summaryrefslogtreecommitdiffstats
path: root/fs/fat
diff options
context:
space:
mode:
authorDonggeun Kim <dg77.kim@samsung.com>2011-10-24 21:15:28 +0000
committerWolfgang Denk <wd@denx.de>2011-10-26 21:40:44 +0200
commitc30a15e590c7e5bfd27e4704c81648071f11d51f (patch)
tree3dfb06047dccb50fbf1555ff48a5396ea5317488 /fs/fat
parenteea63e05d0b7f54e7aa39725015483972c71cb3c (diff)
downloadtalos-obmc-uboot-c30a15e590c7e5bfd27e4704c81648071f11d51f.tar.gz
talos-obmc-uboot-c30a15e590c7e5bfd27e4704c81648071f11d51f.zip
FAT: Add FAT write feature
In some cases, saving data in RAM as a file with FAT format is required. This patch allows the file to be written in FAT formatted partition. The usage is similar with reading a file. First, fat_register_device function is called before file_fat_write function in order to set target partition. Then, file_fat_write function is invoked with desired file name, start ram address for writing data, and file size. Signed-off-by: Donggeun Kim <dg77.kim@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Diffstat (limited to 'fs/fat')
-rw-r--r--fs/fat/Makefile1
-rw-r--r--fs/fat/fat.c2
-rw-r--r--fs/fat/fat_write.c1090
3 files changed, 1093 insertions, 0 deletions
diff --git a/fs/fat/Makefile b/fs/fat/Makefile
index 93b6f07389..9635d36fcf 100644
--- a/fs/fat/Makefile
+++ b/fs/fat/Makefile
@@ -25,6 +25,7 @@ LIB = $(obj)libfat.o
AOBJS =
COBJS-$(CONFIG_CMD_FAT) := fat.o
+COBJS-$(CONFIG_FAT_WRITE):= fat_write.o
ifndef CONFIG_SPL_BUILD
COBJS-$(CONFIG_CMD_FAT) += file.o
diff --git a/fs/fat/fat.c b/fs/fat/fat.c
index 756ac64a8b..7cf173caaa 100644
--- a/fs/fat/fat.c
+++ b/fs/fat/fat.c
@@ -46,6 +46,7 @@ static void downcase (char *str)
static block_dev_desc_t *cur_dev = NULL;
static unsigned long part_offset = 0;
+static unsigned long part_size;
static int cur_part = 1;
@@ -99,6 +100,7 @@ int fat_register_device (block_dev_desc_t * dev_desc, int part_no)
if (!get_partition_info(dev_desc, part_no, &info)) {
part_offset = info.start;
cur_part = part_no;
+ part_size = info.size;
} else if ((strncmp((char *)&buffer[DOS_FS_TYPE_OFFSET], "FAT", 3) == 0) ||
(strncmp((char *)&buffer[DOS_FS32_TYPE_OFFSET], "FAT32", 5) == 0)) {
/* ok, we assume we are on a PBR only */
diff --git a/fs/fat/fat_write.c b/fs/fat/fat_write.c
new file mode 100644
index 0000000000..4f1772f29a
--- /dev/null
+++ b/fs/fat/fat_write.c
@@ -0,0 +1,1090 @@
+/*
+ * fat_write.c
+ *
+ * R/W (V)FAT 12/16/32 filesystem implementation by Donggeun Kim
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+#include <command.h>
+#include <config.h>
+#include <fat.h>
+#include <asm/byteorder.h>
+#include <part.h>
+#include "fat.c"
+
+static void uppercase(char *str, int len)
+{
+ int i;
+
+ for (i = 0; i < len; i++) {
+ TOUPPER(*str);
+ str++;
+ }
+}
+
+static int total_sector;
+static int disk_write(__u32 startblock, __u32 getsize, __u8 *bufptr)
+{
+ if (cur_dev == NULL)
+ return -1;
+
+ if (startblock + getsize > total_sector) {
+ printf("error: overflow occurs\n");
+ return -1;
+ }
+
+ startblock += part_offset;
+
+ if (cur_dev->block_read) {
+ return cur_dev->block_write(cur_dev->dev, startblock, getsize,
+ (unsigned long *) bufptr);
+ }
+ return -1;
+}
+
+/*
+ * Set short name in directory entry
+ */
+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;
+
+ memcpy(s_name, filename, len);
+ 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);
+ 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_fat_buffer(fsdata *mydata)
+{
+ int getsize = FATBUFBLOCKS;
+ __u32 fatlength = mydata->fatlength;
+ __u8 *bufptr = mydata->fatbuf;
+ __u32 startblock = mydata->fatbufnum * FATBUFBLOCKS;
+
+ fatlength *= mydata->sect_size;
+ startblock += mydata->fat_sect;
+
+ if (getsize > fatlength)
+ getsize = fatlength;
+
+ /* Write FAT buf */
+ if (disk_write(startblock, getsize, bufptr) < 0) {
+ debug("error: writing FAT blocks\n");
+ return -1;
+ }
+
+ return 0;
+}
+
+/*
+ * Get the entry at index 'entry' in a FAT (12/16/32) table.
