]> git.kernelconcepts.de Git - karo-tx-uboot.git/blobdiff - fs/fat/fat.c
FAT: remove cur_part_nr
[karo-tx-uboot.git] / fs / fat / fat.c
index a9dde7defe8ff544b197631fa1f24ad435116f19..731d3690c318d523aa216a4b0e4785e062886730 100644 (file)
 
 #include <common.h>
 #include <config.h>
+#include <exports.h>
 #include <fat.h>
 #include <asm/byteorder.h>
 #include <part.h>
+#include <malloc.h>
+#include <linux/compiler.h>
 
 /*
  * Convert a string to lowercase.
  */
-static void
-downcase(char *str)
+static void downcase(char *str)
 {
        while (*str != '\0') {
                TOLOWER(*str);
@@ -43,83 +45,77 @@ downcase(char *str)
        }
 }
 
-static  block_dev_desc_t *cur_dev = NULL;
-static unsigned long part_offset = 0;
-static int cur_part = 1;
+static block_dev_desc_t *cur_dev;
+static disk_partition_t cur_part_info;
 
-#define DOS_PART_TBL_OFFSET    0x1be
-#define DOS_PART_MAGIC_OFFSET  0x1fe
+#define DOS_BOOT_MAGIC_OFFSET  0x1fe
 #define DOS_FS_TYPE_OFFSET     0x36
+#define DOS_FS32_TYPE_OFFSET   0x52
 
-int disk_read (__u32 startblock, __u32 getsize, __u8 * bufptr)
+static int disk_read(__u32 block, __u32 nr_blocks, void *buf)
 {
-       startblock += part_offset;
-       if (cur_dev == NULL)
+       if (!cur_dev || !cur_dev->block_read)
                return -1;
-       if (cur_dev->block_read) {
-               return cur_dev->block_read (cur_dev->dev
-                       , startblock, getsize, (unsigned long *)bufptr);
-       }
-       return -1;
-}
 
+       return cur_dev->block_read(cur_dev->dev,
+                       cur_part_info.start + block, nr_blocks, buf);
+}
 
-int
-fat_register_device(block_dev_desc_t *dev_desc, int part_no)
+int fat_register_device(block_dev_desc_t * dev_desc, int part_no)
 {
-       unsigned char buffer[SECTOR_SIZE];
-       disk_partition_t info;
+       ALLOC_CACHE_ALIGN_BUFFER(unsigned char, buffer, dev_desc->blksz);
+
+       /* First close any currently found FAT filesystem */
+       cur_dev = NULL;
 
-       if (!dev_desc->block_read)
-               return -1;
-       cur_dev = dev_desc;
-       /* check if we have a MBR (on floppies we have only a PBR) */
-       if (dev_desc->block_read (dev_desc->dev, 0, 1, (ulong *) buffer) != 1) {
-               printf ("** Can't read from device %d **\n", dev_desc->dev);
-               return -1;
-       }
-       if (buffer[DOS_PART_MAGIC_OFFSET] != 0x55 ||
-               buffer[DOS_PART_MAGIC_OFFSET + 1] != 0xaa) {
-               /* no signature found */
-               return -1;
-       }
 #if (defined(CONFIG_CMD_IDE) || \
      defined(CONFIG_CMD_SATA) || \
      defined(CONFIG_CMD_SCSI) || \
      defined(CONFIG_CMD_USB) || \
      defined(CONFIG_MMC) || \
      defined(CONFIG_SYSTEMACE) )
-       /* First we assume, there is a MBR */
-       if (!get_partition_info (dev_desc, part_no, &info)) {
-               part_offset = info.start;
-               cur_part = part_no;
-       } else if (!strncmp((char *)&buffer[DOS_FS_TYPE_OFFSET], "FAT", 3)) {
-               /* ok, we assume we are on a PBR only */
-               cur_part = 1;
-               part_offset = 0;
-       } else {
-               printf ("** Partition %d not valid on device %d **\n",
-                               part_no, dev_desc->dev);
+
+       /* Read the partition table, if present */
+       if (!get_partition_info(dev_desc, part_no, &cur_part_info))
+               cur_dev = dev_desc;
+#endif
+
+       /* Otherwise it might be a superfloppy (whole-disk FAT filesystem) */
+       if (!cur_dev) {
+               if (part_no != 0) {
+                       printf("** Partition %d not valid on device %d **\n",
+                                       part_no, dev_desc->dev);
+                       return -1;
+               }
+
+               cur_dev = dev_desc;
+               cur_part_info.start = 0;
+               cur_part_info.size = dev_desc->lba;
+               cur_part_info.blksz = dev_desc->blksz;
+               memset(cur_part_info.name, 0, sizeof(cur_part_info.name));
+               memset(cur_part_info.type, 0, sizeof(cur_part_info.type));
+       }
+
+       /* Make sure it has a valid FAT header */
+       if (disk_read(0, 1, buffer) != 1) {
+               cur_dev = NULL;
                return -1;
        }
 
-#else
-       if (!strncmp((char *)&buffer[DOS_FS_TYPE_OFFSET],"FAT",3)) {
-               /* ok, we assume we are on a PBR only */
-               cur_part = 1;
-               part_offset = 0;
-               info.start = part_offset;
-       } else {
-               /* FIXME we need to determine the start block of the
-                * partition where the DOS FS resides. This can be done
-                * by using the get_partition_info routine. For this
-                * purpose the libpart must be included.
-                */
-               part_offset = 32;
-               cur_part = 1;
+       /* Check if it's actually a DOS volume */
+       if (memcmp(buffer + DOS_BOOT_MAGIC_OFFSET, "\x55\xAA", 2)) {
+               cur_dev = NULL;
+               return -1;
        }
-#endif
-       return 0;
+
+       /* Check for FAT12/FAT16/FAT32 filesystem */
+       if (!memcmp(buffer + DOS_FS_TYPE_OFFSET, "FAT", 3))
+               return 0;
+       if (!memcmp(buffer + DOS_FS32_TYPE_OFFSET, "FAT32", 5))
+               return 0;
+
+       cur_dev = NULL;
+       return -1;
 }
 
 
@@ -127,48 +123,26 @@ fat_register_device(block_dev_desc_t *dev_desc, int part_no)
  * Get the first occurence of a directory delimiter ('/' or '\') in a string.
  * Return index into string if found, -1 otherwise.
  */
-static int
-dirdelim(char *str)
+static int dirdelim(char *str)
 {
        char *start = str;
 
        while (*str != '\0') {
-               if (ISDIRDELIM(*str)) return str - start;
+               if (ISDIRDELIM(*str))
+                       return str - start;
                str++;
        }
        return -1;
 }
 
-
-/*
- * Match volume_info fs_type strings.
- * Return 0 on match, -1 otherwise.
- */
-static int
-compare_sign(char *str1, char *str2)
-{
-       char *end = str1+SIGNLEN;
-
-       while (str1 != end) {
-               if (*str1 != *str2) {
-                       return -1;
-               }
-               str1++;
-               str2++;
-       }
-
-       return 0;
-}
-
-
 /*
  * Extract zero terminated short name from a directory entry.
  */
-static void get_name (dir_entry *dirent, char *s_name)
+static void get_name(dir_entry *dirent, char *s_name)
 {
        char *ptr;
 
