diff options
Diffstat (limited to 'roms/u-boot/fs/fat/fat_write.c')
-rw-r--r-- | roms/u-boot/fs/fat/fat_write.c | 1773 |
1 files changed, 1773 insertions, 0 deletions
diff --git a/roms/u-boot/fs/fat/fat_write.c b/roms/u-boot/fs/fat/fat_write.c new file mode 100644 index 000000000..8ff2f6def --- /dev/null +++ b/roms/u-boot/fs/fat/fat_write.c @@ -0,0 +1,1773 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * fat_write.c + * + * R/W (V)FAT 12/16/32 filesystem implementation by Donggeun Kim + */ + +#include <common.h> +#include <command.h> +#include <config.h> +#include <div64.h> +#include <fat.h> +#include <log.h> +#include <malloc.h> +#include <part.h> +#include <rand.h> +#include <asm/byteorder.h> +#include <asm/cache.h> +#include <linux/ctype.h> +#include <linux/math64.h> +#include "fat.c" + +static dir_entry *find_directory_entry(fat_itr *itr, char *filename); +static int new_dir_table(fat_itr *itr); + +/* Characters that may only be used in long file names */ +static const char LONG_ONLY_CHARS[] = "+,;=[]"; + +/* Combined size of the name and ext fields in the directory entry */ +#define SHORT_NAME_SIZE 11 + +/** + * str2fat() - convert string to valid FAT name characters + * + * Stop when reaching end of @src or a period. + * Ignore spaces. + * Replace characters that may only be used in long names by underscores. + * Convert lower case characters to upper case. + * + * To avoid assumptions about the code page we do not use characters + * above 0x7f for the short name. + * + * @dest: destination buffer + * @src: source buffer + * @length: size of destination buffer + * Return: number of bytes in destination buffer + */ +static int str2fat(char *dest, char *src, int length) +{ + int i; + + for (i = 0; i < length; ++src) { + char c = *src; + + if (!c || c == '.') + break; + if (c == ' ') + continue; + if (strchr(LONG_ONLY_CHARS, c) || c > 0x7f) + c = '_'; + else if (c >= 'a' && c <= 'z') + c &= 0xdf; + dest[i] = c; + ++i; + } + return i; +} + +/** + * fat_move_to_cluster() - position to first directory entry in cluster + * + * @itr: directory iterator + * @cluster cluster + * Return: 0 for success, -EIO on error + */ +static int fat_move_to_cluster(fat_itr *itr, unsigned int cluster) +{ + unsigned int nbytes; + + /* position to the start of the directory */ + itr->next_clust = cluster; + itr->last_cluster = 0; + if (!fat_next_cluster(itr, &nbytes)) + return -EIO; + itr->dent = (dir_entry *)itr->block; + itr->remaining = nbytes / sizeof(dir_entry) - 1; + return 0; +} + +/** + * set_name() - set short name in directory entry + * + * The function determines if the @filename is a valid short name. + * In this case no long name is needed. + * + * If a long name is needed, a short name is constructed. + * + * @itr: directory iterator + * @filename: long file name + * @shortname: buffer of 11 bytes to receive chosen short name and extension + * Return: number of directory entries needed, negative on error + */ +static int set_name(fat_itr *itr, const char *filename, char *shortname) +{ + char *period; + char *pos; + int period_location; + char buf[13]; + int i; + int ret; + struct nameext dirent; + + if (!filename) + return -EIO; + + /* Initialize buffer */ + memset(&dirent, ' ', sizeof(dirent)); + + /* Convert filename to upper case short name */ + period = strrchr(filename, '.'); + pos = (char *)filename; + if (*pos == '.') { + pos = period + 1; + period = 0; + } + if (period) + str2fat(dirent.ext, period + 1, sizeof(dirent.ext)); + period_location = str2fat(dirent.name, pos, sizeof(dirent.name)); + if (period_location < 0) + return period_location; + if (*dirent.name == ' ') + *dirent.name = '_'; + /* 0xe5 signals a deleted directory entry. Replace it by 0x05. */ + if (*dirent.name == 0xe5) + *dirent.name = 0x05; + + /* If filename and short name are the same, quit. */ + sprintf(buf, "%.*s.%.3s", period_location, dirent.name, dirent.ext); + if (!strcmp(buf, filename)) { + ret = 1; + goto out; + } + + /* Construct an indexed short name */ + for (i = 1; i < 0x200000; ++i) { + int suffix_len; + int suffix_start; + int j; + + /* To speed up the search use random numbers */ + if (i < 10) { + j = i; + } else { + j = 30 - fls(i); + j = 10 + (rand() >> j); + } + sprintf(buf, "~%d", j); + suffix_len = strlen(buf); + suffix_start = 8 - suffix_len; + if (suffix_start > period_location) + suffix_start = period_location; + memcpy(dirent.name + suffix_start, buf, suffix_len); + if (*dirent.ext != ' ') + sprintf(buf, "%.*s.%.3s", suffix_start + suffix_len, + dirent.name, dirent.ext); + else + sprintf(buf, "%.