+ * On failure 0x00 is returned.
+ * When bufnum is changed, write back the previous fatbuf to the disk.
+ */
+static __u32 get_fatent_value(fsdata *mydata, __u32 entry)
+{
+ __u32 bufnum;
+ __u32 off16, offset;
+ __u32 ret = 0x00;
+ __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 ret;
+ }
+
+ debug("FAT%d: entry: 0x%04x = %d, offset: 0x%04x = %d\n",
+ mydata->fatsize, entry, entry, offset, offset);
+
+ /* 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;
+
+ if (getsize > fatlength)
+ getsize = fatlength;
+
+ fatlength *= mydata->sect_size; /* We want it in bytes now */
+ startblock += mydata->fat_sect; /* Offset from start of disk */
+
+ /* Write back the fatbuf to the disk */
+ if (mydata->fatbufnum != -1) {
+ if (flush_fat_buffer(mydata) < 0)
+ return -1;
+ }
+
+ if (disk_read(startblock, getsize, bufptr) < 0) {
+ debug("Error reading FAT blocks\n");
+ return ret;
+ }
+ mydata->fatbufnum = bufnum;
+ }
+
+ /* Get the actual entry from the table */
+ switch (mydata->fatsize) {
+ case 32:
+ ret = FAT2CPU32(((__u32 *) mydata->fatbuf)[offset]);
+ break;
+ case 16:
+ ret = FAT2CPU16(((__u16 *) mydata->fatbuf)[offset]);
+ break;
+ case 12:
+ off16 = (offset * 3) / 4;
+
+ switch (offset & 0x3) {
+ case 0:
+ ret = FAT2CPU16(((__u16 *) mydata->fatbuf)[off16]);
+ ret &= 0xfff;
+ break;
+ case 1:
+ val1 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
+ val1 &= 0xf000;
+ val2 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]);
+ val2 &= 0x00ff;
+ ret = (val2 << 4) | (val1 >> 12);
+ break;
+ case 2:
+ val1 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
+ val1 &= 0xff00;
+ val2 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]);
+ val2 &= 0x000f;
+ ret = (val2 << 8) | (val1 >> 8);
+ break;
+ case 3:
+ ret = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
+ ret = (ret & 0xfff0) >> 4;
+ break;
+ default:
+ break;
+ }
+ break;
+ }
+ debug("FAT%d: ret: %08x, entry: %08x, offset: %04x\n",
+ mydata->fatsize, ret, entry, offset);
+
+ return ret;
+}
+
+#ifdef CONFIG_SUPPORT_VFAT
+/*
+ * 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 is_next_clust(fsdata *mydata, dir_entry *dentptr);
+static void flush_dir_table(fsdata *mydata, dir_entry **dentptr);
+
+/*
+ * Fill dir_slot entries with appropriate name, id, and attr
+ * The real directory entry is returned by 'dentptr'
+ */
+static void
+fill_dir_slot(fsdata *mydata, dir_entry **dentptr, const char *l_name)
+{
+ dir_slot *slotptr = (dir_slot *)get_vfatname_block;
+ __u8 counter, checksum;
+ int idx = 0, ret;
+ char s_name[16];
+
+ /* Get short file name and checksum value */
+ strncpy(s_name, (*dentptr)->name, 16);
+ checksum = mkcksum(s_name);
+
+ 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) {
+ if (is_next_clust(mydata, *dentptr)) {
+ /* A new cluster is allocated for directory table */
+ flush_dir_table(mydata, dentptr);
+ }
+ memcpy(*dentptr, slotptr, sizeof(dir_slot));
+ (*dentptr)++;
+ slotptr--;
+ counter--;
+ }
+
+ if (is_next_clust(mydata, *dentptr)) {
+ /* A new cluster is allocated for directory table */
+ flush_dir_table(mydata, dentptr);
+ }
+}
+
+static __u32 dir_curclust;
+
+/*
+ * Extract the full long filename starting at 'retdent' (which is really
+ * a slot) into 'l_name'. If successful also copy the real directory entry
+ * into 'retdent'
+ * If additional adjacent cluster for directory entries is read into memory,
+ * then 'get_vfatname_block' is copied into 'get_dentfromdir_block' and
+ * the location of the real directory entry is returned by 'retdent'
+ * Return 0 on success, -1 otherwise.