-       memcpy (s_name, dirent->name, 8);
+       memcpy(s_name, dirent->name, 8);
        s_name[8] = '\0';
        ptr = s_name;
        while (*ptr && *ptr != ' ')
@@ -176,7 +150,7 @@ static void get_name (dir_entry *dirent, char *s_name)
        if (dirent->ext[0] && dirent->ext[0] != ' ') {
                *ptr = '.';
                ptr++;
-               memcpy (ptr, dirent->ext, 3);
+               memcpy(ptr, dirent->ext, 3);
                ptr[3] = '\0';
                while (*ptr && *ptr != ' ')
                        ptr++;
@@ -186,19 +160,19 @@ static void get_name (dir_entry *dirent, char *s_name)
                *s_name = '\0';
        else if (*s_name == aRING)
                *s_name = DELETED_FLAG;
-       downcase (s_name);
+       downcase(s_name);
 }
 
 /*
  * Get the entry at index 'entry' in a FAT (12/16/32) table.
  * On failure 0x00 is returned.
  */
-static __u32
-get_fatent(fsdata *mydata, __u32 entry)
+static __u32 get_fatent(fsdata *mydata, __u32 entry)
 {
        __u32 bufnum;
-       __u32 offset;
+       __u32 off16, offset;
        __u32 ret = 0x00;
+       __u16 val1, val2;
 
        switch (mydata->fatsize) {
        case 32:
@@ -219,19 +193,23 @@ get_fatent(fsdata *mydata, __u32 entry)
                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 = FATBUFSIZE/FS_BLOCK_SIZE;
+               __u32 getsize = FATBUFBLOCKS;
                __u8 *bufptr = mydata->fatbuf;
                __u32 fatlength = mydata->fatlength;
                __u32 startblock = bufnum * FATBUFBLOCKS;
 
-               fatlength *= SECTOR_SIZE;       /* We want it in bytes now */
+               if (startblock + getsize > fatlength)
+                       getsize = fatlength - startblock;
+
                startblock += mydata->fat_sect; /* Offset from start of disk */
 
-               if (getsize > fatlength) getsize = fatlength;
                if (disk_read(startblock, getsize, bufptr) < 0) {
-                       FAT_DPRINT("Error reading FAT blocks\n");
+                       debug("Error reading FAT blocks\n");
                        return ret;
                }
                mydata->fatbufnum = bufnum;
@@ -240,50 +218,48 @@ get_fatent(fsdata *mydata, __u32 entry)
        /* Get the actual entry from the table */
        switch (mydata->fatsize) {
        case 32:
-               ret = FAT2CPU32(((__u32*)mydata->fatbuf)[offset]);
+               ret = FAT2CPU32(((__u32 *) mydata->fatbuf)[offset]);
                break;
        case 16:
-               ret = FAT2CPU16(((__u16*)mydata->fatbuf)[offset]);
+               ret = FAT2CPU16(((__u16 *) mydata->fatbuf)[offset]);
                break;
-       case 12: {
-               __u32 off16 = (offset*3)/4;
-               __u16 val1, val2;
+       case 12:
+               off16 = (offset * 3) / 4;
 
                switch (offset & 0x3) {
                case 0:
-                       ret = FAT2CPU16(((__u16*)mydata->fatbuf)[off16]);
+                       ret = FAT2CPU16(((__u16 *) mydata->fatbuf)[off16]);
                        ret &= 0xfff;
                        break;
                case 1:
-                       val1 = FAT2CPU16(((__u16*)mydata->fatbuf)[off16]);
+                       val1 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
                        val1 &= 0xf000;
-                       val2 = FAT2CPU16(((__u16*)mydata->fatbuf)[off16+1]);
+                       val2 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]);
                        val2 &= 0x00ff;
                        ret = (val2 << 4) | (val1 >> 12);
                        break;
                case 2:
-                       val1 = FAT2CPU16(((__u16*)mydata->fatbuf)[off16]);
+                       val1 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
                        val1 &= 0xff00;
-                       val2 = FAT2CPU16(((__u16*)mydata->fatbuf)[off16+1]);
+                       val2 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]);
                        val2 &= 0x000f;
                        ret = (val2 << 8) | (val1 >> 8);
                        break;
                case 3:
-                       ret = FAT2CPU16(((__u16*)mydata->fatbuf)[off16]);;
+                       ret = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
                        ret = (ret & 0xfff0) >> 4;
                        break;
                default:
                        break;
                }
+               break;
        }
-       break;
-       }
-       FAT_DPRINT("ret: %d, offset: %d\n", ret, offset);
+       debug("FAT%d: ret: %08x, offset: %04x\n",
+              mydata->fatsize, ret, offset);
 
        return ret;
 }
 
-
 /*
  * Read at most 'size' bytes from the specified cluster into 'buffer'.
  * Return 0 on success, -1 otherwise.
@@ -291,206 +267,293 @@ get_fatent(fsdata *mydata, __u32 entry)
 static int
 get_cluster(fsdata *mydata, __u32 clustnum, __u8 *buffer, unsigned long size)
 {
-       int idx = 0;
+       __u32 idx = 0;
        __u32 startsect;
+       int ret;
 
        if (clustnum > 0) {
-               startsect = mydata->data_begin + clustnum*mydata->clust_size;
+               startsect = mydata->data_begin +
+                               clustnum * mydata->clust_size;
        } else {
                startsect = mydata->rootdir_sect;
        }
 
-       FAT_DPRINT("gc - clustnum: %d, startsect: %d\n", clustnum, startsect);
-       if (disk_read(startsect, size/FS_BLOCK_SIZE , buffer) < 0) {
-               FAT_DPRINT("Error reading data\n");
-               return -1;
+       debug("gc - clustnum: %d, startsect: %d\n", clustnum, startsect);
+
+       if ((unsigned long)buffer & (ARCH_DMA_MINALIGN - 1)) {
+               ALLOC_CACHE_ALIGN_BUFFER(__u8, tmpbuf, mydata->sect_size);
+
+               printf("FAT: Misaligned buffer address (%p)\n", buffer);
+
+               while (size >= mydata->sect_size) {
+                       ret = disk_read(startsect++, 1, tmpbuf);
+                       if (ret != 1) {
+                               debug("Error reading data (got %d)\n", ret);
+                               return -1;
+                       }
+
+                       memcpy(buffer, tmpbuf, mydata->sect_size);
+                       buffer += mydata->sect_size;
+                       size -= mydata->sect_size;
+               }
+       } else {
+               idx = size / mydata->sect_size;
+               ret = disk_read(startsect, idx, buffer);
+               if (ret != idx) {
+                       debug("Error reading data (got %d)\n", ret);
+                       return -1;
+               }
+               startsect += idx;
+               idx *= mydata->sect_size;
+               buffer += idx;
+               size -= idx;
        }
-       if(size % FS_BLOCK_SIZE) {
-               __u8 tmpbuf[FS_BLOCK_SIZE];
-               idx= size/FS_BLOCK_SIZE;
-               if (disk_read(startsect + idx, 1, tmpbuf) < 0) {
-                       FAT_DPRINT("Error reading data\n");
+       if (size) {
+               ALLOC_CACHE_ALIGN_BUFFER(__u8, tmpbuf, mydata->sect_size);
+
+               ret = disk_read(startsect, 1, tmpbuf);
+               if (ret != 1) {
+                       debug("Error reading data (got %d)\n", ret);
                        return -1;
                }
-               buffer += idx*FS_BLOCK_SIZE;
 