*s", suffix_start + suffix_len, + dirent.name); + debug("generated short name: %s\n", buf); + + /* Check that the short name does not exist yet. */ + ret = fat_move_to_cluster(itr, itr->start_clust); + if (ret) + return ret; + if (find_directory_entry(itr, buf)) + continue; + + debug("chosen short name: %s\n", buf); + /* Each long name directory entry takes 13 characters. */ + ret = (strlen(filename) + 25) / 13; + goto out; + } + return -EIO; +out: + memcpy(shortname, &dirent, SHORT_NAME_SIZE); + return ret; +} + +static int total_sector; +static int disk_write(__u32 block, __u32 nr_blocks, void *buf) +{ + ulong ret; + + if (!cur_dev) + return -1; + + if (cur_part_info.start + block + nr_blocks > + cur_part_info.start + total_sector) { + printf("error: overflow occurs\n"); + return -1; + } + + ret = blk_dwrite(cur_dev, cur_part_info.start + block, nr_blocks, buf); + if (nr_blocks && ret == 0) + return -1; + + return ret; +} + +/* + * Write fat buffer into block device + */ +static int flush_dirty_fat_buffer(fsdata *mydata) +{ + int getsize = FATBUFBLOCKS; + __u32 fatlength = mydata->fatlength; + __u8 *bufptr = mydata->fatbuf; + __u32 startblock = mydata->fatbufnum * FATBUFBLOCKS; + + debug("debug: evicting %d, dirty: %d\n", mydata->fatbufnum, + (int)mydata->fat_dirty); + + if ((!mydata->fat_dirty) || (mydata->fatbufnum == -1)) + return 0; + + /* Cap length if fatlength is not a multiple of FATBUFBLOCKS */ + if (startblock + getsize > fatlength) + getsize = fatlength - startblock; + + startblock += mydata->fat_sect; + + /* Write FAT buf */ + if (disk_write(startblock, getsize, bufptr) < 0) { + debug("error: writing FAT blocks\n"); + return -1; + } + + if (mydata->fats == 2) { + /* Update corresponding second FAT blocks */ + startblock += mydata->fatlength; + if (disk_write(startblock, getsize, bufptr) < 0) { + debug("error: writing second FAT blocks\n"); + return -1; + } + } + mydata->fat_dirty = 0; + + return 0; +} + +/** + * fat_find_empty_dentries() - find a sequence of available directory entries + * + * @itr: directory iterator + * @count: number of directory entries to find + * Return: 0 on success or negative error number + */ +static int fat_find_empty_dentries(fat_itr *itr, int count) +{ + unsigned int cluster; + dir_entry *dent; + int remaining; + unsigned int n = 0; + int ret; + + ret = fat_move_to_cluster(itr, itr->start_clust); + if (ret) + return ret; + + for (;;) { + if (!itr->dent) { + log_debug("Not enough directory entries available\n"); + return -ENOSPC; + } + switch (itr->dent->nameext.name[0]) { + case 0x00: + case DELETED_FLAG: + if (!n) { + /* Remember first deleted directory entry */ + cluster = itr->clust; + dent = itr->dent; + remaining = itr->remaining; + } + ++n; + if (n == count) + goto out; + break; + default: + n = 0; + break; + } + + next_dent(itr); + if (!itr->dent && + (!itr->is_root || itr->fsdata->fatsize == 32) && + new_dir_table(itr)) + return -ENOSPC; + } +out: + /* Position back to first directory entry */ + if (itr->clust != cluster) { + ret = fat_move_to_cluster(itr, cluster); + if (ret) + return ret; + } + itr->dent = dent; + itr->remaining = remaining; + return 0; +} + +/* + * Set the file name information from 'name' into 'slotptr', + */ +static int str2slot(dir_slot *slotptr, const char *name, int *idx) +{ + int j, end_idx = 0; + + for (j = 0; j <= 8; j += 2) { + if (name[*idx] == 0x00) { + slotptr->name0_4[j] = 0; + slotptr->name0_4[j + 1] = 0; + end_idx++; + goto name0_4; + } + slotptr->name0_4[j] = name[*idx]; + (*idx)++; + end_idx++; + } + for (j = 0; j <= 10; j += 2) { + if (name[*idx] == 0x00) { + slotptr->name5_10[j] = 0; + slotptr->name5_10[j + 1] = 0; + end_idx++; + goto name5_10; + } + slotptr->name5_10[j] = name[*idx]; + (*idx)++; + end_idx++; + } + for (j = 0; j <= 2; j += 2) { + if (name[*idx] == 0x00) { + slotptr->name11_12[j] = 0; + slotptr->name11_12[j + 1] = 0; + end_idx++; + goto name11_12; + } + slotptr->name11_12[j] = name[*idx]; + (*idx)++; + end_idx++; + } + + if (name[*idx] == 0x00) + return 1; + + return 0; +/* Not used characters are filled with 0xff 0xff */ +name0_4: + for (; end_idx < 5; end_idx++) { + slotptr->name0_4[end_idx * 2] = 0xff; + slotptr->name0_4[end_idx * 2 + 1] = 0xff; + } + end_idx = 5; +name5_10: + end_idx -= 5; + for (; end_idx < 6; end_idx++) { + slotptr->name5_10[end_idx * 2] = 0xff; + slotptr->name5_10[end_idx * 2 + 1] = 0xff; + } + end_idx = 11; +name11_12: + end_idx -= 11; + for (; end_idx < 2; end_idx++) { + slotptr->name11_12[end_idx * 2] = 0xff; + slotptr->name11_12[end_idx * 2 + 1] = 0xff; + } + + return 1; +} + +static int flush_dir(fat_itr *itr); + +/** + * fill_dir_slot() - fill directory entries for long name + * + * @itr: directory iterator + * @l_name: long name + * @shortname: short name + * Return: 0 for success, -errno otherwise + */ +static int +fill_dir_slot(fat_itr *itr, const char *l_name, const char *shortname) +{ + __u8 temp_dir_slot_buffer[MAX_LFN_SLOT * sizeof(dir_slot)]; + dir_slot *slotptr = (dir_slot *)temp_dir_slot_buffer; + __u8 counter = 0, checksum; + int idx = 0, ret; + + /* Get short file name checksum value */ + checksum = mkcksum((void *)shortname); + + do { + memset(slotptr, 0x00, sizeof(dir_slot)); + ret = str2slot(slotptr, l_name, &idx); + slotptr->id = ++counter; + slotptr->attr = ATTR_VFAT; + slotptr->alias_checksum = checksum; + slotptr++; + } while (ret == 0); + + slotptr--; + slotptr->id |= LAST_LONG_ENTRY_MASK; + + while (counter >= 