mtd_dev_info *mtd, int fd, int eb) +{ + struct erase_info_user ei; + + ei.start = eb * mtd->eb_size;; + ei.length = mtd->eb_size; + return ioctl(fd, MEMERASE, &ei); +} + +/* Patterns to write to a physical eraseblock when torturing it */ +static uint8_t patterns[] = {0xa5, 0x5a, 0x0}; + +/** + * check_pattern - check if buffer contains only a certain byte pattern. + * @buf: buffer to check + * @patt: the pattern to check + * @size: buffer size in bytes + * + * This function returns %1 in there are only @patt bytes in @buf, and %0 if + * something else was also found. + */ +static int check_pattern(const void *buf, uint8_t patt, int size) +{ + int i; + + for (i = 0; i < size; i++) + if (((const uint8_t *)buf)[i] != patt) + return 0; + return 1; +} + +int mtd_torture(const struct mtd_dev_info *mtd, int fd, int eb) +{ + int err, i, patt_count; + void *buf; + + normsg("run torture test for PEB %d", eb); + patt_count = ARRAY_SIZE(patterns); + + buf = malloc(mtd->eb_size); + if (!buf) { + errmsg("cannot allocate %d bytes of memory", mtd->eb_size); + return -1; + } + + for (i = 0; i < patt_count; i++) { + err = mtd_erase(mtd, fd, eb); + if (err) + goto out; + + /* Make sure the PEB contains only 0xFF bytes */ + err = mtd_read(mtd, fd, eb, 0, buf, mtd->eb_size); + if (err) + goto out; + + err = check_pattern(buf, 0xFF, mtd->eb_size); + if (err == 0) { + errmsg("erased PEB %d, but a non-0xFF byte found", eb); + errno = EIO; + goto out; + } + + /* Write a pattern and check it */ + memset(buf, patterns[i], mtd->eb_size); + err = mtd_write(mtd, fd, eb, 0, buf, mtd->eb_size); + if (err) + goto out; + + memset(buf, ~patterns[i], mtd->eb_size); + err = mtd_read(mtd, fd, eb, 0, buf, mtd->eb_size); + if (err) + goto out; + + err = check_pattern(buf, patterns[i], mtd->eb_size); + if (err == 0) { + errmsg("pattern %x checking failed for PEB %d", + patterns[i], eb); + errno = EIO; + goto out; + } + } + + err = 0; + normsg("PEB %d passed torture test, do not mark it a bad", eb); + +out: + free(buf); + return -1; +} + +int mtd_is_bad(const struct mtd_dev_info *mtd, int fd, int eb) +{ + int ret; + loff_t seek; + + if (eb < 0 || eb >= mtd->eb_cnt) { + errmsg("bad eraseblock number %d, mtd%d has %d eraseblocks", + eb, mtd->mtd_num, mtd->eb_cnt); + errno = EINVAL; + return -1; + } + + if (!mtd->bb_allowed) + return 0; + + seek = (loff_t)eb * mtd->eb_size; + ret = ioctl(fd, MEMGETBADBLOCK, &seek); + if (ret == -1) + return sys_errmsg("MEMGETBADBLOCK ioctl failed for " + "eraseblock %d (mtd%d)", eb, mtd->mtd_num); + return ret; +} + +int mtd_mark_bad(const struct mtd_dev_info *mtd, int fd, int eb) +{ + int ret; + loff_t seek; + + if (!mtd->bb_allowed) { + errno = EINVAL; + return -1; + } + + if (eb < 0 || eb >= mtd->eb_cnt) { + errmsg("bad eraseblock number %d, mtd%d has %d eraseblocks", + eb, mtd->mtd_num, mtd->eb_cnt); + errno = EINVAL; + return -1; + } + + seek = (loff_t)eb * mtd->eb_size; + ret = ioctl(fd, MEMSETBADBLOCK, &seek); + if (ret == -1) + return sys_errmsg("MEMSETBADBLOCK ioctl failed for " + "eraseblock %d (mtd%d)", eb, mtd->mtd_num); + return 0; +} + +int mtd_read(const struct mtd_dev_info *mtd, int fd, int eb, int offs, + void *buf, int len) +{ + int ret, rd = 0; + off_t seek; + + if (eb < 0 || eb >= mtd->eb_cnt) { + errmsg("bad eraseblock number %d, mtd%d has %d eraseblocks", + eb, mtd->mtd_num, mtd->eb_cnt); + errno = EINVAL; + return -1; + } + if (offs < 0 || offs + len > mtd->eb_size) { + errmsg("bad offset %d or length %d, mtd%d eraseblock size is %d", + offs, len, mtd->mtd_num, mtd->eb_size); + errno = EINVAL; + return -1; + } + + /* Seek to the beginning of the eraseblock */ + seek = (off_t)eb * mtd->eb_size + offs; + if (lseek(fd, seek, SEEK_SET) != seek) + return sys_errmsg("cannot seek mtd%d to offset %llu", + mtd->mtd_num, (unsigned long long)seek); + + while (rd < len) { + ret = read(fd, buf, len); + if (ret < 0) + return sys_errmsg("cannot read %d bytes from mtd%d (eraseblock %d, offset %d)", + len, mtd->mtd_num, eb, offs); + rd += ret; + } + + return 0; +} + +int mtd_write(const struct mtd_dev_info *mtd, int fd, int eb, int offs, + void *buf, int len) +{ + int ret; + off_t seek; + + if (eb < 0 || eb >= mtd->eb_cnt) { + errmsg("bad eraseblock number %d, mtd%d has %d eraseblocks", + eb, mtd->mtd_num, mtd->eb_cnt); + errno = EINVAL; + return -1; + } + if (offs < 0 || offs + len > mtd->eb_size) { + errmsg("bad offset %d or length %d, mtd%d eraseblock size is %d", + offs, len, mtd->mtd_num, mtd->eb_size); + errno = EINVAL; + return -1; + } + if (offs % mtd->subpage_size) { + errmsg("write offset %d is not aligned to mtd%d min. I/O size %d", + offs, mtd->mtd_num, mtd->subpage_size); + errno = EINVAL; + return -1; + } + if (len % mtd->subpage_size) { + errmsg("write length %d is not aligned to mtd%d min. I/O size %d", + len, mtd->mtd_num, mtd->subpage_size); + errno = EINVAL; + return -1; + } + + /* Seek to the beginning of the eraseblock */ + seek = (off_t)eb * mtd->eb_size + offs; + if (lseek(fd, seek, SEEK_SET) != seek) + return sys_errmsg("cannot seek mtd%d to offset %llu", + mtd->mtd_num, (unsigned long long)seek); + + ret = write(fd, buf, len); + if (ret != len) + return sys_errmsg("cannot write %d bytes to mtd%d (eraseblock %d, offset %d)", + len, mtd->mtd_num, eb, offs); + + return 0; +} + +int mtd_write_img(const struct mtd_dev_info *mtd, int fd, int eb, int offs, + const char *img_name) +{ + int tmp, ret, in_fd, len, written = 0; + off_t seek; + struct stat st; + char *buf; + + if (eb < 0 || eb >= mtd->eb_cnt) { + errmsg("bad eraseblock number %d, mtd%d has %d eraseblocks", + eb, mtd->mtd_num, mtd->eb_cnt); + errno = EINVAL; + return -1; + } + if (offs < 0 || offs >= mtd->eb_size) { + errmsg("bad offset %d, mtd%d eraseblock size is %d", + offs, mtd->mtd_num, mtd->eb_size); + errno = EINVAL; + return -1; + } + if (offs % mtd->subpage_size) { + errmsg("write offset %d is not aligned to mtd%d min. I/O size %d", + offs, mtd->mtd_num, mtd->subpage_size); + errno = EINVAL; + return -1; + } + + in_fd = open(img_name, O_RDONLY); + if (in_fd == -1) + return sys_errmsg("cannot open %s", img_name); + + if (fstat(in_fd, &st)) { + sys_errmsg("cannot stat %s", img_name); + goto out_close; + } + + len = st.st_size; + if (len % mtd->subpage_size) { + errmsg("size of \"%s\" is %d byte, which is not aligned to " + "mtd%d min. I/O size %d", img_name, len, mtd->mtd_num, + mtd->subpage_size); + errno = EINVAL; + goto out_close; + } + tmp = (offs + len + mtd->eb_size - 1) / mtd->eb_size; + if (eb + tmp > mtd->eb_cnt) { + errmsg("\"%s\" image size is %d bytes, mtd%d size is %d " + "eraseblocks, the image does not fit if we write it " + "starting from eraseblock %d, offset %d", + img_name, len, mtd->mtd_num, mtd->eb_cnt, eb, offs); + errno = EINVAL; + goto out_close; + } + + /* Seek to the beginning of the eraseblock */ + seek = (off_t)eb * mtd->eb_size + offs; + if (lseek(fd, seek, SEEK_SET) != seek) { + sys_errmsg("cannot seek mtd%d to offset %llu", + mtd->mtd_num, (unsigned long long)seek); + goto out_close; + } + + buf = malloc(mtd->eb_size); + if (!buf) { + sys_errmsg("cannot allocate %d bytes of memory", mtd->eb_size); + goto out_close; + } + + while (written < len) { + int rd = 0; + + do { + ret = read(in_fd, buf, mtd->eb_size - offs - rd); + if (ret == -1) { + sys_errmsg("cannot read from %s", img_name); + goto out_free; + } + rd += ret; + } while (ret && rd < mtd->eb_size - offs); + + ret = write(fd, buf, rd); + if (ret != rd) { + sys_errmsg("cannot write %d bytes to mtd%d (eraseblock %d, offset %d)", + len, mtd->mtd_num, eb, offs); + goto out_free; + } + + offs = 0; + eb += 1; + written += rd; + } + + free(buf); + close(in_fd); + return 0; + +out_free: + free(buf); +out_close: + close(in_fd); + return -1; +} + +int mtd_probe_node(libmtd_t desc, const char *node) +{ + struct stat st; + struct mtd_info info; + int i, major, minor; + struct libmtd *lib = (struct libmtd *)desc; + + if (stat(node, &st)) + return sys_errmsg("cannot get information about \"%s\"", node); + + if (!S_ISCHR(st.st_mode)) { + errmsg("\"%s\" is not a character device", node); + errno = EINVAL; + return -1; + } + + major = major(st.st_rdev); + minor = minor(st.st_rdev); + + if (mtd_get_info((libmtd_t *)lib, &info)) + return -1; + + if (!lib->sysfs_supported) + return 0; + + for (i = info.lowest_mtd_num; i <= info.highest_mtd_num; i++) { + int major1, minor1, ret; + + ret = dev_get_major(lib, i, &major1, &minor1); + if (ret) { + if (errno == ENOENT) + continue; + if (!errno) + break; + return -1; + } + + if (major1 == major && minor1 == minor) + return 1; + } + + errno = 0; + return -1; +} diff --git a/lib/libmtd_int.h b/lib/libmtd_int.h new file mode 100644 index 0000000..7de4b42 --- /dev/null +++ b/lib/libmtd_int.h @@ -0,0 +1,88 @@ +/* + * Copyright (c) International Business Machines Corp., 2006 + * Copyright (C) 2009 Nokia Corporation + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * 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., 675 Mass Ave, Cambridge, MA 02139, USA. + * + * Author: Artem Bityutskiy + * + * MTD library. + */ + +#ifndef __LIBMTD_INT_H__ +#define __LIBMTD_INT_H__ + +#ifdef __cplusplus +extern "C" { +#endif + +#define PROGRAM_NAME "libmtd" + +#define SYSFS_MTD "class/mtd" +#define MTD_NAME_PATT "mtd%d" +#define MTD_DEV "dev" +#define MTD_NAME "name" +#define MTD_TYPE "type" +#define MTD_EB_SIZE "erasesize" +#define MTD_SIZE "size" +#define MTD_MIN_IO_SIZE "writesize" +#define MTD_SUBPAGE_SIZE "subpagesize" +#define MTD_OOB_SIZE "oobsize" +#define MTD_REGION_CNT "numeraseregions" +#define MTD_FLAGS "flags" + +/** + * libmtd - MTD library description data structure. + * @sysfs_mtd: MTD directory in sysfs + * @mtd: MTD device sysfs directory pattern + * @mtd_dev: MTD device major/minor numbers file pattern + * @mtd_name: MTD device name file pattern + * @mtd_type: MTD device type file pattern + * @mtd_eb_size: MTD device eraseblock size file pattern + * @mtd_size: MTD device size file pattern + * @mtd_min_io_size: minimum I/O unit size file pattern + * @mtd_subpage_size: sub-page size file pattern + * @mtd_oob_size: MTD device OOB size file pattern + * @mtd_region_cnt: count of additional erase regions file pattern + * @mtd_flags: MTD device flags file pattern + * @sysfs_supported: non-zero if sysfs is supported by MTD + */ +struct libmtd +{ + char *sysfs_mtd; + char *mtd; + char *mtd_dev; + char *mtd_name; + char *mtd_type; + char *mtd_eb_size; + char *mtd_size; + char *mtd_min_io_size; + char *mtd_subpage_size; + char *mtd_oob_size; + char *mtd_region_cnt; + char *mtd_flags; + unsigned int sysfs_supported:1; +}; + +int legacy_libmtd_open(void); +int legacy_mtd_get_info(struct mtd_info *info); +int legacy_get_dev_info(const char *node, struct mtd_dev_info *mtd); +int legacy_get_dev_info1(int dev_num, struct mtd_dev_info *mtd); + +#ifdef __cplusplus +} +#endif + +#endif /* !__LIBMTD_INT_H__ */ diff --git a/lib/libmtd_legacy.c b/lib/libmtd_legacy.c new file mode 100644 index 0000000..27fb3f8 --- /dev/null +++ b/lib/libmtd_legacy.c @@ -0,0 +1,359 @@ +/* + * Copyright (C) 2009 Nokia Corporation + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * 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., 675 Mass Ave, Cambridge, MA 02139, USA. + * + * Author: Artem Bityutskiy + * + * This file is part of the MTD library. Implements pre-2.6.30 kernels support, + * where MTD did not have sysfs interface. The main limitation of the old + * kernels was that the sub-page size was not exported to user-space, so it was + * not possible to get sub-page size. + */ + +#include <limits.h> +#include <fcntl.h> +#include <unistd.h> +#include <stdlib.h> +#include <errno.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <sys/ioctl.h> +#include <mtd/mtd-user.h> + +#include <libmtd.h> +#include "libmtd_int.h" +#include "common.h" + +#define MTD_PROC_FILE "/proc/mtd" +#define MTD_DEV_PATT "/dev/mtd%d" +#define MTD_DEV_MAJOR 90 + +#define PROC_MTD_FIRST "dev: size erasesize name\n" +#define PROC_MTD_FIRST_LEN (sizeof(PROC_MTD_FIRST) - 1) +#define PROC_MTD_MAX_LEN 4096 +#define PROC_MTD_PATT "mtd%d: %llx %x" + +/** + * struct proc_parse_info - /proc/mtd parsing information. + * @mtd_num: MTD device number + * @size: device size + * @eb_size: eraseblock size + * @name: device name + * @buf: contents of /proc/mtd + * @data_size: how much data was read into @buf + * @pos: next string in @buf to parse + */ +struct proc_parse_info +{ + int mtd_num; + long long size; + char name[MTD_NAME_MAX + 1]; + int eb_size; + char *buf; + int data_size; + char *next; +}; + +static int proc_parse_start(struct proc_parse_info *pi) +{ + int fd, ret; + + fd = open(MTD_PROC_FILE, O_RDONLY); + if (fd == -1) + return -1; + + pi->buf = malloc(PROC_MTD_MAX_LEN); + if (!pi->buf) { + sys_errmsg("cannot allocate %d bytes of memory", + PROC_MTD_MAX_LEN); + goto out_close; + } + + ret = read(fd, pi->buf, PROC_MTD_MAX_LEN); + if (ret == -1) { + sys_errmsg("cannot read \"%s\"", MTD_PROC_FILE); + goto out_free; + } + + if (ret < PROC_MTD_FIRST_LEN || + memcmp(pi->buf, PROC_MTD_FIRST, PROC_MTD_FIRST_LEN)) { + errmsg("\"%s\" does not start with \"%s\"", MTD_PROC_FILE, + PROC_MTD_FIRST); + goto out_free; + } + + pi->data_size = ret; + pi->next = pi->buf + PROC_MTD_FIRST_LEN; + + close(fd); + return 0; + +out_free: + free(pi->buf); +out_close: + close(fd); + return -1; +} + +static int proc_parse_next(struct proc_parse_info *pi) +{ + int ret, len, pos = pi->next - pi->buf; + char *p, *p1; + + if (pos >= pi->data_size) { + free(pi->buf); + return 0; + } + + ret = sscanf(pi->next, PROC_MTD_PATT, &pi->mtd_num, &pi->size, + &pi->eb_size); + if (ret != 3) + return errmsg("\"%s\" pattern not found", PROC_MTD_PATT); + + p = memchr(pi->next, '\"', pi->data_size - pos); + if (!p) + return errmsg("opening \" not fount"); + p += 1; + pos = p - pi->buf; + if (pos >= pi->data_size) + return errmsg("opening \" not fount"); + + p1 = memchr(p, '\"', pi->data_size - pos); + if (!p1) + return errmsg("closing \" not fount"); + pos = p1 - pi->buf; + if (pos >= pi->data_size) + return errmsg("closing \" not fount"); + + len = p1 - p; + if (len > MTD_NAME_MAX) + return errmsg("too long mtd%d device name", pi->mtd_num); + + memcpy(pi->name, p, len); + pi->name[len] = '\0'; + + if (p1[1] != '\n') + return errmsg("opening \"\n\" not fount"); + pi->next = p1 + 2; + return 1; +} + +/** + * legacy_libmtd_open - legacy version of 'libmtd_open()'. + * + * This function is just checks that MTD is present in the system. Returns + * zero in case of success and %-1 in case of failure. In case of failure, + * errno contains zero if MTD is not present in the system, or contains the + * error code if a real error happened. This is similar to the 'libmtd_open()' + * return conventions. + */ +int legacy_libmtd_open(void) +{ + int fd; + + fd = open(MTD_PROC_FILE, O_RDONLY); + if (fd == -1) { + if (errno == ENOENT) + errno = 0; + return -1; + } + + close(fd); + return 0; +} + +/** + * legacy_mtd_get_info - legacy version of 'mtd_get_info()'. + * @info: the MTD device information is returned here + * + * This function is similar to 'mtd_get_info()' and has the same conventions. + */ +int legacy_mtd_get_info(struct mtd_info *info) +{ + int ret; + struct proc_parse_info pi; + + ret = proc_parse_start(&pi); + if (ret) + return -1; + + info->lowest_mtd_num = INT_MAX; + while (proc_parse_next(&pi)) { + info->mtd_dev_cnt += 1; + if (pi.mtd_num > info->highest_mtd_num) + info->highest_mtd_num = pi.mtd_num; + if (pi.mtd_num < info->lowest_mtd_num) + info->lowest_mtd_num = pi.mtd_num; + } + + return 0; +} + +/** + * legacy_get_dev_info - legacy version of 'mtd_get_dev_info()'. + * @node: name of the MTD device node + * @mtd: the MTD device information is returned here + * + * This function is similar to 'mtd_get_dev_info()' and has the same + * conventions. + */ +int legacy_get_dev_info(const char *node, struct mtd_dev_info *mtd) +{ + struct stat st; + struct mtd_info_user ui; + int fd, ret; + loff_t offs = 0; + struct proc_parse_info pi; + + if (stat(node, &st)) { + sys_errmsg("cannot open \"%s\"", node); + if (errno == ENOENT) + normsg("MTD