-               memcpy(buffer, tmpbuf, size % FS_BLOCK_SIZE);
-               return 0;
+               memcpy(buffer, tmpbuf, size);
        }
 
        return 0;
 }
 
-
 /*
- * Read at most 'maxsize' bytes from the file associated with 'dentptr'
+ * Read at most 'maxsize' bytes from 'pos' in the file associated with 'dentptr'
  * into 'buffer'.
  * Return the number of bytes read or -1 on fatal errors.
  */
+__u8 get_contents_vfatname_block[MAX_CLUSTSIZE]
+       __aligned(ARCH_DMA_MINALIGN);
+
 static long
-get_contents(fsdata *mydata, dir_entry *dentptr, __u8 *buffer,
-            unsigned long maxsize)
+get_contents(fsdata *mydata, dir_entry *dentptr, unsigned long pos,
+            __u8 *buffer, unsigned long maxsize)
 {
        unsigned long filesize = FAT2CPU32(dentptr->size), gotsize = 0;
-       unsigned int bytesperclust = mydata->clust_size * SECTOR_SIZE;
+       unsigned int bytesperclust = mydata->clust_size * mydata->sect_size;
        __u32 curclust = START(dentptr);
        __u32 endclust, newclust;
        unsigned long actsize;
 
-       FAT_DPRINT("Filesize: %ld bytes\n", filesize);
+       debug("Filesize: %ld bytes\n", filesize);
+
+       if (pos >= filesize) {
+               debug("Read position past EOF: %lu\n", pos);
+               return gotsize;
+       }
+
+       if (maxsize > 0 && filesize > pos + maxsize)
+               filesize = pos + maxsize;
+
+       debug("%ld bytes\n", filesize);
 
-       if (maxsize > 0 && filesize > maxsize) filesize = maxsize;
+       actsize = bytesperclust;
 
-       FAT_DPRINT("Reading: %ld bytes\n", filesize);
+       /* go to cluster at pos */
+       while (actsize <= pos) {
+               curclust = get_fatent(mydata, curclust);
+               if (CHECK_CLUST(curclust, mydata->fatsize)) {
+                       debug("curclust: 0x%x\n", curclust);
+                       debug("Invalid FAT entry\n");
+                       return gotsize;
+               }
+               actsize += bytesperclust;
+       }
+
+       /* actsize > pos */
+       actsize -= bytesperclust;
+       filesize -= actsize;
+       pos -= actsize;
+
+       /* align to beginning of next cluster if any */
+       if (pos) {
+               actsize = min(filesize, bytesperclust);
+               if (get_cluster(mydata, curclust, get_contents_vfatname_block,
+                               (int)actsize) != 0) {
+                       printf("Error reading cluster\n");
+                       return -1;
+               }
+               filesize -= actsize;
+               actsize -= pos;
+               memcpy(buffer, get_contents_vfatname_block + pos, actsize);
+               gotsize += actsize;
+               if (!filesize)
+                       return gotsize;
+               buffer += actsize;
+
+               curclust = get_fatent(mydata, curclust);
+               if (CHECK_CLUST(curclust, mydata->fatsize)) {
+                       debug("curclust: 0x%x\n", curclust);
+                       debug("Invalid FAT entry\n");
+                       return gotsize;
+               }
+       }
+
+       actsize = bytesperclust;
+       endclust = curclust;
 
-       actsize=bytesperclust;
-       endclust=curclust;
        do {
                /* search for consecutive clusters */
-               while(actsize < filesize) {
+               while (actsize < filesize) {
                        newclust = get_fatent(mydata, endclust);
-                       if((newclust -1)!=endclust)
+                       if ((newclust - 1) != endclust)
                                goto getit;
                        if (CHECK_CLUST(newclust, mydata->fatsize)) {
-                               FAT_DPRINT("curclust: 0x%x\n", newclust);
-                               FAT_DPRINT("Invalid FAT entry\n");
+                               debug("curclust: 0x%x\n", newclust);
+                               debug("Invalid FAT entry\n");
                                return gotsize;
                        }
-                       endclust=newclust;
-                       actsize+= bytesperclust;
-               }
-               /* actsize >= file size */
-               actsize -= bytesperclust;
-               /* get remaining clusters */
-               if (get_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
-                       FAT_ERROR("Error reading cluster\n");
-                       return -1;
+                       endclust = newclust;
+                       actsize += bytesperclust;
                }
+
                /* get remaining bytes */
-               gotsize += (int)actsize;
-               filesize -= actsize;
-               buffer += actsize;
-               actsize= filesize;
-               if (get_cluster(mydata, endclust, buffer, (int)actsize) != 0) {
-                       FAT_ERROR("Error reading cluster\n");
+               actsize = filesize;
+               if (get_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
+                       printf("Error reading cluster\n");
                        return -1;
                }
-               gotsize+=actsize;
+               gotsize += actsize;
                return gotsize;
 getit:
                if (get_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
-                       FAT_ERROR("Error reading cluster\n");
+                       printf("Error reading cluster\n");
                        return -1;
                }
                gotsize += (int)actsize;
                filesize -= actsize;
                buffer += actsize;
+
                curclust = get_fatent(mydata, endclust);
                if (CHECK_CLUST(curclust, mydata->fatsize)) {
-                       FAT_DPRINT("curclust: 0x%x\n", curclust);
-                       FAT_ERROR("Invalid FAT entry\n");
+                       debug("curclust: 0x%x\n", curclust);
+                       printf("Invalid FAT entry\n");
                        return gotsize;
                }
-               actsize=bytesperclust;
-               endclust=curclust;
+               actsize = bytesperclust;
+               endclust = curclust;
        } while (1);
 }
 
-
 #ifdef CONFIG_SUPPORT_VFAT
 /*
  * Extract the file name information from 'slotptr' into 'l_name',
  * starting at l_name[*idx].
  * Return 1 if terminator (zero byte) is found, 0 otherwise.
  */
-static int
-slot2str(dir_slot *slotptr, char *l_name, int *idx)
+static int slot2str(dir_slot *slotptr, char *l_name, int *idx)
 {
        int j;
 
        for (j = 0; j <= 8; j += 2) {
                l_name[*idx] = slotptr->name0_4[j];
-               if (l_name[*idx] == 0x00) return 1;
+               if (l_name[*idx] == 0x00)
+                       return 1;
                (*idx)++;
        }
        for (j = 0; j <= 10; j += 2) {
                l_name[*idx] = slotptr->name5_10[j];
-               if (l_name[*idx] == 0x00) return 1;
+               if (l_name[*idx] == 0x00)
+                       return 1;
                (*idx)++;
        }
        for (j = 0; j <= 2; j += 2) {
                l_name[*idx] = slotptr->name11_12[j];
-               if (l_name[*idx] == 0x00) return 1;
+               if (l_name[*idx] == 0x00)
+                       return 1;
                (*idx)++;
        }
 
        return 0;
 }
 
-
 /*
  * 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'
  * Return 0 on success, -1 otherwise.
  */
-__u8    get_vfatname_block[MAX_CLUSTSIZE];
 static int
 get_vfatname(fsdata *mydata, int curclust, __u8 *cluster,
             dir_entry *retdent, char *l_name)
 {
        dir_entry *realdent;
-       dir_slot  *slotptr = (dir_slot*) retdent;
-       __u8      *nextclust = cluster + mydata->clust_size * SECTOR_SIZE;
-       __u8       counter = (slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff;
+       dir_slot *slotptr = (dir_slot *)retdent;
+       __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;
 
-       while ((__u8*)slotptr < nextclust) {
-               if (counter == 0) break;
+       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 >= nextclust) {
+       if ((__u8 *)slotptr >= buflimit) {
                dir_slot *slotptr2;
 