1) { + memcpy(itr->dent, slotptr, sizeof(dir_slot)); + slotptr--; + counter--; + + if (!itr->remaining) { + /* Write directory table to device */ + ret = flush_dir(itr); + if (ret) + return ret; + } + + next_dent(itr); + if (!itr->dent) + return -EIO; + } + + return 0; +} + +/* + * Set the entry at index 'entry' in a FAT (12/16/32) table. + */ +static int set_fatent_value(fsdata *mydata, __u32 entry, __u32 entry_value) +{ + __u32 bufnum, offset, off16; + __u16 val1, val2; + + switch (mydata->fatsize) { + case 32: + bufnum = entry / FAT32BUFSIZE; + offset = entry - bufnum * FAT32BUFSIZE; + break; + case 16: + bufnum = entry / FAT16BUFSIZE; + offset = entry - bufnum * FAT16BUFSIZE; + break; + case 12: + bufnum = entry / FAT12BUFSIZE; + offset = entry - bufnum * FAT12BUFSIZE; + break; + default: + /* Unsupported FAT size */ + return -1; + } + + /* Read a new block of FAT entries into the cache. */ + if (bufnum != mydata->fatbufnum) { + int getsize = FATBUFBLOCKS; + __u8 *bufptr = mydata->fatbuf; + __u32 fatlength = mydata->fatlength; + __u32 startblock = bufnum * FATBUFBLOCKS; + + /* Cap length if fatlength is not a multiple of FATBUFBLOCKS */ + if (startblock + getsize > fatlength) + getsize = fatlength - startblock; + + if (flush_dirty_fat_buffer(mydata) < 0) + return -1; + + startblock += mydata->fat_sect; + + if (disk_read(startblock, getsize, bufptr) < 0) { + debug("Error reading FAT blocks\n"); + return -1; + } + mydata->fatbufnum = bufnum; + } + + /* Mark as dirty */ + mydata->fat_dirty = 1; + + /* Set the actual entry */ + switch (mydata->fatsize) { + case 32: + ((__u32 *) mydata->fatbuf)[offset] = cpu_to_le32(entry_value); + break; + case 16: + ((__u16 *) mydata->fatbuf)[offset] = cpu_to_le16(entry_value); + break; + case 12: + off16 = (offset * 3) / 4; + + switch (offset & 0x3) { + case 0: + val1 = cpu_to_le16(entry_value) & 0xfff; + ((__u16 *)mydata->fatbuf)[off16] &= ~0xfff; + ((__u16 *)mydata->fatbuf)[off16] |= val1; + break; + case 1: + val1 = cpu_to_le16(entry_value) & 0xf; + val2 = (cpu_to_le16(entry_value) >> 4) & 0xff; + + ((__u16 *)mydata->fatbuf)[off16] &= ~0xf000; + ((__u16 *)mydata->fatbuf)[off16] |= (val1 << 12); + + ((__u16 *)mydata->fatbuf)[off16 + 1] &= ~0xff; + ((__u16 *)mydata->fatbuf)[off16 + 1] |= val2; + break; + case 2: + val1 = cpu_to_le16(entry_value) & 0xff; + val2 = (cpu_to_le16(entry_value) >> 8) & 0xf; + + ((__u16 *)mydata->fatbuf)[off16] &= ~0xff00; + ((__u16 *)mydata->fatbuf)[off16] |= (val1 << 8); + + ((__u16 *)mydata->fatbuf)[off16 + 1] &= ~0xf; + ((__u16 *)mydata->fatbuf)[off16 + 1] |= val2; + break; + case 3: + val1 = cpu_to_le16(entry_value) & 0xfff; + ((__u16 *)mydata->fatbuf)[off16] &= ~0xfff0; + ((__u16 *)mydata->fatbuf)[off16] |= (val1 << 4); + break; + default: + break; + } + + break; + default: + return -1; + } + + return 0; +} + +/* + * Determine the next free cluster after 'entry' in a FAT (12/16/32) table + * and link it to 'entry'. EOC marker is not set on returned entry. + */ +static __u32 determine_fatent(fsdata *mydata, __u32 entry) +{ + __u32 next_fat, next_entry = entry + 1; + + while (1) { + next_fat = get_fatent(mydata, next_entry); + if (next_fat == 0) { + /* found free entry, link to entry */ + set_fatent_value(mydata, entry, next_entry); + break; + } + next_entry++; + } + debug("FAT%d: entry: %08x, entry_value: %04x\n", + mydata->fatsize, entry, next_entry); + + return next_entry; +} + +/** + * set_sectors() - write data to sectors + * + * Write 'size' bytes from 'buffer' into the specified sector. + * + * @mydata: data to be written + * @startsect: sector to be written to + * @buffer: data to be written + * @size: bytes to be written (but not more than the size of a cluster) + * Return: 0 on success, -1 otherwise + */ +static int +set_sectors(fsdata *mydata, u32 startsect, u8 *buffer, u32 size) +{ + int ret; + + debug("startsect: %d\n", startsect); + + if ((unsigned long)buffer & (ARCH_DMA_MINALIGN - 1)) { + ALLOC_CACHE_ALIGN_BUFFER(__u8, tmpbuf, mydata->sect_size); + + debug("FAT: Misaligned buffer address (%p)\n", buffer); + + while (size >= mydata->sect_size) { + memcpy(tmpbuf, buffer, mydata->sect_size); + ret = disk_write(startsect++, 1, tmpbuf); + if (ret != 1) { + debug("Error writing data (got %d)\n", ret); + return -1; + } + + buffer += mydata->sect_size; + size -= mydata->sect_size; + } + } else if (size >= mydata->sect_size) { + u32 nsects; + + nsects = size / mydata->sect_size; + ret = disk_write(startsect, nsects, buffer); + if (ret != nsects) { + debug("Error writing data (got %d)\n", ret); + return -1; + } + + startsect += nsects; + buffer += nsects * mydata->sect_size; + size -= nsects * mydata->sect_size; + } + + if (size) { + ALLOC_CACHE_ALIGN_BUFFER(__u8, tmpbuf, mydata->sect_size); + /* Do not leak content of stack */ + memset(tmpbuf, 0, mydata->sect_size); + memcpy(tmpbuf, buffer, size); + ret = disk_write(startsect, 1, tmpbuf); + if (ret != 1) { + debug("Error writing data (got %d)\n", ret); + return -1; + } + } + + return 0; +} + +/** + * set_cluster() - write data to cluster + * + * Write 'size' bytes