static bool
rtems_rfs_check_config (rtems_rfs_file_system* fs,
const rtems_rfs_format_config* config)
{
fs->block_size = config->block_size;
if (!fs->block_size)
{
uint64_t total_size = rtems_rfs_fs_media_size (fs);
if (total_size >= GIGS (1))
{
uint32_t gigs = (total_size + GIGS (1)) / GIGS (1);
int b;
for (b = 31; b > 0; b--)
if ((gigs & (1 << b)) != 0)
break;
fs->block_size = 1 << b;
}
if (fs->block_size < 512)
fs->block_size = 512;
if (fs->block_size > (4 * 1024))
fs->block_size = (4 * 1024);
}
if ((fs->block_size % rtems_rfs_fs_media_block_size (fs)) != 0)
{
printf ("block size (%zd) is not a multiple of media block size (%" PRId32 ")\n",
fs->block_size, rtems_rfs_fs_media_block_size (fs));
return false;
}
fs->group_blocks = config->group_blocks;
if (!fs->group_blocks)
{
/*
* The number of blocks per group is defined by the number of bits in a
* block.
*/
fs->group_blocks = rtems_rfs_bitmap_numof_bits (fs->block_size);
}
if (fs->group_blocks > rtems_rfs_bitmap_numof_bits (fs->block_size))
{
printf ("group block count is higher than bits in block\n");
return false;
}
fs->blocks = rtems_rfs_fs_media_size (fs) / fs->block_size;
/*
* The bits per block sets the upper limit for the number of blocks in a
* group. The disk will be divided into groups which are the number of bits
* per block.
*/
fs->group_count = rtems_rfs_rup_quotient (rtems_rfs_fs_blocks (fs),
rtems_rfs_bits_per_block (fs));
fs->group_inodes = config->group_inodes;
if (!fs->group_inodes)
{
int inode_overhead = RTEMS_RFS_INODE_OVERHEAD_PERCENTAGE;
/*
* The number of inodes per group is set as a percentage.
*/
if (config->inode_overhead)
inode_overhead = config->inode_overhead;
fs->group_inodes = rtems_rfs_inodes_from_percent (fs, inode_overhead);
}
/*
* Round up to fill a block because the minimum allocation unit is a block.
*/
fs->inodes_per_block = rtems_rfs_fs_block_size (fs) / RTEMS_RFS_INODE_SIZE;
fs->group_inodes =
rtems_rfs_rup_quotient (fs->group_inodes,
fs->inodes_per_block) * fs->inodes_per_block;
if (fs->group_inodes > rtems_rfs_bitmap_numof_bits (fs->block_size))
fs->group_inodes = rtems_rfs_bitmap_numof_bits (fs->block_size);
fs->max_name_length = config->max_name_length;
if (!fs->max_name_length)
{
fs->max_name_length = 512;
}
return true;
}
static int
rtems_rfs_fs_read_superblock (rtems_rfs_file_system* fs)
{
rtems_rfs_buffer_handle handle;
uint8_t* sb;
int group;
int rc;
rc = rtems_rfs_buffer_handle_open (fs, &handle);
if (rc > 0)
{
if (rtems_rfs_trace (RTEMS_RFS_TRACE_OPEN))
printf ("rtems-rfs: read-superblock: handle open failed: %d: %s\n",
rc, strerror (rc));
return rc;
}
rc = rtems_rfs_buffer_handle_request (fs, &handle, 0, true);
if (rc > 0)
{
if (rtems_rfs_trace (RTEMS_RFS_TRACE_OPEN))
printf ("rtems-rfs: read-superblock: request failed%d: %s\n",
rc, strerror (rc));
return rc;
}
sb = rtems_rfs_buffer_data (&handle);
#define read_sb(_o) rtems_rfs_read_u32 (sb + (_o))
if (read_sb (RTEMS_RFS_SB_OFFSET_MAGIC) != RTEMS_RFS_SB_MAGIC)
{
if (rtems_rfs_trace (RTEMS_RFS_TRACE_OPEN))
printf ("rtems-rfs: read-superblock: invalid superblock, bad magic\n");
rtems_rfs_buffer_handle_close (fs, &handle);
return EIO;
}
fs->blocks = read_sb (RTEMS_RFS_SB_OFFSET_BLOCKS);
fs->block_size = read_sb (RTEMS_RFS_SB_OFFSET_BLOCK_SIZE);
if (rtems_rfs_fs_size(fs) > rtems_rfs_fs_media_size (fs))
{