-               slotptr--;
+               if (curclust == 0)
+                       return -1;
                curclust = get_fatent(mydata, curclust);
                if (CHECK_CLUST(curclust, mydata->fatsize)) {
-                       FAT_DPRINT("curclust: 0x%x\n", curclust);
-                       FAT_ERROR("Invalid FAT entry\n");
+                       debug("curclust: 0x%x\n", curclust);
+                       printf("Invalid FAT entry\n");
                        return -1;
                }
-               if (get_cluster(mydata, curclust, get_vfatname_block,
-                               mydata->clust_size * SECTOR_SIZE) != 0) {
-                       FAT_DPRINT("Error: reading directory block\n");
+
+               if (get_cluster(mydata, curclust, get_contents_vfatname_block,
+                               mydata->clust_size * mydata->sect_size) != 0) {
+                       debug("Error: reading directory block\n");
                        return -1;
                }
-               slotptr2 = (dir_slot*) get_vfatname_block;
-               while (slotptr2->id > 0x01) {
+
+               slotptr2 = (dir_slot *)get_contents_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 + 1;
-               while ((__u8*)slotptr2 >= get_vfatname_block) {
-                       slot2str(slotptr2, l_name, &idx);
+               realdent = (dir_entry *)slotptr2;
+               while ((__u8 *)slotptr2 > get_contents_vfatname_block) {
                        slotptr2--;
+                       slot2str(slotptr2, l_name, &idx);
                }
        } else {
                /* Save the real directory entry */
-               realdent = (dir_entry*)slotptr;
+               realdent = (dir_entry *)slotptr;
        }
 
        do {
                slotptr--;
-               if (slot2str(slotptr, l_name, &idx)) break;
+               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;
+       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 */
@@ -499,529 +562,697 @@ get_vfatname(fsdata *mydata, int curclust, __u8 *cluster,
        return 0;
 }
 
-
 /* Calculate short name checksum */
-static __u8
-mkcksum(const char *str)
+static __u8 mkcksum(const char name[8], const char ext[3])
 {
        int i;
+
        __u8 ret = 0;
 
-       for (i = 0; i < 11; i++) {
-               ret = (((ret&1)<<7)|((ret&0xfe)>>1)) + str[i];
-       }
+       for (i = 0; i < sizeof(name); i++)
+               ret = (((ret & 1) << 7) | ((ret & 0xfe) >> 1)) + name[i];
+       for (i = 0; i < sizeof(ext); i++)
+               ret = (((ret & 1) << 7) | ((ret & 0xfe) >> 1)) + ext[i];
 
        return ret;
 }
-#endif
-
+#endif /* CONFIG_SUPPORT_VFAT */
 
 /*
  * Get the directory entry associated with 'filename' from the directory
  * starting at 'startsect'
  */
-__u8 get_dentfromdir_block[MAX_CLUSTSIZE];
-static dir_entry *get_dentfromdir (fsdata * mydata, int startsect,
-                                  char *filename, dir_entry * retdent,
-                                  int dols)
+__u8 get_dentfromdir_block[MAX_CLUSTSIZE]
+       __aligned(ARCH_DMA_MINALIGN);
+
+static dir_entry *get_dentfromdir(fsdata *mydata, int startsect,
+                                 char *filename, dir_entry *retdent,
+                                 int dols)
 {
-    __u16 prevcksum = 0xffff;
-    __u32 curclust = START (retdent);
-    int files = 0, dirs = 0;
+       __u16 prevcksum = 0xffff;
+       __u32 curclust = START(retdent);
+       int files = 0, dirs = 0;
 
-    FAT_DPRINT ("get_dentfromdir: %s\n", filename);
-    while (1) {
-       dir_entry *dentptr;
-       int i;
+       debug("get_dentfromdir: %s\n", filename);
 
-       if (get_cluster (mydata, curclust, get_dentfromdir_block,
-                mydata->clust_size * SECTOR_SIZE) != 0) {
-           FAT_DPRINT ("Error: reading directory block\n");
-           return NULL;
-       }
-       dentptr = (dir_entry *) get_dentfromdir_block;
-       for (i = 0; i < DIRENTSPERCLUST; i++) {
-           char s_name[14], l_name[256];
-
-           l_name[0] = '\0';
-           if (dentptr->name[0] == DELETED_FLAG) {
-                   dentptr++;
-                   continue;
-           }
-           if ((dentptr->attr & ATTR_VOLUME)) {
+       while (1) {
+               dir_entry *dentptr;
+
+               int i;
+
+               if (get_cluster(mydata, curclust, get_dentfromdir_block,
+                               mydata->clust_size * mydata->sect_size) != 0) {
+                       debug("Error: reading directory block\n");
+                       return NULL;
+               }
+
+               dentptr = (dir_entry *)get_dentfromdir_block;
+
+               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++;
+                               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_vfatname (mydata, curclust, get_dentfromdir_block,
-                                 dentptr, l_name);
-                   if (dols) {
-                       int isdir = (dentptr->attr & ATTR_DIR);
-                       char dirc;
-                       int doit = 0;
-
-                       if (isdir) {
-                           dirs++;
-                           dirc = '/';
-                           doit = 1;
-                       } else {
-                           dirc = ' ';
-                           if (l_name[0] != 0) {
-                               files++;
-                               doit = 1;
-                           }
+                               if ((dentptr->attr & ATTR_VFAT) == ATTR_VFAT &&
+                                   (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) {
+                                       prevcksum = ((dir_slot *)dentptr)->alias_checksum;
+                                       get_vfatname(mydata, curclust,
+                                                    get_dentfromdir_block,
+                                                    dentptr, l_name);
+                                       if (dols) {
+                                               int isdir;
+                                               char dirc;
+                                               int doit = 0;
+
+                                               isdir = (dentptr->attr & ATTR_DIR);
+
+                                               if (isdir) {
+                                                       dirs++;
+                                                       dirc = '/';
+                                                       doit = 1;
+                                               } else {
+                                                       dirc = ' ';
+                                                       if (l_name[0] != 0) {
+                                                               files++;
+                                                               doit = 1;
+                                                       }
+                                               }
+                                               if (doit) {
+                                                       if (dirc == ' ') {
+                                                               printf(" %8ld   %s%c\n",
+                                                                       (long)FAT2CPU32(dentptr->size),
+                                                                       l_name,
+                                                                       dirc);
+                                                       } else {
+                                                               printf("            %s%c\n",
+                                                                       l_name,
+                                                                       dirc);
+                                                       }
+                                               }
+                                               dentptr++;
+                                               continue;
+                                       }
+                                       debug("vfatname: |%s|\n", l_name);
+                               } else
+#endif
+                               {
+                                       /* Volume label or VFAT entry */
+                                       dentptr++;
+                                       continue;
+                               }
                        }
-                       if (doit) {
-                           if (dirc == ' ') {
-                               printf (" %8ld   %s%c\n",
-                                       (long) FAT2CPU32 (dentptr->size),
-                                       l_name, dirc);
-                           } else {
-                               printf ("            %s%c\n", l_name, dirc);
-                           }
+                       if (dentptr->name[0] == 0) {
+                               if (dols) {
+                                       printf("\n%d file(s), %d dir(s)\n\n",
+                                               files, dirs);
+                               }
+                               debug("Dentname == NULL - %d\n", i);
+                               return NULL;
                        }
-                       dentptr++;
-                       continue;
-                   }
-                   FAT_DPRINT ("vfatname: |%s|\n", l_name);
-               } else
-#endif
-               {
-                   /* Volume label or VFAT entry */
-                   dentptr++;
-                   continue;
-               }
-           }
-           if (dentptr->name[0] == 0) {
-               if (dols) {
-                   printf ("\n%d file(s), %d dir(s)\n\n", files, dirs);
-               }
-               FAT_DPRINT ("Dentname == NULL - %d\n", i);
-               return NULL;
-           }
 #ifdef CONFIG_SUPPORT_VFAT
-           if (dols && mkcksum (dentptr->name) == prevcksum) {
-               dentptr++;
-               continue;
-           }
+                       __u8 csum = mkcksum(dentptr->name, dentptr->ext);
+                       if (dols && csum == prevcksum) {
+                               prevcksum = 0xffff;
+                               dentptr++;
+                               continue;
+                       }
 #endif
-           get_name (dentptr, s_name);
-           if (dols) {
-               int isdir = (dentptr->attr & ATTR_DIR);
-               char dirc;
-               int doit = 0;
-
-               if (isdir) {
-                   dirs++;
-                   dirc = '/';
-                   doit = 1;
-               } else {
-                   dirc = ' ';
-                   if (s_name[0] != 0) {
-                       files++;
-                       doit = 1;
-                   }
+                       get_name(dentptr, s_name);
+                       if (dols) {
+                               int isdir = (dentptr->attr & ATTR_DIR);
+                               char dirc;
+                               int doit = 0;
+
+                               if (isdir) {
+                                       dirs++;
+                                       dirc = '/';
+                                       doit = 1;
+                               } else {
+                                       dirc = ' ';
+                                       if (s_name[0] != 0) {
+                                               files++;
+                                               doit = 1;
+                                       }
+                               }
+
+                               if (doit) {
+                                       if (dirc == ' ') {
+                                               printf(" %8ld   %s%c\n",
+                                                       (long)FAT2CPU32(dentptr->size),
+                                                       s_name, dirc);
+                                       } else {
+                                               printf("            %s%c\n",
+                                                       s_name, dirc);
+                                       }
+                               }
+
+                               dentptr++;
+                               continue;
+                       }
+
+                       if (strcmp(filename, s_name)
+                           && strcmp(filename, l_name)) {
+                               debug("Mismatch: |%s|%s|\n", s_name, l_name);
+                               dentptr++;
+                               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 retdent;
                }
-               if (doit) {
-                   if (dirc == ' ') {
-                       printf (" %8ld   %s%c\n",
-                               (long) FAT2CPU32 (dentptr->size), s_name,
-                               dirc);
-                   } else {
-                       printf ("            %s%c\n", s_name, dirc);
-                   }
+
+               curclust = get_fatent(mydata, curclust);
+               if (CHECK_CLUST(curclust, mydata->fatsize)) {
+                       debug("curclust: 0x%x\n", curclust);
+                       printf("Invalid FAT entry\n");
+                       return NULL;
                }
-               dentptr++;
-               continue;
-           }
-           if (strcmp (filename, s_name) && strcmp (filename, l_name)) {
-               FAT_DPRINT ("Mismatch: |%s|%s|\n", s_name, l_name);
-               dentptr++;
-               continue;
-           }
-           memcpy (retdent, dentptr, sizeof (dir_entry));
-
-           FAT_DPRINT ("DentName: %s", s_name);
-           FAT_DPRINT (", start: 0x%x", START (dentptr));
-           FAT_DPRINT (", size:  0x%x %s\n",
-                       FAT2CPU32 (dentptr->size),
-                       (dentptr->attr & ATTR_DIR) ? "(DIR)" : "");
-
-           return retdent;
-       }
-       curclust = get_fatent (mydata, curclust);
-       if (CHECK_CLUST(curclust, mydata->fatsize)) {
-           FAT_DPRINT ("curclust: 0x%x\n", curclust);
-           FAT_ERROR ("Invalid FAT entry\n");
-           return NULL;
        }
-    }
 