+ */
+static int
+get_long_file_name(fsdata *mydata, int curclust, __u8 *cluster,
+ dir_entry **retdent, char *l_name)
+{
+ dir_entry *realdent;
+ dir_slot *slotptr = (dir_slot *)(*retdent);
+ dir_slot *slotptr2 = NULL;
+ __u8 *buflimit = cluster + mydata->sect_size * ((curclust == 0) ?
+ PREFETCH_BLOCKS :
+ mydata->clust_size);
+ __u8 counter = (slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff;
+ int idx = 0, cur_position = 0;
+
+ if (counter > VFAT_MAXSEQ) {
+ debug("Error: VFAT name is too long\n");
+ return -1;
+ }
+
+ while ((__u8 *)slotptr < buflimit) {
+ if (counter == 0)
+ break;
+ if (((slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff) != counter)
+ return -1;
+ slotptr++;
+ counter--;
+ }
+
+ if ((__u8 *)slotptr >= buflimit) {
+ if (curclust == 0)
+ return -1;
+ curclust = get_fatent_value(mydata, dir_curclust);
+ if (CHECK_CLUST(curclust, mydata->fatsize)) {
+ debug("curclust: 0x%x\n", curclust);
+ printf("Invalid FAT entry\n");
+ return -1;
+ }
+
+ dir_curclust = curclust;
+
+ if (get_cluster(mydata, curclust, get_vfatname_block,
+ mydata->clust_size * mydata->sect_size) != 0) {
+ debug("Error: reading directory block\n");
+ return -1;
+ }
+
+ slotptr2 = (dir_slot *)get_vfatname_block;
+ while (counter > 0) {
+ if (((slotptr2->id & ~LAST_LONG_ENTRY_MASK)
+ & 0xff) != counter)
+ return -1;
+ slotptr2++;
+ counter--;
+ }
+
+ /* Save the real directory entry */
+ realdent = (dir_entry *)slotptr2;
+ while ((__u8 *)slotptr2 > get_vfatname_block) {
+ slotptr2--;
+ slot2str(slotptr2, l_name, &idx);
+ }
+ } else {
+ /* Save the real directory entry */
+ realdent = (dir_entry *)slotptr;
+ }
+
+ do {
+ slotptr--;
+ if (slot2str(slotptr, l_name, &idx))
+ break;
+ } while (!(slotptr->id & LAST_LONG_ENTRY_MASK));
+
+ l_name[idx] = '\0';
+ if (*l_name == DELETED_FLAG)
+ *l_name = '\0';
+ else if (*l_name == aRING)
+ *l_name = DELETED_FLAG;
+ downcase(l_name);
+
+ /* Return the real directory entry */
+ *retdent = realdent;
+
+ if (slotptr2) {
+ memcpy(get_dentfromdir_block, get_vfatname_block,
+ mydata->clust_size * mydata->sect_size);
+ cur_position = (__u8 *)realdent - get_vfatname_block;
+ *retdent = (dir_entry *) &get_dentfromdir_block[cur_position];
+ }
+
+ return 0;
+}
+
+#endif
+
+/*
+ * Set the entry at index 'entry' in a FAT (16/32) table.