from 'buffer' into the specified cluster. + * + * @mydata: data to be written + * @clustnum: cluster to be written to + * @buffer: data to be written + * @size: bytes to be written (but not more than the size of a cluster) + * Return: 0 on success, -1 otherwise + */ +static int +set_cluster(fsdata *mydata, u32 clustnum, u8 *buffer, u32 size) +{ + return set_sectors(mydata, clust_to_sect(mydata, clustnum), + buffer, size); +} + +/** + * flush_dir() - flush directory + * + * @itr: directory iterator + * Return: 0 for success, -EIO on error + */ +static int flush_dir(fat_itr *itr) +{ + fsdata *mydata = itr->fsdata; + u32 startsect, sect_offset, nsects; + int ret; + + if (!itr->is_root || mydata->fatsize == 32) { + ret = set_cluster(mydata, itr->clust, itr->block, + mydata->clust_size * mydata->sect_size); + goto out; + } + + sect_offset = itr->clust * mydata->clust_size; + startsect = mydata->rootdir_sect + sect_offset; + /* do not write past the end of rootdir */ + nsects = min_t(u32, mydata->clust_size, + mydata->rootdir_size - sect_offset); + + ret = set_sectors(mydata, startsect, itr->block, + nsects * mydata->sect_size); +out: + if (ret) { + log_err("Error: writing directory entry\n"); + return -EIO; + } + return 0; +} + +/* + * Read and modify data on existing and consecutive cluster blocks + */ +static int +get_set_cluster(fsdata *mydata, __u32 clustnum, loff_t pos, __u8 *buffer, + loff_t size, loff_t *gotsize) +{ + static u8 *tmpbuf_cluster; + unsigned int bytesperclust = mydata->clust_size * mydata->sect_size; + __u32 startsect; + loff_t wsize; + int clustcount, i, ret; + + *gotsize = 0; + if (!size) + return 0; + + if (!tmpbuf_cluster) { + tmpbuf_cluster = memalign(ARCH_DMA_MINALIGN, MAX_CLUSTSIZE); + if (!tmpbuf_cluster) + return -1; + } + + assert(pos < bytesperclust); + startsect = clust_to_sect(mydata, clustnum); + + debug("clustnum: %d, startsect: %d, pos: %lld\n", + clustnum, startsect, pos); + + /* partial write at beginning */ + if (pos) { + wsize = min(bytesperclust - pos, size); + ret = disk_read(startsect, mydata->clust_size, tmpbuf_cluster); + if (ret != mydata->clust_size) { + debug("Error reading data (got %d)\n", ret); + return -1; + } + + memcpy(tmpbuf_cluster + pos, buffer, wsize); + ret = disk_write(startsect, mydata->clust_size, tmpbuf_cluster); + if (ret != mydata->clust_size) { + debug("Error writing data (got %d)\n", ret); + return -1; + } + + size -= wsize; + buffer += wsize; + *gotsize += wsize; + + startsect += mydata->clust_size; + + if (!size) + return 0; + } + + /* full-cluster write */ + if (size >= bytesperclust) { + clustcount = lldiv(size, bytesperclust); + + if (!((unsigned long)buffer & (ARCH_DMA_MINALIGN - 1))) { + wsize = clustcount * bytesperclust; + ret = disk_write(startsect, + clustcount * mydata->clust_size, + buffer); + if (ret != clustcount * mydata->clust_size) { + debug("Error writing data (got %d)\n", ret); + return -1; + } + + size -= wsize; + buffer += wsize; + *gotsize += wsize; + + startsect += clustcount * mydata->clust_size; + } else { + for (i = 0; i < clustcount; i++) { + memcpy(tmpbuf_cluster, buffer, bytesperclust); + ret = disk_write(startsect, + mydata->clust_size, + tmpbuf_cluster); + if (ret != mydata->clust_size) { + debug("Error writing data (got %d)\n", + ret); + return -1; + } + + size -= bytesperclust; + buffer += bytesperclust; + *gotsize += bytesperclust; + + startsect += mydata->clust_size; + } + } + } + + /* partial write at end */ + if (size) { + wsize = size; + ret = disk_read(startsect, mydata->clust_size, tmpbuf_cluster); + if (ret != mydata->clust_size) { + debug("Error reading data (got %d)\n", ret); + return -1; + } + memcpy(tmpbuf_cluster, buffer, wsize); + ret = disk_write(startsect, mydata->clust_size, tmpbuf_cluster); + if (ret != mydata->clust_size) { + debug("Error writing data (got %d)\n", ret); + return -1; + } + + size -= wsize; + *gotsize += wsize; + } + + assert(!size); + + return 0; +} + +/* + * Find the first empty cluster + */ +static int find_empty_cluster(fsdata *mydata) +{ + __u32 fat_val, entry = 3; + + while (1) { + fat_val = get_fatent(mydata, entry); + if (fat_val == 0) + break; + entry++; + } + + return entry; +} + +/** + * new_dir_table() - allocate a cluster for additional directory entries + * + * @itr: directory iterator + * Return: 0 on success, -EIO otherwise + */ +static int new_dir_table(fat_itr *itr) +{ + fsdata *mydata = itr->fsdata; + int dir_newclust = 0; + int dir_oldclust = itr->clust; + unsigned int bytesperclust = mydata->clust_size * mydata->sect_size; + + dir_newclust = find_empty_cluster(mydata); + + /* + * Flush before updating FAT to ensure valid directory structure + * in case of failure. + */ + itr->clust = dir_newclust; + itr->next_clust = dir_newclust; + memset(itr->block, 0x00, bytesperclust); + if (flush_dir(itr)) + return -EIO; + + set_fatent_value(mydata, dir_oldclust, dir_newclust); + if (mydata->fatsize == 32) + set_fatent_value(mydata, dir_newclust, 0xffffff8); + else if (mydata->fatsize == 