-    return NULL;
+       return NULL;
 }
 
-
 /*
  * Read boot sector and volume info from a FAT filesystem
  */
 static int
 read_bootsectandvi(boot_sector *bs, volume_info *volinfo, int *fatsize)
 {
-       __u8 block[FS_BLOCK_SIZE];
+       __u8 *block;
        volume_info *vistart;
+       int ret = 0;
 
-       if (disk_read(0, 1, block) < 0) {
-               FAT_DPRINT("Error: reading block\n");
+       if (cur_dev == NULL) {
+               debug("Error: no device selected\n");
                return -1;
        }
 
+       block = memalign(ARCH_DMA_MINALIGN, cur_dev->blksz);
+       if (block == NULL) {
+               debug("Error: allocating block\n");
+               return -1;
+       }
+
+       if (disk_read(0, 1, block) < 0) {
+               debug("Error: reading block\n");
+               goto fail;
+       }
+
        memcpy(bs, block, sizeof(boot_sector));
-       bs->reserved    = FAT2CPU16(bs->reserved);
-       bs->fat_length  = FAT2CPU16(bs->fat_length);
-       bs->secs_track  = FAT2CPU16(bs->secs_track);
-       bs->heads       = FAT2CPU16(bs->heads);
-#if 0 /* UNUSED */
-       bs->hidden      = FAT2CPU32(bs->hidden);
-#endif
-       bs->total_sect  = FAT2CPU32(bs->total_sect);
+       bs->reserved = FAT2CPU16(bs->reserved);
+       bs->fat_length = FAT2CPU16(bs->fat_length);
+       bs->secs_track = FAT2CPU16(bs->secs_track);
+       bs->heads = FAT2CPU16(bs->heads);
+       bs->total_sect = FAT2CPU32(bs->total_sect);
 
        /* FAT32 entries */
        if (bs->fat_length == 0) {
                /* Assume FAT32 */
                bs->fat32_length = FAT2CPU32(bs->fat32_length);
-               bs->flags        = FAT2CPU16(bs->flags);
+               bs->flags = FAT2CPU16(bs->flags);
                bs->root_cluster = FAT2CPU32(bs->root_cluster);
-               bs->info_sector  = FAT2CPU16(bs->info_sector);
-               bs->backup_boot  = FAT2CPU16(bs->backup_boot);
-               vistart = (volume_info*) (block + sizeof(boot_sector));
+               bs->info_sector = FAT2CPU16(bs->info_sector);
+               bs->backup_boot = FAT2CPU16(bs->backup_boot);
+               vistart = (volume_info *)(block + sizeof(boot_sector));
                *fatsize = 32;
        } else {
-               vistart = (volume_info*) &(bs->fat32_length);
+               vistart = (volume_info *)&(bs->fat32_length);
                *fatsize = 0;
        }
        memcpy(volinfo, vistart, sizeof(volume_info));
 
-       /* Terminate fs_type string. Writing past the end of vistart
-          is ok - it's just the buffer. */
-       vistart->fs_type[8] = '\0';
-
        if (*fatsize == 32) {
-               if (compare_sign(FAT32_SIGN, vistart->fs_type) == 0) {
-                       return 0;
-               }
+               if (strncmp(FAT32_SIGN, vistart->fs_type, SIGNLEN) == 0)
+                       goto exit;
        } else {
-               if (compare_sign(FAT12_SIGN, vistart->fs_type) == 0) {
+               if (strncmp(FAT12_SIGN, vistart->fs_type, SIGNLEN) == 0) {
                        *fatsize = 12;
-                       return 0;
+                       goto exit;
                }
-               if (compare_sign(FAT16_SIGN, vistart->fs_type) == 0) {
+               if (strncmp(FAT16_SIGN, vistart->fs_type, SIGNLEN) == 0) {
                        *fatsize = 16;
-                       return 0;
+                       goto exit;
                }
        }
 