+ */
+static int set_fatent_value(fsdata *mydata, __u32 entry, __u32 entry_value)
+{
+ __u32 bufnum, offset;
+
+ switch (mydata->fatsize) {
+ case 32:
+ bufnum = entry / FAT32BUFSIZE;
+ offset = entry - bufnum * FAT32BUFSIZE;
+ break;
+ case 16:
+ bufnum = entry / FAT16BUFSIZE;
+ offset = entry - bufnum * FAT16BUFSIZE;
+ 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;
+
+ fatlength *= mydata->sect_size;
+ startblock += mydata->fat_sect;
+
+ if (getsize > fatlength)
+ getsize = fatlength;
+
+ if (mydata->fatbufnum != -1) {
+ if (flush_fat_buffer(mydata) < 0)
+ return -1;
+ }
+
+ if (disk_read(startblock, getsize, bufptr) < 0) {
+ debug("Error reading FAT blocks\n");
+ return -1;
+ }
+ mydata->fatbufnum = bufnum;
+ }
+
+ /* 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;
+ default:
+ return -1;
+ }
+
+ return 0;
+}
+
+/*
+ * Determine the entry value at index 'entry' in a FAT (16/32) table
+ */
+static __u32 determine_fatent(fsdata *mydata, __u32 entry)
+{
+ __u32 next_fat, next_entry = entry + 1;
+
+ while (1) {
+ next_fat = get_fatent_value(mydata, next_entry);
+ if (next_fat == 0) {
+ 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;
+}
+
+/*
+ * Write at most 'size' bytes from 'buffer' into the specified cluster.
+ * Return 0 on success, -1 otherwise.
+ */
+static int
+set_cluster(fsdata *mydata, __u32 clustnum, __u8 *buffer,
+ unsigned long size)
+{
+ int idx = 0;
+ __u32 startsect;
+
+ if (clustnum > 0)
+ startsect = mydata->data_begin +
+ clustnum * mydata->clust_size;
+ else
+ startsect = mydata->rootdir_sect;
+
+ debug("clustnum: %d, startsect: %d\n", clustnum, startsect);
+
+ if (disk_write(startsect, size / mydata->sect_size, buffer) < 0) {
+ debug("Error writing data\n");
+ return -1;
+ }
+
+ if (size % mydata->sect_size) {
+ __u8 tmpbuf[mydata->sect_size];
+
+ idx = size / mydata->sect_size;
+ buffer += idx * mydata->sect_size;
+ memcpy(tmpbuf, buffer, size % mydata->sect_size);
+
+ if (disk_write(startsect + idx, 1, tmpbuf) < 0) {
+ debug("Error writing data\n");
+ return -1;
+ }
+
+ return 0;
+ }
+
+ 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_value(mydata, entry);
+ if (fat_val == 0)
+ break;
+ entry++;
+ }
+
+ return entry;
+}
+
+/*
+ * Write directory entries in 'get_dentfromdir_block' to block device
+ */
+static void flush_dir_table(fsdata *mydata, dir_entry **dentptr)
+{
+ int dir_newclust = 0;
+
+ if (set_cluster(mydata, dir_curclust,
+ get_dentfromdir_block,
+ mydata->clust_size * mydata->sect_size) != 0) {
+ printf("error: wrinting directory entry\n");
+ return;
+ }
+ dir_newclust = find_empty_cluster(mydata);
+ set_fatent_value(mydata, dir_curclust, 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);
+
+ dir_curclust = dir_newclust;
+
+ if (flush_fat_buffer(mydata) < 0)
+ return;
+
+ memset(get_dentfromdir_block, 0x00,
+ mydata->clust_size * mydata->sect_size);
+
+ *dentptr = (dir_entry *) get_dentfromdir_block;
+}
+
+/*
+ * Set empty cluster from 'entry' to the end of a file
+ */
+static int clear_fatent(fsdata *mydata, __u32 entry)
+{
+ __u32 fat_val;
+
+ while (1) {
+ fat_val = get_fatent_value(mydata, entry);
+ if (fat_val != 0)
+ set_fatent_value(mydata, entry, 0);
+ else
+ break;
+
+ if (fat_val == 0xfffffff || fat_val == 0xffff)
+ break;
+
+ entry = fat_val;
+ }
+
+ /* Flush fat buffer */
+ if (flush_fat_buffer(mydata) < 0)
+ return -1;
+
+ return 0;
+}
+
+/*
+ * Write at most 'maxsize' bytes from 'buffer' into
+ * the file associated with 'dentptr'
+ * Return the number of bytes read or -1 on fatal errors.
