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- // 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 <fat.h>
- #include <log.h>
- #include <malloc.h>
- #include <asm/byteorder.h>
- #include <part.h>
- #include <asm/cache.h>
- #include <linux/ctype.h>
- #include <div64.h>
- #include <linux/math64.h>
- #include "fat.c"
- static void uppercase(char *str, int len)
- {
- int i;
- for (i = 0; i < len; i++) {
- *str = toupper(*str);
- str++;
- }
- }
- 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;
- }
- /**
- * set_name() - set short name in directory entry
- *
- * @dirent: directory entry
- * @filename: long file name
- */
- static void set_name(dir_entry *dirent, const char *filename)
- {
- char s_name[VFAT_MAXLEN_BYTES];
- char *period;
- int period_location, len, i, ext_num;
- if (filename == NULL)
- return;
- len = strlen(filename);
- if (len == 0)
- return;
- strncpy(s_name, filename, VFAT_MAXLEN_BYTES - 1);
- s_name[VFAT_MAXLEN_BYTES - 1] = '\0';
- uppercase(s_name, len);
- period = strchr(s_name, '.');
- if (period == NULL) {
- period_location = len;
- ext_num = 0;
- } else {
- period_location = period - s_name;
- ext_num = len - period_location - 1;
- }
- /* Pad spaces when the length of file name is shorter than eight */
- if (period_location < 8) {
- memcpy(dirent->name, s_name, period_location);
- for (i = period_location; i < 8; i++)
- dirent->name[i] = ' ';
- } else if (period_location == 8) {
- memcpy(dirent->name, s_name, period_location);
- } else {
- memcpy(dirent->name, s_name, 6);
- /*
- * TODO: Translating two long names with the same first six
- * characters to the same short name is utterly wrong.
- * Short names must be unique.
- */
- dirent->name[6] = '~';
- dirent->name[7] = '1';
- }
- if (ext_num < 3) {
- memcpy(dirent->ext, s_name + period_location + 1, ext_num);
- for (i = ext_num; i < 3; i++)
- dirent->ext[i] = ' ';
- } else
- memcpy(dirent->ext, s_name + period_location + 1, 3);
- debug("name : %s\n", dirent->name);
- debug("ext : %s\n", dirent->ext);
- }
- /*
- * 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;
- }
- /*
- * 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 new_dir_table(fat_itr *itr);
- static int flush_dir(fat_itr *itr);
- /*
- * Fill dir_slot entries with appropriate name, id, and attr
- * 'itr' will point to a next entry
- */
- static int
- fill_dir_slot(fat_itr *itr, const char *l_name)
- {
- __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(itr->dent->name, itr->dent->ext);
- 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 == 0)
- flush_dir(itr);
- /* allocate a cluster for more entries */
- if (!fat_itr_next(itr))
- if (!itr->dent &&
- (!itr->is_root || itr->fsdata->fatsize == 32) &&
- new_dir_table(itr))
- return -1;
- }
- 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)
- {
- u32 nsects = 0;
- 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) {
- 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);
- }
- static int
- flush_dir(fat_itr *itr)
- {
- fsdata *mydata = itr->fsdata;
- u32 startsect, sect_offset, nsects;
- if (!itr->is_root || mydata->fatsize == 32)
- return set_cluster(mydata, itr->clust, itr->block,
- mydata->clust_size * mydata->sect_size);
- 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);
- return set_sectors(mydata, startsect, itr->block,
- nsects * mydata->sect_size);
- }
- /*
- * 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;
- buffer += 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;
- }
- /*
- * Allocate a cluster for additional directory entries
- */
- static int new_dir_table(fat_itr *itr)
- {
- fsdata *mydata = itr->fsdata;
- int dir_newclust = 0;
- unsigned int bytesperclust = mydata->clust_size * mydata->sect_size;
- dir_newclust = find_empty_cluster(mydata);
- set_fatent_value(mydata, itr->clust, 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);
- itr->clust = dir_newclust;
- itr->next_clust = dir_newclust;
- if (flush_dirty_fat_buffer(mydata) < 0)
- return -1;
- memset(itr->block, 0x00, bytesperclust);
- 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 dir_entry
- */
- static void fill_dentry(fsdata *mydata, dir_entry *dentptr,
- const char *filename, __u32 start_cluster, __u32 size, __u8 attr)
- {
- set_start_cluster(mydata, dentptr, start_cluster);
- dentptr->size = cpu_to_le32(size);
- dentptr->attr = attr;
- set_name(dentptr, filename);
- }
- /*