-       FAT_DPRINT("Error: broken fs_type sign\n");
-       return -1;
+       debug("Error: broken fs_type sign\n");
+fail:
+       ret = -1;
+exit:
+       free(block);
+       return ret;
 }
 
+__u8 do_fat_read_at_block[MAX_CLUSTSIZE]
+       __aligned(ARCH_DMA_MINALIGN);
 
-__u8 do_fat_read_block[MAX_CLUSTSIZE];  /* Block buffer */
 long
-do_fat_read (const char *filename, void *buffer, unsigned long maxsize,
-            int dols)
+do_fat_read_at(const char *filename, unsigned long pos, void *buffer,
+              unsigned long maxsize, int dols)
 {
-#if CONFIG_NIOS /* NIOS CPU cannot access big automatic arrays */
-    static
-#endif
-    char fnamecopy[2048];
-    boot_sector bs;
-    volume_info volinfo;
-    fsdata datablock;
-    fsdata *mydata = &datablock;
-    dir_entry *dentptr;
-    __u16 prevcksum = 0xffff;
-    char *subname = "";
-    int rootdir_size, cursect;
-    int idx, isdir = 0;
-    int files = 0, dirs = 0;
-    long ret = 0;
-    int firsttime;
-
-    if (read_bootsectandvi (&bs, &volinfo, &mydata->fatsize)) {
-       FAT_DPRINT ("Error: reading boot sector\n");
-       return -1;
-    }
-    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->clust_size = bs.cluster_size;
-    if (mydata->fatsize == 32) {
-       rootdir_size = mydata->clust_size;
-       mydata->data_begin = mydata->rootdir_sect   /* + rootdir_size */
-               - (mydata->clust_size * 2);
-    } else {
-       rootdir_size = ((bs.dir_entries[1] * (int) 256 + bs.dir_entries[0])
-                       * sizeof (dir_entry)) / SECTOR_SIZE;
-       mydata->data_begin = mydata->rootdir_sect + rootdir_size
-               - (mydata->clust_size * 2);
-    }
-    mydata->fatbufnum = -1;
-
-    FAT_DPRINT ("FAT%d, fatlength: %d\n", mydata->fatsize,
-               mydata->fatlength);
-    FAT_DPRINT ("Rootdir begins at sector: %d, offset: %x, size: %d\n"
-               "Data begins at: %d\n",
-               mydata->rootdir_sect, mydata->rootdir_sect * SECTOR_SIZE,
-               rootdir_size, mydata->data_begin);
-    FAT_DPRINT ("Cluster size: %d\n", mydata->clust_size);
-
-    /* "cwd" is always the root... */
-    while (ISDIRDELIM (*filename))
-       filename++;
-    /* Make a copy of the filename and convert it to lowercase */
-    strcpy (fnamecopy, filename);
-    downcase (fnamecopy);
-    if (*fnamecopy == '\0') {
-       if (!dols)
-           return -1;
-       dols = LS_ROOT;
-    } else if ((idx = dirdelim (fnamecopy)) >= 0) {
-       isdir = 1;
-       fnamecopy[idx] = '\0';
-       subname = fnamecopy + idx + 1;
-       /* Handle multiple delimiters */
-       while (ISDIRDELIM (*subname))
-           subname++;
-    } else if (dols) {
-       isdir = 1;
-    }
-
-    while (1) {
-       int i;
+       char fnamecopy[2048];
+       boot_sector bs;
+       volume_info volinfo;
+       fsdata datablock;
+       fsdata *mydata = &datablock;
+       dir_entry *dentptr = NULL;
+       __u16 prevcksum = 0xffff;
+       char *subname = "";
+       __u32 cursect;
+       int idx, isdir = 0;
+       int files = 0, dirs = 0;
+       long ret = -1;
+       int firsttime;
+       __u32 root_cluster = 0;
+       int rootdir_size = 0;
+       int j;
+
+       if (read_bootsectandvi(&bs, &volinfo, &mydata->fatsize)) {
+               debug("Error: reading boot sector\n");
+               return -1;
+       }
+
+       if (mydata->fatsize == 32) {
+               root_cluster = bs.root_cluster;
+               mydata->fatlength = bs.fat32_length;
+       } else {
+               mydata->fatlength = bs.fat_length;
+       }
 
-       if (disk_read (cursect, mydata->clust_size, do_fat_read_block) < 0) {
-           FAT_DPRINT ("Error: reading rootdir block\n");
-           return -1;
+       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->sect_size != cur_part_info.blksz) {
+               printf("Error: FAT sector size mismatch (fs=%hu, dev=%lu)\n",
+                               mydata->sect_size, cur_part_info.blksz);
+               return -1;
+       }
+
+       if (mydata->fatsize == 32) {
+               mydata->data_begin = mydata->rootdir_sect -
+                                       (mydata->clust_size * 2);
+       } else {
+               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 = memalign(ARCH_DMA_MINALIGN, FATBUFSIZE);
+       if (mydata->fatbuf == NULL) {
+               debug("Error: allocating memory\n");
+               return -1;
        }
-       dentptr = (dir_entry *) do_fat_read_block;
-       for (i = 0; i < DIRENTSPERBLOCK; i++) {
-           char s_name[14], l_name[256];
 