+ */
+static int
+set_contents(fsdata *mydata, dir_entry *dentptr, __u8 *buffer,
+ unsigned long maxsize)
+{
+ unsigned long filesize = FAT2CPU32(dentptr->size), gotsize = 0;
+ unsigned int bytesperclust = mydata->clust_size * mydata->sect_size;
+ __u32 curclust = START(dentptr);
+ __u32 endclust = 0, newclust = 0;
+ unsigned long actsize;
+
+ debug("Filesize: %ld bytes\n", filesize);
+
+ if (maxsize > 0 && filesize > maxsize)
+ filesize = maxsize;
+
+ debug("%ld bytes\n", filesize);
+
+ actsize = bytesperclust;
+ endclust = curclust;
+ do {
+ /* search for consecutive clusters */
+ while (actsize < filesize) {
+ newclust = determine_fatent(mydata, endclust);
+
+ if ((newclust - 1) != endclust)
+ goto getit;
+
+ if (CHECK_CLUST(newclust, mydata->fatsize)) {
+ debug("curclust: 0x%x\n", newclust);
+ debug("Invalid FAT entry\n");
+ return gotsize;
+ }
+ endclust = newclust;
+ actsize += bytesperclust;
+ }
+ /* actsize >= file size */
+ actsize -= bytesperclust;
+ /* set remaining clusters */
+ if (set_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
+ debug("error: writing cluster\n");
+ return -1;
+ }
+
+ /* set remaining bytes */
+ gotsize += (int)actsize;
+ filesize -= actsize;
+ buffer += actsize;
+ actsize = filesize;
+
+ if (set_cluster(mydata, endclust, buffer, (int)actsize) != 0) {
+ debug("error: writing cluster\n");
+ return -1;
+ }
+ gotsize += actsize;
+
+ /* Mark end of file in FAT */
+ if (mydata->fatsize == 16)
+ newclust = 0xffff;
+ else if (mydata->fatsize == 32)
+ newclust = 0xfffffff;
+ set_fatent_value(mydata, endclust, newclust);
+
+ return gotsize;
+getit:
+ if (set_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
+ debug("error: writing cluster\n");
+ return -1;
+ }
+ gotsize += (int)actsize;
+ filesize -= actsize;
+ buffer += actsize;
+
+ if (CHECK_CLUST(curclust, mydata->fatsize)) {
+ debug("curclust: 0x%x\n", curclust);
+ debug("Invalid FAT entry\n");
+ return gotsize;
+ }
+ actsize = bytesperclust;
+ curclust = endclust = newclust;
+ } while (1);
+}
+
+/*
+ * Fill dir_entry
+ */
+static void fill_dentry(fsdata *mydata, dir_entry *dentptr,
+ const char *filename, __u32 start_cluster, __u32 size, __u8 attr)
+{
+ if (mydata->fatsize == 32)
+ dentptr->starthi =
+ cpu_to_le16((start_cluster & 0xffff0000) >> 16);
+ dentptr->start = cpu_to_le16(start_cluster & 0xffff);
+ dentptr->size = cpu_to_le32(size);
+
+ dentptr->attr = attr;
+
+ set_name(dentptr, filename);
+}
+
+/*
+ * 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, unsigned long size)
+{
+ __u32 startsect, sect_num;
+
+ if (clustnum > 0) {
+ startsect = mydata->data_begin +
+ clustnum * mydata->clust_size;
+ } else {
+ startsect = mydata->rootdir_sect;
+ }
+
+ sect_num = size / mydata->sect_size;
+ if (size % mydata->sect_size)
+ sect_num++;
+
+ if (startsect + sect_num > total_sector)
+ return -1;
+
+ return 0;
+}
+
+/*
+ * Check if adding several entries exceed one cluster boundary
+ */
+static int is_next_clust(fsdata *mydata, dir_entry *dentptr)
+{
+ int cur_position;
+
+ cur_position = (__u8 *)dentptr - get_dentfromdir_block;
+
+ if (cur_position >= mydata->clust_size * mydata->sect_size)
+ return 1;
+ else
+ return 0;
+}
+
+static dir_entry *empty_dentptr;
+/*
+ * 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(fsdata *mydata, int startsect,
+ char *filename, dir_entry *retdent, __u32 start)
+{
+ __u16 prevcksum = 0xffff;
+ __u32 curclust = (startsect - mydata->data_begin) / mydata->clust_size;
+
+ debug("get_dentfromdir: %s\n", filename);