16) + set_fatent_value(mydata, dir_newclust, 0xfff8); + else if (mydata->fatsize == 12) + set_fatent_value(mydata, dir_newclust, 0xff8); + + if (flush_dirty_fat_buffer(mydata) < 0) + return -EIO; + + itr->dent = (dir_entry *)itr->block; + itr->last_cluster = 1; + itr->remaining = bytesperclust / sizeof(dir_entry) - 1; + + return 0; +} + +/* + * Set empty cluster from 'entry' to the end of a file + */ +static int clear_fatent(fsdata *mydata, __u32 entry) +{ + __u32 fat_val; + + while (!CHECK_CLUST(entry, mydata->fatsize)) { + fat_val = get_fatent(mydata, entry); + if (fat_val != 0) + set_fatent_value(mydata, entry, 0); + else + break; + + entry = fat_val; + } + + /* Flush fat buffer */ + if (flush_dirty_fat_buffer(mydata) < 0) + return -1; + + return 0; +} + +/* + * Set start cluster in directory entry + */ +static void set_start_cluster(const fsdata *mydata, dir_entry *dentptr, + __u32 start_cluster) +{ + if (mydata->fatsize == 32) + dentptr->starthi = + cpu_to_le16((start_cluster & 0xffff0000) >> 16); + dentptr->start = cpu_to_le16(start_cluster & 0xffff); +} + +/* + * Check whether adding a file makes the file system to + * exceed the size of the block device + * Return -1 when overflow occurs, otherwise return 0 + */ +static int check_overflow(fsdata *mydata, __u32 clustnum, loff_t size) +{ + __u32 startsect, sect_num, offset; + + if (clustnum > 0) + startsect = clust_to_sect(mydata, clustnum); + else + startsect = mydata->rootdir_sect; + + sect_num = div_u64_rem(size, mydata->sect_size, &offset); + + if (offset != 0) + sect_num++; + + if (startsect + sect_num > total_sector) + return -1; + return 0; +} + +/* + * Write at most 'maxsize' bytes from 'buffer' into + * the file associated with 'dentptr' + * Update the number of bytes written in *gotsize and return 0 + * or return -1 on fatal errors. + */ +static int +set_contents(fsdata *mydata, dir_entry *dentptr, loff_t pos, __u8 *buffer, + loff_t maxsize, loff_t *gotsize) +{ + unsigned int bytesperclust = mydata->clust_size * mydata->sect_size; + __u32 curclust = START(dentptr); + __u32 endclust = 0, newclust = 0; + u64 cur_pos, filesize; + loff_t offset, actsize, wsize; + + *gotsize = 0; + filesize = pos + maxsize; + + debug("%llu bytes\n", filesize); + + if (!filesize) { + if (!curclust) + return 0; + if (!CHECK_CLUST(curclust, mydata->fatsize) || + IS_LAST_CLUST(curclust, mydata->fatsize)) { + clear_fatent(mydata, curclust); + set_start_cluster(mydata, dentptr, 0); + return 0; + } + debug("curclust: 0x%x\n", curclust); + debug("Invalid FAT entry\n"); + return -1; + } + + if (!curclust) { + assert(pos == 0); + goto set_clusters; + } + + /* go to cluster at pos */ + cur_pos = bytesperclust; + while (1) { + if (pos <= cur_pos) + break; + if (IS_LAST_CLUST(curclust, mydata->fatsize)) + break; + + newclust = get_fatent(mydata, curclust); + if (!IS_LAST_CLUST(newclust, mydata->fatsize) && + CHECK_CLUST(newclust, mydata->fatsize)) { + debug("curclust: 0x%x\n", curclust); + debug("Invalid FAT entry\n"); + return -1; + } + + cur_pos += bytesperclust; + curclust = newclust; + } + if (IS_LAST_CLUST(curclust, mydata->fatsize)) { + assert(pos == cur_pos); + goto set_clusters; + } + + assert(pos < cur_pos); + cur_pos -= bytesperclust; + + /* overwrite */ + assert(IS_LAST_CLUST(curclust, mydata->fatsize) || + !CHECK_CLUST(curclust, mydata->fatsize)); + + while (1) { + /* search for allocated consecutive clusters */ + actsize = bytesperclust; + endclust = curclust; + while (1) { + if (filesize <= (cur_pos + actsize)) + break; + + newclust = get_fatent(mydata, endclust); + + if (newclust != endclust + 1) + break; + if (IS_LAST_CLUST(newclust, mydata->fatsize)) + break; + if (CHECK_CLUST(newclust, mydata->fatsize)) { + debug("curclust: 0x%x\n", curclust); + debug("Invalid FAT entry\n"); + return -1; + } + + actsize += bytesperclust; + endclust = newclust; + } + + /* overwrite to <curclust..endclust> */ + if (pos < cur_pos) + offset = 0; + else + offset = pos - cur_pos; + wsize = min_t(unsigned long long, actsize, filesize - cur_pos); + wsize -= offset; + + if (get_set_cluster(mydata, curclust, offset, + buffer, wsize, &actsize)) { + printf("Error get-and-setting cluster\n"); + return -1; + } + buffer += wsize; + *gotsize += wsize; + cur_pos += offset + wsize; + + if (filesize <= cur_pos) + break; + + if (IS_LAST_CLUST(newclust, mydata->fatsize)) + /* no more clusters */ + break; + + curclust = newclust; + } + + if (filesize <= cur_pos) { + /* no more write */ + newclust = get_fatent(mydata, endclust); + if (!IS_LAST_CLUST(newclust, mydata->fatsize)) { + /* truncate the rest */ + clear_fatent(mydata, newclust); + + /* Mark end of file in FAT */ + if (mydata->fatsize == 12) + newclust = 0xfff; + else if (mydata->fatsize == 16) + newclust = 0xffff; + else if (mydata->fatsize == 32) + newclust = 0xfffffff; + set_fatent_value(mydata, endclust, newclust); + } + + return 0; + } + + curclust = endclust; + filesize -= cur_pos; + assert(!do_div(cur_pos, bytesperclust)); + +set_clusters: + /* allocate and write */ + assert(!pos); + + /* Assure