-           l_name[0] = '\0';
-           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_vfatname (mydata, 0, do_fat_read_block, dentptr, l_name);
-                   if (dols == LS_ROOT) {
-                       int isdir = (dentptr->attr & ATTR_DIR);
-                       char dirc;
-                       int doit = 0;
-
-                       if (isdir) {
-                           dirs++;
-                           dirc = '/';
-                           doit = 1;
-                       } else {
-                           dirc = ' ';
-                           if (l_name[0] != 0) {
-                               files++;
-                               doit = 1;
-                           }
+       debug("VFAT Support enabled\n");
+#endif
+       debug("FAT%d, fat_sect: %d, fatlength: %d\n",
+              mydata->fatsize, mydata->fat_sect, mydata->fatlength);
+       debug("Rootdir begins at cluster: %d, sector: %d, offset: %x\n"
+              "Data begins at: %d\n",
+              root_cluster,
+              mydata->rootdir_sect,
+              mydata->rootdir_sect * mydata->sect_size, mydata->data_begin);
+       debug("Sector size: %d, cluster size: %d\n", mydata->sect_size,
+             mydata->clust_size);
+
+       /* "cwd" is always the root... */
+       while (ISDIRDELIM(*filename))
+               filename++;
+
+       /* Make a copy of the filename and convert it to lowercase */
+       strcpy(fnamecopy, filename);
+       downcase(fnamecopy);
+
+       if (*fnamecopy == '\0') {
+               if (!dols)
+                       goto exit;
+
+               dols = LS_ROOT;
+       } else if ((idx = dirdelim(fnamecopy)) >= 0) {
+               isdir = 1;
+               fnamecopy[idx] = '\0';
+               subname = fnamecopy + idx + 1;
+
+               /* Handle multiple delimiters */
+               while (ISDIRDELIM(*subname))
+                       subname++;
+       } else if (dols) {
+               isdir = 1;
+       }
+
+       j = 0;
+       while (1) {
+               int i;
+
+               if (j == 0) {
+                       debug("FAT read sect=%d, clust_size=%d, DIRENTSPERBLOCK=%zd\n",
+                               cursect, mydata->clust_size, DIRENTSPERBLOCK);
+
+                       if (disk_read(cursect,
+                                       (mydata->fatsize == 32) ?
+                                       (mydata->clust_size) :
+                                       PREFETCH_BLOCKS,
+                                       do_fat_read_at_block) < 0) {
+                               debug("Error: reading rootdir block\n");
+                               goto exit;
                        }
-                       if (doit) {
-                           if (dirc == ' ') {
-                               printf (" %8ld   %s%c\n",
-                                       (long) FAT2CPU32 (dentptr->size),
-                                       l_name, dirc);
-                           } else {
-                               printf ("            %s%c\n", l_name, dirc);
-                           }
+
+                       dentptr = (dir_entry *) do_fat_read_at_block;
+               }
+
+               for (i = 0; i < DIRENTSPERBLOCK; i++) {
+                       char s_name[14], l_name[VFAT_MAXLEN_BYTES];
+                       __u8 csum;
+
+                       l_name[0] = '\0';
+                       if (dentptr->name[0] == DELETED_FLAG) {
+                               dentptr++;
+                               continue;
                        }
-                       dentptr++;
-                       continue;
-                   }
-                   FAT_DPRINT ("Rootvfatname: |%s|\n", l_name);
-               } else
+
+                       csum = mkcksum(dentptr->name, dentptr->ext);
+                       if (dentptr->attr & ATTR_VOLUME) {
+#ifdef CONFIG_SUPPORT_VFAT
+                               if ((dentptr->attr & ATTR_VFAT) == ATTR_VFAT &&
+                                   (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) {
+                                       prevcksum =
+                                               ((dir_slot *)dentptr)->alias_checksum;
+
+                                       get_vfatname(mydata,
+                                                    root_cluster,
+                                                    do_fat_read_at_block,
+                                                    dentptr, l_name);
+
+                                       if (dols == LS_ROOT) {
+                                               char dirc;
+                                               int doit = 0;
+                                               int isdir =
+                                                       (dentptr->attr & ATTR_DIR);
+
+                                               if (isdir) {
+                                                       dirs++;
+                                                       dirc = '/';
+                                                       doit = 1;
+                                               } else {
+                                                       dirc = ' ';
+                                                       if (l_name[0] != 0) {
+                                                               files++;
+                                                               doit = 1;
+                                                       }
+                                               }
+                                               if (doit) {
+                                                       if (dirc == ' ') {
+                                                               printf(" %8ld   %s%c\n",
+                                                                       (long)FAT2CPU32(dentptr->size),
+                                                                       l_name,
+                                                                       dirc);
+                                                       } else {
+                                                               printf("            %s%c\n",
+                                                                       l_name,
+                                                                       dirc);
+                                                       }
+                                               }
+                                               dentptr++;
+                                               continue;
+                                       }
+                                       debug("Rootvfatname: |%s|\n",
+                                              l_name);
+                               } else
 #endif
-               {
-                   /* Volume label or VFAT entry */
-                   dentptr++;
-                   continue;
-               }
-           } else if (dentptr->name[0] == 0) {
-               FAT_DPRINT ("RootDentname == NULL - %d\n", i);
-               if (dols == LS_ROOT) {
-                   printf ("\n%d file(s), %d dir(s)\n\n", files, dirs);
-                   return 0;
-               }
-               return -1;
-           }
+                               {
+                                       /* Volume label or VFAT entry */
+                                       dentptr++;
+                                       continue;
+                               }
+                       } else if (dentptr->name[0] == 0) {
+                               debug("RootDentname == NULL - %d\n", i);
+                               if (dols == LS_ROOT) {
+                                       printf("\n%d file(s), %d dir(s)\n\n",
+                                               files, dirs);
+                                       ret = 0;
+                               }
+                               goto exit;
+                       }
 #ifdef CONFIG_SUPPORT_VFAT
-           else if (dols == LS_ROOT
-                    && mkcksum (dentptr->name) == prevcksum) {
-               dentptr++;
-               continue;
-           }
+                       else if (dols == LS_ROOT && csum == prevcksum) {
+                               prevcksum = 0xffff;
+                               dentptr++;
+                               continue;
+                       }
 #endif
-           get_name (dentptr, s_name);
-           if (dols == LS_ROOT) {
-               int isdir = (dentptr->attr & ATTR_DIR);
-               char dirc;
-               int doit = 0;
-
-               if (isdir) {
-                   dirc = '/';
-                   if (s_name[0] != 0) {
-                       dirs++;
-                       doit = 1;
-                   }
+                       get_name(dentptr, s_name);
+
+                       if (dols == LS_ROOT) {
+                               int isdir = (dentptr->attr & ATTR_DIR);
+                               char dirc;
+                               int doit = 0;
+
+                               if (isdir) {
+                                       dirc = '/';
+                                       if (s_name[0] != 0) {
+                                               dirs++;
+                                               doit = 1;
+                                       }
+                               } else {
+                                       dirc = ' ';
+                                       if (s_name[0] != 0) {
+                                               files++;
+                                               doit = 1;
+                                       }
+                               }
+                               if (doit) {
+                                       if (dirc == ' ') {
+                                               printf(" %8ld   %s%c\n",
+                                                       (long)FAT2CPU32(dentptr->size),
+                                                       s_name, dirc);
+                                       } else {
+                                               printf("            %s%c\n",
+                                                       s_name, dirc);
+                                       }
+                               }
+                               dentptr++;
+                               continue;
+                       }
+
+                       if (strcmp(fnamecopy, s_name)
+                           && strcmp(fnamecopy, l_name)) {
+                               debug("RootMismatch: |%s|%s|\n", s_name,
+                                      l_name);
+                               dentptr++;
+                               continue;
+                       }
+
+                       if (isdir && !(dentptr->attr & ATTR_DIR))
+                               goto exit;
+
+                       debug("RootName: %s", s_name);
+                       debug(", start: 0x%x", START(dentptr));
+                       debug(", size:  0x%x %s\n",
+                              FAT2CPU32(dentptr->size),
+                              isdir ? "(DIR)" : "");
+
+                       goto rootdir_done;      /* We got a match */
+               }
+               debug("END LOOP: j=%d   clust_size=%d\n", j,
+                      mydata->clust_size);
+
+               /*
+                * On FAT32 we must fetch the FAT entries for the next
+                * root directory clusters when a cluster has been
+                * completely processed.
+                */
+               ++j;
+               int rootdir_end = 0;
+               if (mydata->fatsize == 32) {
+                       if (j == mydata->clust_size) {
+                               int nxtsect = 0;
+                               int nxt_clust = 0;
+
+                               nxt_clust = get_fatent(mydata, root_cluster);
+                               rootdir_end = CHECK_CLUST(nxt_clust, 32);
+
+                               nxtsect = mydata->data_begin +
+                                       (nxt_clust * mydata->clust_size);
+
+                               root_cluster = nxt_clust;
+
+                               cursect = nxtsect;
+                               j = 0;
+                       }
                } else {
-                   dirc = ' ';
-                   if (s_name[0] != 0) {
-                       files++;
-                       doit = 1;
-                   }
+                       if (j == PREFETCH_BLOCKS)
+                               j = 0;
+
+                       rootdir_end = (++cursect - mydata->rootdir_sect >=
+                                      rootdir_size);
                }
-               if (doit) {
-                   if (dirc == ' ') {
-                       printf (" %8ld   %s%c\n",
-                               (long) FAT2CPU32 (dentptr->size), s_name,
-                               dirc);
-                   } else {
-                       printf ("            %s%c\n", s_name, dirc);
-                   }
+
+               /* If end of rootdir reached */
+               if (rootdir_end) {
+                       if (dols == LS_ROOT) {
+                               printf("\n%d file(s), %d dir(s)\n\n",
+                                      files, dirs);
+                               ret = 0;
+                       }
+                       goto exit;
                }
-               dentptr++;
-               continue;
-           }
-           if (strcmp (fnamecopy, s_name) && strcmp (fnamecopy, l_name)) {
-               FAT_DPRINT ("RootMismatch: |%s|%s|\n", s_name, l_name);
-               dentptr++;
-               continue;
-           }
-           if (isdir && !(dentptr->attr & ATTR_DIR))
-               return -1;
+       }
+rootdir_done:
 