+
+ while (1) {
+ dir_entry *dentptr;
+
+ int i;
+
+ if (get_cluster(mydata, curclust, get_dentfromdir_block,
+ mydata->clust_size * mydata->sect_size) != 0) {
+ printf("Error: reading directory block\n");
+ return NULL;
+ }
+
+ dentptr = (dir_entry *)get_dentfromdir_block;
+
+ dir_curclust = curclust;
+
+ for (i = 0; i < DIRENTSPERCLUST; i++) {
+ char s_name[14], l_name[VFAT_MAXLEN_BYTES];
+
+ l_name[0] = '\0';
+ if (dentptr->name[0] == DELETED_FLAG) {
+ dentptr++;
+ if (is_next_clust(mydata, dentptr))
+ break;
+ continue;
+ }
+ if ((dentptr->attr & ATTR_VOLUME)) {
+#ifdef CONFIG_SUPPORT_VFAT
+ if ((dentptr->attr & ATTR_VFAT) &&
+ (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) {
+ prevcksum =
+ ((dir_slot *)dentptr)->alias_checksum;
+ get_long_file_name(mydata, curclust,
+ get_dentfromdir_block,
+ &dentptr, l_name);
+ debug("vfatname: |%s|\n", l_name);
+ } else
+#endif
+ {
+ /* Volume label or VFAT entry */
+ dentptr++;
+ if (is_next_clust(mydata, dentptr))
+ break;
+ continue;
+ }
+ }
+ if (dentptr->name[0] == 0) {
+ debug("Dentname == NULL - %d\n", i);
+ empty_dentptr = dentptr;
+ return NULL;
+ }
+
+ get_name(dentptr, s_name);
+
+ if (strcmp(filename, s_name)
+ && strcmp(filename, l_name)) {
+ debug("Mismatch: |%s|%s|\n",
+ s_name, l_name);
+ dentptr++;
+ if (is_next_clust(mydata, dentptr))
+ break;
+ continue;
+ }
+
+ memcpy(retdent, dentptr, sizeof(dir_entry));
+
+ debug("DentName: %s", s_name);
+ debug(", start: 0x%x", START(dentptr));
+ debug(", size: 0x%x %s\n",
+ FAT2CPU32(dentptr->size),
+ (dentptr->attr & ATTR_DIR) ?
+ "(DIR)" : "");
+
+ return dentptr;
+ }
+
+ curclust = get_fatent_value(mydata, dir_curclust);
+ if ((curclust >= 0xffffff8) || (curclust >= 0xfff8)) {
+ empty_dentptr = dentptr;
+ return NULL;
+ }
+ if (CHECK_CLUST(curclust, mydata->fatsize)) {
+ debug("curclust: 0x%x\n", curclust);
+ debug("Invalid FAT entry\n");
+ return NULL;
+ }
+ }
+
+ return NULL;
+}
+
+static int do_fat_write(const char *filename, void *buffer,
+ unsigned long size)
+{
+ dir_entry *dentptr, *retdent;
+ dir_slot *slotptr;
+ __u32 startsect;
+ __u32 start_cluster;
+ boot_sector bs;
+ volume_info volinfo;
+ fsdata datablock;
+ fsdata *mydata = &datablock;
+ int cursect;
+ int root_cluster, ret = -1, name_len;
+ char l_filename[VFAT_MAXLEN_BYTES];
+
+ dir_curclust = 0;
+
+ if (read_bootsectandvi(&bs, &volinfo, &mydata->fatsize)) {
+ debug("error: reading boot sector\n");
+ return -1;
+ }
+
+ total_sector = bs.total_sect;
+ if (total_sector == 0)
+ total_sector = part_size;
+
+ root_cluster = bs.root_cluster;
+
+ if (mydata->fatsize == 32)
+ mydata->fatlength = bs.fat32_length;
+ else
+ mydata->fatlength = bs.fat_length;
+
+ mydata->fat_sect = bs.reserved;
+
+ cursect = mydata->rootdir_sect
+ = mydata->fat_sect + mydata->fatlength * bs.fats;
+
+ mydata->sect_size = (bs.sector_size[1] << 8) + bs.sector_size[0];
+ mydata->clust_size = bs.cluster_size;
+
+ if (mydata->fatsize == 32) {
+ mydata->data_begin = mydata->rootdir_sect -
+ (mydata->clust_size * 2);
+ } else {
+ int rootdir_size;
+
+ rootdir_size = ((bs.dir_entries[1] * (int)256 +
+ bs.dir_entries[0]) *
+ sizeof(dir_entry)) /
+ mydata->sect_size;
+ mydata->data_begin = mydata->rootdir_sect +
+ rootdir_size -
+ (mydata->clust_size * 2);
+ }
+
+ mydata->fatbufnum = -1;
+ mydata->fatbuf = malloc(FATBUFSIZE);
+ if (mydata->fatbuf == NULL) {
+ debug("Error: allocating memory\n");
+ return -1;
+ }
+
+ if (disk_read(cursect,
+ (mydata->fatsize == 32) ?