- * Find a directory entry based on filename or start cluster number
- * If the directory entry is not found,
- * the new position for writing a directory entry will be returned
- */
- 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->name[0] == '\0')
- return NULL;
- else
- return itr->dent;
- }
- /* allocate a cluster for more entries */
- if (!itr->dent &&
- (!itr->is_root || itr->fsdata->fatsize == 32) &&
- new_dir_table(itr))
- /* indicate that allocating dent failed */
- itr->dent = NULL;
- 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';
- *basename = last_slash_cont + 1;
- } else {
- *dirname = "/"; /* root by default */
- *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[] = "<>:\"/\\|?*";
- if (strlen(filename) >= VFAT_MAXLEN_BYTES)
- 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;
- }
- filename = basename;
- if (normalize_longname(l_filename, filename)) {
- printf("FAT: illegal filename (%s)\n", filename);
- 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 */
- if (itr->is_root) {
- /* root dir cannot have "." or ".." */
- if (!strcmp(l_filename, ".") ||
- !strcmp(l_filename, "..")) {
- ret = -EINVAL;
- goto exit;
- }
- }
- if (!itr->dent) {
- printf("Error: allocating new dir entry\n");
- ret = -EIO;
- goto exit;
- }
- if (pos) {
- /* No hole allowed */
- ret = -EINVAL;
- goto exit;
- }
- memset(itr->dent, 0, sizeof(*itr->dent));
- /* Calculate checksum for short name */
- set_name(itr->dent, filename);
- /* Set long name entries */
- if (fill_dir_slot(itr, filename)) {
- ret = -EIO;
- goto exit;
- }
- /* Set short name entry */
- fill_dentry(itr->fsdata, itr->dent, filename, 0, size, 0x20);
- 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);
- if (ret) {
- printf("Error: writing directory entry\n");
- ret = -EIO;
- }
- 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;
- }
- static int delete_dentry(fat_itr *itr)
- {
- fsdata *mydata = itr->fsdata;
- dir_entry *dentptr = itr->dent;
- /* free cluster blocks */
- clear_fatent(mydata, START(dentptr));
- if (flush_dirty_fat_buffer(mydata) < 0) {
- printf("Error: flush fat buffer\n");
- return -EIO;
- }
- /*
- * update a directory entry
- * TODO:
- * - long file name support
- * - find and mark the "new" first invalid entry as name[0]=0x00
- */
- memset(dentptr, 0, sizeof(*dentptr));
- dentptr->name[0] = 0xe5;
- if (flush_dir(itr)) {
- printf("error: writing directory entry\n");
- return -EIO;
- }
- return 0;
- }
- 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(itr);
- exit:
- free(fsdata.fatbuf);
- free(itr);
- free(filename_copy);
- return ret;
- }
- int fat_mkdir(const char *new_dirname)
- {
- dir_entry *retdent;
- fsdata datablock = { .fatbuf = NULL, };
- fsdata *mydata = &datablock;
- fat_itr *itr = NULL;
- char *dirname_copy, *parent, *dirname;
- char l_dirname[VFAT_MAXLEN_BYTES];
- int ret = -1;
- loff_t actwrite;
- unsigned int bytesperclust;
- dir_entry *dotdent = NULL;
- dirname_copy = strdup(new_dirname);
- if (!dirname_copy)
- goto exit;
- split_filename(dirname_copy, &parent, &dirname);
- if (!strlen(dirname)) {
- ret = -EINVAL;
- goto exit;
- }
- if (normalize_longname(l_dirname, dirname)) {
- printf("FAT: illegal filename (%s)\n", dirname);
- 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 {
- if (itr->is_root) {
- /* root dir cannot have "." or ".." */
- if (!strcmp(l_dirname, ".") ||
- !strcmp(l_dirname, "..")) {
- ret = -EINVAL;
- goto exit;
- }
- }
- if (!itr->dent) {
- printf("Error: allocating new dir entry\n");
- ret = -EIO;
- goto exit;
- }
- memset(itr->dent, 0, sizeof(*itr->dent));
- /* Set short name to set alias checksum field in dir_slot */
- set_name(itr->dent, dirname);
- fill_dir_slot(itr, dirname);
- /* Set attribute as archive for regular file */
- fill_dentry(itr->fsdata, itr->dent, dirname, 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].name, ". ", 8);
- memcpy(dotdent[0].ext, " ", 3);
- dotdent[0].attr = ATTR_DIR | ATTR_ARCH;
- memcpy(dotdent[1].name, ".. ", 8);
- memcpy(dotdent[1].ext, " ", 3);
- dotdent[1].attr = ATTR_DIR | ATTR_ARCH;
- 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");
- goto exit;
- }
- /* Write directory table to device */
- ret = flush_dir(itr);
- if (ret)
- printf("Error: writing directory entry\n");
- exit:
- free(dirname_copy);
- free(mydata->fatbuf);
- free(itr);
- free(dotdent);
- return ret;
- }
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