filesystem support

git-svn-id: svn://svn.coreboot.org/coreboot/trunk@1398 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1

1 files changed, 401 insertions, 0 deletions

diff --git a/src/stream/fs/blockdev.c b/src/stream/fs/blockdev.c
new file mode 100644
index 0000000000..336f435a25
--- /dev/null
+++ b/src/stream/fs/blockdev.c
@@ -0,0 +1,401 @@
+#include <console/console.h>
+#include <fs/fs.h>
+#include <arch/io.h>
+#include <string.h>
+#include <pc80/ide.h>
+#include <arch/byteorder.h>
+
+#define NUM_CACHE 64
+static unsigned char buf_cache[NUM_CACHE][512];
+static unsigned long cache_sect[NUM_CACHE];
+
+static char dev_name[256];
+
+int dev_type = -1;
+int dev_drive = -1;
+unsigned long part_start;
+unsigned long part_length;
+int using_devsize;
+
+unsigned long long simple_strtoull(const char *cp,char **endp,unsigned int base)
+{
+	unsigned long long result = 0,value;
+
+	if (!base) {
+		base = 10;
+		if (*cp == '0') {
+			base = 8;
+			cp++;
+			if ((*cp == 'x') && isxdigit(cp[1])) {
+				cp++;
+				base = 16;
+			}
+		}
+	}
+	while (isxdigit(*cp) && (value = isdigit(*cp) ? *cp-'0' : (islower(*cp)
+		? toupper(*cp) : *cp)-'A'+10) < base) {
+		result = result*base + value;
+		cp++;
+	}
+	if (endp)
+		*endp = (char *)cp;
+	return result;
+}
+
+unsigned long long strtoull_with_suffix(const char *cp,char **endp,unsigned int base)
+{
+	unsigned long long result;
+
+	if (!endp) {
+		return 0;
+	}
+	result = simple_strtoull(cp, endp, base);
+	switch (toupper(**endp)) {
+	case 'K':
+		result <<= 10;
+		++*endp;
+		break;
+	case 'M':
+		result <<= 20;
+		++*endp;
+		break;
+	case 'G':
+		result <<= 30;
+		++*endp;
+		break;
+	}
+	return result;
+}
+
+unsigned int get_le32(const unsigned char *p)
+{
+    return ((unsigned int) p[0] << 0)
+        | ((unsigned int) p[1] << 8)
+        | ((unsigned int) p[2] << 16)
+        | ((unsigned int) p[3] << 24);
+}
+
+static inline int has_pc_part_magic(unsigned char *sect)
+{
+    return sect[510]==0x55 && sect[511]==0xAA;
+}
+
+static inline int is_pc_extended_part(unsigned char type)
+{
+    return type==5 || type==0xf || type==0x85;
+}
+
+/* IBM-PC/MS-DOS style partitioning scheme */
+static int open_pc_partition(int part, unsigned long *start_p,
+	unsigned long *length_p)
+{
+    /* Layout of PC partition table */
+    struct pc_partition {
+	unsigned char boot;
+	unsigned char head;
+	unsigned char sector;
+	unsigned char cyl;
+	unsigned char type;
+	unsigned char e_head;
+	unsigned char e_sector;
+	unsigned char e_cyl;
+	unsigned char start_sect[4]; /* unaligned little endian */
+	unsigned char nr_sects[4]; /* ditto */
+    } *p;
+    unsigned char buf[512];
+
+    /* PC partition probe */
+    if (!devread(0, 0, sizeof buf, buf)) {
+	printk_debug("device read failed\n");
+	return 0;
+    }
+    if (!has_pc_part_magic(buf)) {
+	printk_debug("pc partition magic number not found\n");
+	//printk_debug_hexdump(buf, 512);
+	return PARTITION_UNKNOWN;
+    }
+    p = (struct pc_partition *) (buf + 0x1be);
+    if (part < 4) {
+	/* Primary partition */
+	p += part;
+	if (p->type==0 || is_pc_extended_part(p->type)) {
+	    printk_info("Partition %d does not exist\n", part+1);
+	    return 0;
+	}
+	*start_p = get_le32(p->start_sect);
+	*length_p = get_le32(p->nr_sects);
+	return 1;
+    } else {
+	/* Extended partition */
+	int i;
+	int cur_part;
+	unsigned long ext_start, cur_table;