+ (mydata->clust_size) :
+ PREFETCH_BLOCKS, do_fat_read_block) < 0) {
+ debug("Error: reading rootdir block\n");
+ goto exit;
+ }
+ dentptr = (dir_entry *) do_fat_read_block;
+
+ name_len = strlen(filename);
+ memcpy(l_filename, filename, name_len);
+ downcase(l_filename);
+
+ startsect = mydata->rootdir_sect;
+ retdent = find_directory_entry(mydata, startsect,
+ l_filename, dentptr, 0);
+ if (retdent) {
+ /* Update file size and start_cluster in a directory entry */
+ retdent->size = cpu_to_le32(size);
+ start_cluster = FAT2CPU16(retdent->start);
+ if (mydata->fatsize == 32)
+ start_cluster |=
+ (FAT2CPU16(retdent->starthi) << 16);
+
+ ret = check_overflow(mydata, start_cluster, size);
+ if (ret) {
+ printf("Error: %ld overflow\n", size);
+ goto exit;
+ }
+
+ ret = clear_fatent(mydata, start_cluster);
+ if (ret) {
+ printf("Error: clearing FAT entries\n");
+ goto exit;
+ }
+
+ ret = set_contents(mydata, retdent, buffer, size);
+ if (ret) {
+ printf("Error: writing contents\n");
+ goto exit;
+ }
+
+ /* Flush fat buffer */
+ ret = flush_fat_buffer(mydata);
+ if (ret) {
+ printf("Error: flush fat buffer\n");
+ goto exit;
+ }
+
+ /* Write directory table to device */
+ ret = set_cluster(mydata, dir_curclust,
+ get_dentfromdir_block,
+ mydata->clust_size * mydata->sect_size);
+ if (ret) {
+ printf("Error: wrinting directory entry\n");
+ goto exit;
+ }
+ } else {
+ slotptr = (dir_slot *)empty_dentptr;
+
+ /* Set short name to set alias checksum field in dir_slot */
+ set_name(empty_dentptr, filename);
+ fill_dir_slot(mydata, &empty_dentptr, filename);
+
+ ret = start_cluster = find_empty_cluster(mydata);
+ if (ret < 0) {
+ printf("Error: finding empty cluster\n");
+ goto exit;
+ }
+
+ ret = check_overflow(mydata, start_cluster, size);
+ if (ret) {
+ printf("Error: %ld overflow\n", size);
+ goto exit;
+ }
+
+ /* Set attribute as archieve for regular file */
+ fill_dentry(mydata, empty_dentptr, filename,
+ start_cluster, size, 0x20);
+
+ ret = set_contents(mydata, empty_dentptr, buffer, size);
+ if (ret) {
+ printf("Error: writing contents\n");
+ goto exit;
+ }
+
+ /* Flush fat buffer */
+ ret = flush_fat_buffer(mydata);
+ if (ret) {
+ printf("Error: flush fat buffer\n");
+ goto exit;
+ }
+
+ /* Write directory table to device */
+ ret = set_cluster(mydata, dir_curclust,
+ get_dentfromdir_block,
+ mydata->clust_size * mydata->sect_size);
+ if (ret) {
+ printf("Error: writing directory entry\n");
+ goto exit;
+ }
+ }
+
+exit:
+ free(mydata->fatbuf);
+ return ret;
+}
+
+int file_fat_write(const char *filename, void *buffer, unsigned long maxsize)
+{
+ printf("writing %s\n", filename);
+ return do_fat_write(filename, buffer, maxsize);
+}
OpenPOWER on IntegriCloud