that curclust is valid */ + if (!curclust) { + curclust = find_empty_cluster(mydata); + set_start_cluster(mydata, dentptr, curclust); + } else { + newclust = get_fatent(mydata, curclust); + + if (IS_LAST_CLUST(newclust, mydata->fatsize)) { + newclust = determine_fatent(mydata, curclust); + set_fatent_value(mydata, curclust, newclust); + curclust = newclust; + } else { + debug("error: something wrong\n"); + return -1; + } + } + + /* TODO: already partially written */ + if (check_overflow(mydata, curclust, filesize)) { + printf("Error: no space left: %llu\n", filesize); + return -1; + } + + actsize = bytesperclust; + endclust = curclust; + do { + /* search for consecutive clusters */ + while (actsize < filesize) { + newclust = determine_fatent(mydata, endclust); + + if ((newclust - 1) != endclust) + /* write to <curclust..endclust> */ + goto getit; + + if (CHECK_CLUST(newclust, mydata->fatsize)) { + debug("newclust: 0x%x\n", newclust); + debug("Invalid FAT entry\n"); + return 0; + } + endclust = newclust; + actsize += bytesperclust; + } + + /* set remaining bytes */ + actsize = filesize; + if (set_cluster(mydata, curclust, buffer, (u32)actsize) != 0) { + debug("error: writing cluster\n"); + return -1; + } + *gotsize += actsize; + + /* Mark end of file in FAT */ + if (mydata->fatsize == 12) + newclust = 0xfff; + else if (mydata->fatsize == 16) + newclust = 0xffff; + else if (mydata->fatsize == 32) + newclust = 0xfffffff; + set_fatent_value(mydata, endclust, newclust); + + return 0; +getit: + if (set_cluster(mydata, curclust, buffer, (u32)actsize) != 0) { + debug("error: writing cluster\n"); + return -1; + } + *gotsize += actsize; + filesize -= actsize; + buffer += actsize; + + if (CHECK_CLUST(newclust, mydata->fatsize)) { + debug("newclust: 0x%x\n", newclust); + debug("Invalid FAT entry\n"); + return 0; + } + actsize = bytesperclust; + curclust = endclust = newclust; + } while (1); + + return 0; +} + +/** + * fill_dentry() - fill directory entry with shortname + * + * @mydata: private filesystem parameters + * @dentptr: directory entry + * @shortname: chosen short name + * @start_cluster: first cluster of file + * @size: file size + * @attr: file attributes + */ +static void fill_dentry(fsdata *mydata, dir_entry *dentptr, + const char *shortname, __u32 start_cluster, __u32 size, __u8 attr) +{ + memset(dentptr, 0, sizeof(*dentptr)); + + set_start_cluster(mydata, dentptr, start_cluster); + dentptr->size = cpu_to_le32(size); + + dentptr->attr = attr; + + memcpy(&dentptr->nameext, shortname, SHORT_NAME_SIZE); +} + +/** + * find_directory_entry() - find a directory entry by filename + * + * @itr: directory iterator + * @filename: name of file to find + * Return: directory entry or NULL + */ +static dir_entry *find_directory_entry(fat_itr *itr, char *filename) +{ + int match = 0; + + while (fat_itr_next(itr)) { + /* check both long and short name: */ + if (!strcasecmp(filename, itr->name)) + match = 1; + else if (itr->name != itr->s_name && + !strcasecmp(filename, itr->s_name)) + match = 1; + + if (!match) + continue; + + if (itr->dent->nameext.name[0] == '\0') + return NULL; + else + return itr->dent; + } + + return NULL; +} + +static int split_filename(char *filename, char **dirname, char **basename) +{ + char *p, *last_slash, *last_slash_cont; + +again: + p = filename; + last_slash = NULL; + last_slash_cont = NULL; + while (*p) { + if (ISDIRDELIM(*p)) { + last_slash = p; + last_slash_cont = p; + /* continuous slashes */ + while (ISDIRDELIM(*p)) + last_slash_cont = p++; + if (!*p) + break; + } + p++; + } + + if (last_slash) { + if (last_slash_cont == (filename + strlen(filename) - 1)) { + /* remove trailing slashes */ + *last_slash = '\0'; + goto again; + } + + if (last_slash == filename) { + /* avoid ""(null) directory */ + *dirname = "/"; + } else { + *last_slash = '\0'; + *dirname = filename; + } + + *last_slash_cont = '\0'; + filename = last_slash_cont + 1; + } else { + *dirname = "/"; /* root by default */ + } + + /* + * The FAT32 File System Specification v1.03 requires leading and + * trailing spaces as well as trailing periods to be ignored. + */ + for (; *filename == ' '; ++filename) + ; + + /* Keep special entries '.' and '..' */ + if (filename[0] == '.' && + (!filename[1] || (filename[1] == '.' && !filename[2]))) + goto done; + + /* Remove trailing periods and spaces */ + for (p = filename + strlen(filename) - 1; p >= filename; --p) { + switch (*p) { + case ' ': + case '.': + *p = 0; + break; + default: + goto done; + } + } + +done: + *basename = filename; + + return 0; +} + +/** + * normalize_longname() - check long file name and convert to lower case + * + * We assume here that the FAT file system is using an 8bit code page. + * Linux typically uses CP437, EDK2 assumes CP1250. + * + * @l_filename: preallocated buffer receiving the normalized name + * @filename: filename to normalize + * Return: 0 on success, -1 on failure + */ +static int normalize_longname(char *l_filename, const char *filename) +{ + const char *p, illegal[] = "<>:\"/\\|?