-           FAT_DPRINT ("RootName: %s", s_name);
-           FAT_DPRINT (", start: 0x%x", START (dentptr));
-           FAT_DPRINT (", size:  0x%x %s\n",
-                       FAT2CPU32 (dentptr->size), isdir ? "(DIR)" : "");
+       firsttime = 1;
 
-           goto rootdir_done;  /* We got a match */
-       }
-       cursect++;
-    }
-  rootdir_done:
-
-    firsttime = 1;
-    while (isdir) {
-       int startsect = mydata->data_begin
-               + START (dentptr) * mydata->clust_size;
-       dir_entry dent;
-       char *nextname = NULL;
-
-       dent = *dentptr;
-       dentptr = &dent;
-
-       idx = dirdelim (subname);
-       if (idx >= 0) {
-           subname[idx] = '\0';
-           nextname = subname + idx + 1;
-           /* Handle multiple delimiters */
-           while (ISDIRDELIM (*nextname))
-               nextname++;
-           if (dols && *nextname == '\0')
-               firsttime = 0;
-       } else {
-           if (dols && firsttime) {
-               firsttime = 0;
-           } else {
-               isdir = 0;
-           }
-       }
+       while (isdir) {
+               int startsect = mydata->data_begin
+                       + START(dentptr) * mydata->clust_size;
+               dir_entry dent;
+               char *nextname = NULL;
 
-       if (get_dentfromdir (mydata, startsect, subname, dentptr,
-                            isdir ? 0 : dols) == NULL) {
-           if (dols && !isdir)
-               return 0;
-           return -1;
-       }
+               dent = *dentptr;
+               dentptr = &dent;
 
-       if (idx >= 0) {
-           if (!(dentptr->attr & ATTR_DIR))
-               return -1;
-           subname = nextname;
+               idx = dirdelim(subname);
+
+               if (idx >= 0) {
+                       subname[idx] = '\0';
+                       nextname = subname + idx + 1;
+                       /* Handle multiple delimiters */
+                       while (ISDIRDELIM(*nextname))
+                               nextname++;
+                       if (dols && *nextname == '\0')
+                               firsttime = 0;
+               } else {
+                       if (dols && firsttime) {
+                               firsttime = 0;
+                       } else {
+                               isdir = 0;
+                       }
+               }
+
+               if (get_dentfromdir(mydata, startsect, subname, dentptr,
+                                    isdir ? 0 : dols) == NULL) {
+                       if (dols && !isdir)
+                               ret = 0;
+                       goto exit;
+               }
+
+               if (isdir && !(dentptr->attr & ATTR_DIR))
+                       goto exit;
+
+               if (idx >= 0)
+                       subname = nextname;
        }
-    }
-    ret = get_contents (mydata, dentptr, buffer, maxsize);
-    FAT_DPRINT ("Size: %d, got: %ld\n", FAT2CPU32 (dentptr->size), ret);
 
-    return ret;
+       ret = get_contents(mydata, dentptr, pos, buffer, maxsize);
+       debug("Size: %d, got: %ld\n", FAT2CPU32(dentptr->size), ret);
+
+exit:
+       free(mydata->fatbuf);
+       return ret;
 }
 
+long
+do_fat_read(const char *filename, void *buffer, unsigned long maxsize, int dols)
+{
+       return do_fat_read_at(filename, 0, buffer, maxsize, dols);
+}
 
-int
-file_fat_detectfs(void)
+int file_fat_detectfs(void)
 {
-       boot_sector     bs;
-       volume_info     volinfo;
-       int             fatsize;
-       char    vol_label[12];
+       boot_sector bs;
+       volume_info volinfo;
+       int fatsize;
+       char vol_label[12];
 
-       if(cur_dev==NULL) {
+       if (cur_dev == NULL) {
                printf("No current device\n");
                return 1;
        }
+
 #if defined(CONFIG_CMD_IDE) || \
     defined(CONFIG_CMD_SATA) || \
     defined(CONFIG_CMD_SCSI) || \
     defined(CONFIG_CMD_USB) || \
     defined(CONFIG_MMC)
        printf("Interface:  ");
-       switch(cur_dev->if_type) {
-               case IF_TYPE_IDE :      printf("IDE"); break;
-               case IF_TYPE_SATA :     printf("SATA"); break;
-               case IF_TYPE_SCSI :     printf("SCSI"); break;
-               case IF_TYPE_ATAPI :    printf("ATAPI"); break;
-               case IF_TYPE_USB :      printf("USB"); break;
-               case IF_TYPE_DOC :      printf("DOC"); break;
-               case IF_TYPE_MMC :      printf("MMC"); break;
-               default :               printf("Unknown");
+       switch (cur_dev->if_type) {
+       case IF_TYPE_IDE:
+               printf("IDE");
+               break;
+       case IF_TYPE_SATA:
+               printf("SATA");
+               break;
+       case IF_TYPE_SCSI:
+               printf("SCSI");
+               break;
+       case IF_TYPE_ATAPI:
+               printf("ATAPI");
+               break;
+       case IF_TYPE_USB:
+               printf("USB");
+               break;
+       case IF_TYPE_DOC:
+               printf("DOC");
+               break;
+       case IF_TYPE_MMC:
+               printf("MMC");
+               break;
+       default:
+               printf("Unknown");
        }
-       printf("\n  Device %d: ",cur_dev->dev);
+
+       printf("\n  Device %d: ", cur_dev->dev);
        dev_print(cur_dev);
 #endif
-       if(read_bootsectandvi(&bs, &volinfo, &fatsize)) {
+
+       if (read_bootsectandvi(&bs, &volinfo, &fatsize)) {
                printf("\nNo valid FAT fs found\n");
                return 1;
        }
-       memcpy (vol_label, volinfo.volume_label, 11);
+
+       memcpy(vol_label, volinfo.volume_label, 11);
        vol_label[11] = '\0';
-       volinfo.fs_type[5]='\0';
-       printf("Partition %d: Filesystem: %s \"%s\"\n"
-                       ,cur_part,volinfo.fs_type,vol_label);
+       volinfo.fs_type[5] = '\0';
+
+       printf("Filesystem: %s \"%s\"\n", volinfo.fs_type, vol_label);
+
        return 0;
 }
 
-
-int
-file_fat_ls(const char *dir)
+int file_fat_ls(const char *dir)
 {
        return do_fat_read(dir, NULL, 0, LS_YES);
 }
 
+long file_fat_read_at(const char *filename, unsigned long pos, void *buffer,
+                     unsigned long maxsize)
+{
+       printf("reading %s\n", filename);
+       return do_fat_read_at(filename, pos, buffer, maxsize, LS_NO);
+}
 
-long
-file_fat_read(const char *filename, void *buffer, unsigned long maxsize)
+long file_fat_read(const char *filename, void *buffer, unsigned long maxsize)
 {
-       printf("reading %s\n",filename);
-       return do_fat_read(filename, buffer, maxsize, LS_NO);
+       return file_fat_read_at(filename, 0, buffer, maxsize);
 }