if (rtems_rfs_trace (RTEMS_RFS_TRACE_OPEN))
printf ("rtems-rfs: read-superblock: invalid superblock block/size count\n");
rtems_rfs_buffer_handle_close (fs, &handle);
return EIO;
}
if ((read_sb (RTEMS_RFS_SB_OFFSET_VERSION) & RTEMS_RFS_VERSION_MASK) !=
(RTEMS_RFS_VERSION * RTEMS_RFS_VERSION_MASK))
{
if (rtems_rfs_trace (RTEMS_RFS_TRACE_OPEN))
printf ("rtems-rfs: read-superblock: incompatible version: %08" PRIx32 " (%08" PRIx32 ")\n",
read_sb (RTEMS_RFS_SB_OFFSET_VERSION), RTEMS_RFS_VERSION_MASK);
rtems_rfs_buffer_handle_close (fs, &handle);
return EIO;
}
if (read_sb (RTEMS_RFS_SB_OFFSET_INODE_SIZE) != RTEMS_RFS_INODE_SIZE)
{
if (rtems_rfs_trace (RTEMS_RFS_TRACE_OPEN))
printf ("rtems-rfs: read-superblock: inode size mismatch: fs:%" PRId32 " target:%" PRId32 "\n",
read_sb (RTEMS_RFS_SB_OFFSET_VERSION), RTEMS_RFS_VERSION_MASK);
rtems_rfs_buffer_handle_close (fs, &handle);
return EIO;
}
fs->bad_blocks = read_sb (RTEMS_RFS_SB_OFFSET_BAD_BLOCKS);
fs->max_name_length = read_sb (RTEMS_RFS_SB_OFFSET_MAX_NAME_LENGTH);
fs->group_count = read_sb (RTEMS_RFS_SB_OFFSET_GROUPS);
fs->group_blocks = read_sb (RTEMS_RFS_SB_OFFSET_GROUP_BLOCKS);
fs->group_inodes = read_sb (RTEMS_RFS_SB_OFFSET_GROUP_INODES);
fs->blocks_per_block =
rtems_rfs_fs_block_size (fs) / sizeof (rtems_rfs_inode_block);
fs->block_map_singly_blocks =
fs->blocks_per_block * RTEMS_RFS_INODE_BLOCKS;
fs->block_map_doubly_blocks =
fs->blocks_per_block * fs->blocks_per_block * RTEMS_RFS_INODE_BLOCKS;
fs->inodes = fs->group_count * fs->group_inodes;
fs->inodes_per_block = fs->block_size / RTEMS_RFS_INODE_SIZE;
if (fs->group_blocks >
rtems_rfs_bitmap_numof_bits (rtems_rfs_fs_block_size (fs)))
{
rtems_rfs_buffer_handle_close (fs, &handle);
if (rtems_rfs_trace (RTEMS_RFS_TRACE_OPEN))
printf ("rtems-rfs: read-superblock: groups blocks larger than block bits\n");
return EIO;
}
rtems_rfs_buffer_handle_close (fs, &handle);
/*
* Change the block size to the value in the superblock.
*/
rc = rtems_rfs_buffer_setblksize (fs, rtems_rfs_fs_block_size (fs));
if (rc > 0)
{
rtems_rfs_buffer_handle_close (fs, &handle);
if (rtems_rfs_trace (RTEMS_RFS_TRACE_OPEN))
printf ("rtems-rfs: read-superblock: invalid superblock block size%d: %s\n",
rc, strerror (rc));
return rc;
}
fs->groups = calloc (fs->group_count, sizeof (rtems_rfs_group));
if (!fs->groups)
{
rtems_rfs_buffer_handle_close (fs, &handle);
if (rtems_rfs_trace (RTEMS_RFS_TRACE_OPEN))
printf ("rtems-rfs: read-superblock: no memory for group table\n");
return ENOMEM;
}
/*
* Perform each phase of group initialisation at the same time. This way we
* know how far the initialisation has gone if an error occurs and we need to
* close everything.
*/
for (group = 0; group < fs->group_count; group++)
{
rc = rtems_rfs_group_open (fs,
rtems_rfs_fs_block (fs, group, 0),
fs->group_blocks,
fs->group_inodes,
&fs->groups[group]);
if (rc > 0)
{
int g;
for (g = 0; g < group; g++)
rtems_rfs_group_close (fs, &fs->groups[g]);
rtems_rfs_buffer_handle_close (fs, &handle);
if (rtems_rfs_trace (RTEMS_RFS_TRACE_OPEN))
printf ("rtems-rfs: read-superblock: no memory for group table%d: %s\n",
rc, strerror (rc));
return rc;
}
}
return 0;
}
/**
* Return the number of bits that fit in the block size.
*/
static int
rtems_rfs_bits_per_block (rtems_rfs_file_system* fs)
{
return rtems_rfs_bitmap_numof_bits (rtems_rfs_fs_block_size (fs));
}