*"; + size_t len; + + len = strlen(filename); + if (!len || len >= VFAT_MAXLEN_BYTES || filename[len - 1] == '.') + return -1; + + for (p = filename; *p; ++p) { + if ((unsigned char)*p < 0x20) + return -1; + if (strchr(illegal, *p)) + return -1; + } + + strcpy(l_filename, filename); + downcase(l_filename, VFAT_MAXLEN_BYTES); + + return 0; +} + +int file_fat_write_at(const char *filename, loff_t pos, void *buffer, + loff_t size, loff_t *actwrite) +{ + dir_entry *retdent; + fsdata datablock = { .fatbuf = NULL, }; + fsdata *mydata = &datablock; + fat_itr *itr = NULL; + int ret = -1; + char *filename_copy, *parent, *basename; + char l_filename[VFAT_MAXLEN_BYTES]; + + debug("writing %s\n", filename); + + filename_copy = strdup(filename); + if (!filename_copy) + return -ENOMEM; + + split_filename(filename_copy, &parent, &basename); + if (!strlen(basename)) { + ret = -EINVAL; + goto exit; + } + + if (normalize_longname(l_filename, basename)) { + printf("FAT: illegal filename (%s)\n", basename); + ret = -EINVAL; + goto exit; + } + + itr = malloc_cache_aligned(sizeof(fat_itr)); + if (!itr) { + ret = -ENOMEM; + goto exit; + } + + ret = fat_itr_root(itr, &datablock); + if (ret) + goto exit; + + total_sector = datablock.total_sect; + + ret = fat_itr_resolve(itr, parent, TYPE_DIR); + if (ret) { + printf("%s: doesn't exist (%d)\n", parent, ret); + goto exit; + } + + retdent = find_directory_entry(itr, l_filename); + + if (retdent) { + if (fat_itr_isdir(itr)) { + ret = -EISDIR; + goto exit; + } + + /* A file exists */ + if (pos == -1) + /* Append to the end */ + pos = FAT2CPU32(retdent->size); + if (pos > retdent->size) { + /* No hole allowed */ + ret = -EINVAL; + goto exit; + } + + /* Update file size in a directory entry */ + retdent->size = cpu_to_le32(pos + size); + } else { + /* Create a new file */ + char shortname[SHORT_NAME_SIZE]; + int ndent; + + if (pos) { + /* No hole allowed */ + ret = -EINVAL; + goto exit; + } + + /* Check if long name is needed */ + ndent = set_name(itr, basename, shortname); + if (ndent < 0) { + ret = ndent; + goto exit; + } + ret = fat_find_empty_dentries(itr, ndent); + if (ret) + goto exit; + if (ndent > 1) { + /* Set long name entries */ + ret = fill_dir_slot(itr, basename, shortname); + if (ret) + goto exit; + } + + /* Set short name entry */ + fill_dentry(itr->fsdata, itr->dent, shortname, 0, size, + ATTR_ARCH); + + retdent = itr->dent; + } + + ret = set_contents(mydata, retdent, pos, buffer, size, actwrite); + if (ret < 0) { + printf("Error: writing contents\n"); + ret = -EIO; + goto exit; + } + debug("attempt to write 0x%llx bytes\n", *actwrite); + + /* Flush fat buffer */ + ret = flush_dirty_fat_buffer(mydata); + if (ret) { + printf("Error: flush fat buffer\n"); + ret = -EIO; + goto exit; + } + + /* Write directory table to device */ + ret = flush_dir(itr); + +exit: + free(filename_copy); + free(mydata->fatbuf); + free(itr); + return ret; +} + +int file_fat_write(const char *filename, void *buffer, loff_t offset, + loff_t maxsize, loff_t *actwrite) +{ + return file_fat_write_at(filename, offset, buffer, maxsize, actwrite); +} + +static int fat_dir_entries(fat_itr *itr) +{ + fat_itr *dirs; + fsdata fsdata = { .fatbuf = NULL, }, *mydata = &fsdata; + /* for FATBUFSIZE */ + int count; + + dirs = malloc_cache_aligned(sizeof(fat_itr)); + if (!dirs) { + debug("Error: allocating memory\n"); + count = -ENOMEM; + goto exit; + } + + /* duplicate fsdata */ + fat_itr_child(dirs, itr); + fsdata = *dirs->fsdata; + + /* allocate local fat buffer */ + fsdata.fatbuf = malloc_cache_aligned(FATBUFSIZE); + if (!fsdata.fatbuf) { + debug("Error: allocating memory\n"); + count = -ENOMEM; + goto exit; + } + fsdata.fatbufnum = -1; + dirs->fsdata = &fsdata; + + for (count = 0; fat_itr_next(dirs); count++) + ; + +exit: + free(fsdata.fatbuf); + free(dirs); + return count; +} + +/** + * delete_single_dentry() - delete a single directory entry + * + * @itr: directory iterator + * Return: 0 for success + */ +static int delete_single_dentry(fat_itr *itr) +{ + struct dir_entry *dent = itr->dent; + + memset(dent, 0, sizeof(*dent)); + dent->nameext.name[0] = DELETED_FLAG; + + if (!itr->remaining) + return flush_dir(itr); + return 0; +} + +/** + * delete_long_name() - delete long name directory entries + * + * @itr: directory iterator + * Return: 0 for success + */ +static int delete_long_name(fat_itr *itr) +{ + int seqn = itr->dent->nameext.name[0] & ~LAST_LONG_ENTRY_MASK; + + while (seqn--) { + struct dir_entry *dent; + int ret; + + ret = delete_single_dentry(itr); + if (ret) + return ret; + dent = next_dent(itr); + if (!dent) + return -EIO; + } + return 0; +} + +/** + * delete_dentry_long() - remove directory entry + * + * @itr: directory iterator + * Return: 0 for success + */ +static int delete_dentry_long(fat_itr *itr) +{ + fsdata *mydata = itr->fsdata; + dir_entry *dent = itr->dent; + + /* free cluster blocks */ + clear_fatent(mydata, START(dent)); + if (flush_dirty_fat_buffer(mydata) < 0) { + printf("Error: flush fat buffer\n"); + return -EIO; + } + /* Position to first directory entry for long name */ + if (itr->clust != itr->dent_clust) { + int ret; + + ret = fat_move_to_cluster(itr, itr->dent_clust); + if (ret) + return ret; + } + itr->dent = itr->dent_start; + itr->remaining = itr->dent_rem; + dent = itr->dent_start; + /* Delete long name */ + if ((dent->attr & ATTR_VFAT) == ATTR_VFAT && + (dent->nameext.name[0] & LAST_LONG_ENTRY_MASK)) { + int ret; + + ret = delete_long_name(itr); + if (ret) + return ret; + } + /* Delete short name */ + delete_single_dentry(itr); + return flush_dir(itr); +} + +int fat_unlink(const char *filename) +{ + fsdata fsdata = { .fatbuf = NULL, }; + fat_itr *itr = NULL; + int n_entries, ret; + char *filename_copy, *dirname, *basename; + + filename_copy = strdup(filename); + if (!filename_copy) { + printf("Error: allocating memory\n"); + ret = -ENOMEM; + goto exit; + } + split_filename(filename_copy, &dirname, &basename); + + if (!strcmp(dirname, "/") && !strcmp(basename, "")) { + printf("Error: cannot remove root\n"); + ret = -EINVAL; + goto exit; + } + + itr = malloc_cache_aligned(sizeof(fat_itr)); + if (!itr) { + printf("Error: allocating memory\n"); + ret = -ENOMEM; + goto exit; + } + + ret = fat_itr_root(itr, &fsdata); + if (ret) + goto exit; + + total_sector = fsdata.total_sect; + + ret = fat_itr_resolve(itr, dirname, TYPE_DIR); + if (ret) { + printf("%s: doesn't exist (%d)\n", dirname, ret); + ret = -ENOENT; + goto exit; + } + + if (!find_directory_entry(itr, basename)) { + printf("%s: doesn't exist\n", basename); + ret = -ENOENT; + goto exit; + } + + if (fat_itr_isdir(itr)) { + n_entries = fat_dir_entries(itr); + if (n_entries < 0) { + ret = n_entries; + goto exit; + } + if (n_entries > 2) { + printf("Error: directory is not empty: %d\n", + n_entries); + ret = -EINVAL; + goto exit; + } + } + + ret = delete_dentry_long(itr); + +exit: + free(fsdata.fatbuf); + free(itr); + free(filename_copy); + + return ret; +} + +int fat_mkdir(const char *dirname) +{ + dir_entry *retdent; + fsdata datablock = { .fatbuf = NULL, }; + fsdata *mydata = &datablock; + fat_itr *itr = NULL; + char *dirname_copy, *parent, *basename; + char l_dirname[VFAT_MAXLEN_BYTES]; + int ret = -1; + loff_t actwrite; + unsigned int bytesperclust; + dir_entry *dotdent = NULL; + + dirname_copy = strdup(dirname); + if (!dirname_copy) + goto exit; + + split_filename(dirname_copy, &parent, &basename); + if (!strlen(basename)) { + ret = -EINVAL; + goto exit; + } + + if (normalize_longname(l_dirname, basename)) { + printf("FAT: illegal filename (%s)\n", basename); + ret = -EINVAL; + goto exit; + } + + itr = malloc_cache_aligned(sizeof(fat_itr)); + if (!itr) { + ret = -ENOMEM; + goto exit; + } + + ret = fat_itr_root(itr, &datablock); + if (ret) + goto exit; + + total_sector = datablock.total_sect; + + ret = fat_itr_resolve(itr, parent, TYPE_DIR); + if (ret) { + printf("%s: doesn't exist (%d)\n", parent, ret); + goto exit; + } + + retdent = find_directory_entry(itr, l_dirname); + + if (retdent) { + printf("%s: already exists\n", l_dirname); + ret = -EEXIST; + goto exit; + } else { + char shortname[SHORT_NAME_SIZE]; + int ndent; + + if (itr->is_root) { + /* root dir cannot have "." or ".." */ + if (!strcmp(l_dirname, ".") || + !strcmp(l_dirname, "..")) { + ret = -EINVAL; + goto exit; + } + } + + /* Check if long name is needed */ + ndent = set_name(itr, basename, shortname); + if (ndent < 0) { + ret = ndent; + goto exit; + } + ret = fat_find_empty_dentries(itr, ndent); + if (ret) + goto exit; + if (ndent > 1) { + /* Set long name entries */ + ret = fill_dir_slot(itr, basename, shortname); + if (ret) + goto exit; + } + + /* Set attribute as archive for regular file */ + fill_dentry(itr->fsdata, itr->dent, shortname, 0, 0, + ATTR_DIR | ATTR_ARCH); + + retdent = itr->dent; + } + + /* Default entries */ + bytesperclust = mydata->clust_size * mydata->sect_size; + dotdent = malloc_cache_aligned(bytesperclust); + if (!dotdent) { + ret = -ENOMEM; + goto exit; + } + memset(dotdent, 0, bytesperclust); + + memcpy(&dotdent[0].nameext, ". ", 11); + dotdent[0].attr = ATTR_DIR | ATTR_ARCH; + + memcpy(&dotdent[1].nameext, ".. ", 11); + dotdent[1].attr = ATTR_DIR | ATTR_ARCH; + + if (itr->is_root) + set_start_cluster(mydata, &dotdent[1], 0); + else + set_start_cluster(mydata, &dotdent[1], itr->start_clust); + + ret = set_contents(mydata, retdent, 0, (__u8 *)dotdent, + bytesperclust, &actwrite); + if (ret < 0) { + printf("Error: writing contents\n"); + goto exit; + } + /* Write twice for "." */ + set_start_cluster(mydata, &dotdent[0], START(retdent)); + ret = set_contents(mydata, retdent, 0, (__u8 *)dotdent, + bytesperclust, &actwrite); + if (ret < 0) { + printf("Error: writing contents\n"); + goto exit; + } + + /* Flush fat buffer */ + ret = flush_dirty_fat_buffer(mydata); + if (ret) { + printf("Error: flush fat buffer\n"); + ret = -EIO; + goto exit; + } + + /* Write directory table to device */ + ret = flush_dir(itr); + +exit: + free(dirname_copy); + free(mydata->fatbuf); + free(itr); + free(dotdent); + return ret; +} |