subsystem is old and does not support " + "sysfs, so MTD character device nodes have " + "to exist"); + } + + if (!S_ISCHR(st.st_mode)) { + errno = EINVAL; + return errmsg("\"%s\" is not a character device", node); + } + + memset(mtd, '\0', sizeof(struct mtd_dev_info)); + mtd->major = major(st.st_rdev); + mtd->minor = minor(st.st_rdev); + + if (mtd->major != MTD_DEV_MAJOR) { + errno = EINVAL; + return errmsg("\"%s\" has major number %d, MTD devices have " + "major %d", node, mtd->major, MTD_DEV_MAJOR); + } + + mtd->mtd_num = mtd->minor / 2; + + fd = open(node, O_RDWR); + if (fd == -1) + return sys_errmsg("cannot open \"%s\"", node); + + if (ioctl(fd, MEMGETINFO, &ui)) { + sys_errmsg("MEMGETINFO ioctl request failed"); + goto out_close; + } + + ret = ioctl(fd, MEMGETBADBLOCK, &offs); + if (ret == -1) { + if (errno != EOPNOTSUPP) { + sys_errmsg("MEMGETBADBLOCK ioctl failed"); + goto out_close; + } + errno = 0; + mtd->bb_allowed = 0; + } else + mtd->bb_allowed = 1; + + mtd->type = ui.type; + mtd->size = ui.size; + mtd->eb_size = ui.erasesize; + mtd->min_io_size = ui.writesize; + + if (mtd->min_io_size <= 0) { + errmsg("mtd%d (%s) has insane min. I/O unit size %d", + mtd->mtd_num, node, mtd->min_io_size); + goto out_close; + } + if (mtd->eb_size <= 0 || mtd->eb_size < mtd->min_io_size) { + errmsg("mtd%d (%s) has insane eraseblock size %d", + mtd->mtd_num, node, mtd->eb_size); + goto out_close; + } + if (mtd->size <= 0 || mtd->size < mtd->eb_size) { + errmsg("mtd%d (%s) has insane size %lld", + mtd->mtd_num, node, mtd->size); + goto out_close; + } + mtd->eb_cnt = mtd->size / mtd->eb_size; + + switch(mtd->type) { + case MTD_ABSENT: + errmsg("mtd%d (%s) is removable and is not present", + mtd->mtd_num, node); + goto out_close; + case MTD_RAM: + strcpy((char *)mtd->type_str, "ram"); + break; + case MTD_ROM: + strcpy((char *)mtd->type_str, "rom"); + break; + case MTD_NORFLASH: + strcpy((char *)mtd->type_str, "nor"); + break; + case MTD_NANDFLASH: + strcpy((char *)mtd->type_str, "nand"); + break; + case MTD_DATAFLASH: + strcpy((char *)mtd->type_str, "dataflash"); + break; + case MTD_UBIVOLUME: + strcpy((char *)mtd->type_str, "ubi"); + break; + default: + goto out_close; + } + + if (ui.flags & MTD_WRITEABLE) + mtd->writable = 1; + mtd->subpage_size = mtd->min_io_size; + + close(fd); + + /* + * Unfortunately, the device name is not available via ioctl, and + * we have to parse /proc/mtd to get it. + */ + ret = proc_parse_start(&pi); + if (ret) + return -1; + + while (proc_parse_next(&pi)) { + if (pi.mtd_num == mtd->mtd_num) { + strcpy((char *)mtd->name, pi.name); + return 0; + } + } + + errmsg("mtd%d not found in \"%s\"", mtd->mtd_num, MTD_PROC_FILE); + errno = ENOENT; + return -1; + +out_close: + close(fd); + return -1; +} + +/** + * legacy_get_dev_info1 - legacy version of 'mtd_get_dev_info1()'. + * @node: name of the MTD device node + * @mtd: the MTD device information is returned here + * + * This function is similar to 'mtd_get_dev_info1()' and has the same + * conventions. + */ +int legacy_get_dev_info1(int mtd_num, struct mtd_dev_info *mtd) +{ + char node[sizeof(MTD_DEV_PATT) + 20]; + + sprintf(node, MTD_DEV_PATT, mtd_num); + return legacy_get_dev_info(node, mtd); +} |