+	/* Search for the extended partition
+	 * which contains logical partitions */
+	for (i = 0; i < 4; i++) {
+	    if (is_pc_extended_part(p[i].type))
+		break;
+	}
+	if (i >= 4) {
+	    printk_info("Extended partition not found\n");
+	    return 0;
+	}
+	printk_debug("Extended partition at %d\n", i+1);
+	/* Visit each logical partition labels */
+	ext_start = get_le32(p[i].start_sect);
+	cur_table = ext_start;
+	cur_part = 4;
+	for (;;) {
+	    printk_debug("cur_part=%d at %lu\n", cur_part, cur_table);
+	    if (!devread(cur_table, 0, sizeof buf, buf))
+		return 0;
+	    if (!has_pc_part_magic(buf)) {
+		printk_debug("no magic\n");
+		break;
+	    }
+
+	    p = (struct pc_partition *) (buf + 0x1be);
+	    /* First entry is the logical partition */
+	    if (cur_part == part) {
+		if (p->type==0) {
+		    printk_info("Partition %d is empty\n", part+1);
+		    return 0;
+		}
+		*start_p = cur_table + get_le32(p->start_sect);
+		*length_p = get_le32(p->nr_sects);
+		return 1;
+	    }
+	    /* Second entry is link to next partition */
+	    if (!is_pc_extended_part(p[1].type)) {
+		printk_debug("no link\n");
+		break;
+	    }
+	    cur_table = ext_start + get_le32(p[1].start_sect);
+
+	    cur_part++;
+	}
+	printk_info("Logical partition %d not exist\n", part+1);
+	return 0;
+    }
+}
+
+static void flush_cache(void)
+{
+    int i;
+    for (i = 0; i < NUM_CACHE; i++)
+	cache_sect[i] = (unsigned long) -1;
+}
+
+static int parse_device_name(const char *name, int *type, int *drive,
+	int *part, uint64_t *offset, uint64_t *length)
+{
+    *offset = *length = 0;
+
+    if (memcmp(name, "hd", 2) == 0) {
+	*type = DISK_IDE;
+	name += 2;
+	if (*name < 'a' || *name > 'z') {
+	    printk_info("Invalid drive\n");
+	    return 0;
+	}
+	*drive = *name - 'a';
+	name++;
+    } else if (memcmp(name, "mem", 3) == 0) {
+	*type = DISK_MEM;
+	name += 3;
+	*drive = 0;
+    } else {
+	printk_info("Unknown device type\n");
+	return 0;
+    }
+
+    *part = (int) simple_strtoull(name, (char **)&name, 0);
+
+    if (*name == '@') {
+	name++;
+	*offset = strtoull_with_suffix(name, (char **)&name, 0);
+	if (*name == ',')
+	    *length = strtoull_with_suffix(name+1, (char **)&name, 0);
+	printk_debug("offset=%#Lx length=%#Lx\n", *offset, *length);
+    }
+
+    if (*name != '\0') {
+	printk_info("Can't parse device name\n");
+	return 0;
+    }
+
+    return 1;
+}
+
+int devopen(const char *name, int *reopen)
+{
+    int type, drive, part;
+    uint64_t offset, length;
+    uint32_t disk_size = 0;
+
+    /* Don't re-open the device that's already open */
+    if (strcmp(name, dev_name) == 0) {
+	printk_debug("already open\n");
+	*reopen = 1;
+	return 1;
+    }
+    *reopen = 0;
+
+    if (!parse_device_name(name, &type, &drive, &part, &offset, &length)) {
+	printk_debug("failed to parse device name: %s\n", name);
+	return 0;
+    }
+
+    /* Do simple sanity check first */
+    if (offset & 0x1ff) {
+	printk_info("Device offset must be multiple of 512\n");
+	return 0;
+    }
+    if (length & 0x1ff) {
+	printk_info("WARNING: length is rounded up to multiple of 512\n");
+	length = (length + 0x1ff) & ~0x1ff;
+    }
+
+    switch (type) {
+    case DISK_IDE:
+	if (ide_probe(drive) != 0) {
+	    printk_debug("failed to open ide\n");
+	    return 0;
+	}
+	disk_size = (uint32_t) -1; /* FIXME */
+	break;
+    case DISK_MEM:
+	disk_size = 1 << (32 - 9); /* 4GB/512-byte */
+	break;
+    default:
+	printk_info("Unknown device type %d\n", type);
+	return 0;
+    }
+
+    if (dev_type != type || dev_drive != drive)
+	flush_cache();
+
+    /* start with whole disk */
+    dev_type = type;
+    dev_drive = drive;
+    part_start = 0;
+    part_length = disk_size;
+    using_devsize = 1;
+
+    if (part != 0) {
+	/* partition is specified */
+	int ret;
+	ret = open_pc_partition(part - 1, &part_start, &part_length);
+	if (ret == PARTITION_UNKNOWN) {
+	    ret = open_eltorito_image(part - 1, &part_start, &part_length);
+	    if (ret == PARTITION_UNKNOWN) {
+		printk_info("Unrecognized partitioning scheme\n");
+		return 0;
+	    }
+	}
+	if (ret == 0) {
+	    printk_debug("can't open partition %d\n", part);
+	    return 0;
+	}
+
+	printk_debug("Partition %d start %lu length %lu\n", part,
+		part_start, part_length);
+    }
+
+    if (offset) {
+	if (offset >= (uint64_t) part_length << 9) {
+	    printk_info("Device offset is too high\n");
+	    return 0;
+	}
+	part_start += offset >> 9;
+	part_length -= offset >> 9;
+	printk_debug("after offset: start %lu, length %lu\n", part_start, part_length);
+    }
+
+    if (length) {
+	if (length > (uint64_t) part_length << 9) {
+	    printk_info("Specified length exceeds the size of device\n");
+	    return 0;
+	}
+	part_length = length >> 9;
+	printk_debug("after length: length %lu\n", part_length);
+	using_devsize = 0;
+    }
+
+    strncpy(dev_name, name, sizeof dev_name-1);
+
+    return 1;
+}
+
+/* Read a sector from opened device with simple/stupid buffer cache */
+static void *read_sector(unsigned long sector)
+{
+    unsigned int hash;
+    void *buf;
+
+    /* If reading memory, just return the memory as the buffer */
+    if (dev_type == DISK_MEM) {
+	unsigned long phys = sector << 9;
+	//printk_debug("mem: %#lx\n", phys);
+	return (void *)phys;
+    }
+
+    /* Search in the cache */
+    hash = sector % NUM_CACHE;
+    buf = buf_cache[hash];
+    if (cache_sect[hash] != sector) {
+	cache_sect[hash] = (unsigned long) -1;
+	switch (dev_type) {
+	case DISK_IDE:
+	    if (ide_read(dev_drive, sector, buf) != 0)
+		goto readerr;
+	    break;
+	default:
+	    printk_info("read_sector: device not open\n");
+	    return 0;
+	}
+	cache_sect[hash] = sector;
+    }
+    return buf;
+
+readerr:
+    printk_info("Disk read error dev=%d drive=%d sector=%lu\n",
+	    dev_type, dev_drive, sector);
+    dev_name[0] = '\0'; /* force re-open the device next time */
+    return 0;
+}
+
+int devread(unsigned long sector, unsigned long byte_offset,
+	unsigned long byte_len, void *buf)
+{
+    char *sector_buffer;
+    char *dest = buf;
+    unsigned long len;
+
+    sector += byte_offset >> 9;
+    byte_offset &= 0x1ff;
+
+    if (sector + ((byte_len + 0x1ff) >> 9) > part_length) {
+	printk_info("Attempt to read out of device/partition\n");
+	printk_debug("sector=%lu part_length=%lu byte_len=%lu\n",
+		sector, part_length, byte_len);
+	return 0;
+    }
+
+    while (byte_len > 0) {
+	sector_buffer = read_sector(part_start + sector);
+	if (!sector_buffer) {
+	    printk_debug("read sector failed\n");
+	    return 0;
+	}
+	len = 512 - byte_offset;
+	if (len > byte_len)
+	    len = byte_len;
+	memcpy(dest, sector_buffer + byte_offset, len);
+	sector++;
+	byte_offset = 0;
+	byte_len -= len;
+	dest += len;
+    }
+    return 1;
+}