static int find_group_other(struct super_block *sb, int parent_group)
{
int ngroups = sb->u.ext2_sb.s_groups_count;
struct ext2_group_desc *desc;
struct buffer_head *bh;
int group, i;
/*
* Try to place the inode in its parent directory
*/
group = parent_group;
desc = ext2_get_group_desc (sb, group, &bh);
if (desc && le16_to_cpu(desc->bg_free_inodes_count))
goto found;
/*
* Use a quadratic hash to find a group with a
* free inode
*/
for (i = 1; i < ngroups; i <<= 1) {
group += i;
if (group >= ngroups)
group -= ngroups;
desc = ext2_get_group_desc (sb, group, &bh);
if (desc && le16_to_cpu(desc->bg_free_inodes_count))
goto found;
}
/*
* That failed: try linear search for a free inode
*/
group = parent_group + 1;
for (i = 2; i < ngroups; i++) {
if (++group >= ngroups)
group = 0;
desc = ext2_get_group_desc (sb, group, &bh);
if (desc && le16_to_cpu(desc->bg_free_inodes_count))
goto found;
}
return -1;
found:
desc->bg_free_inodes_count =
cpu_to_le16(le16_to_cpu(desc->bg_free_inodes_count) - 1);
mark_buffer_dirty(bh);
return group;
}
/* alloc a new block */
int ext2_alloc_block ( unsigned int goal)
{
unsigned int block;
unsigned int block_group;
unsigned int bit;
struct ext2_group_desc *desc;
struct ext2_sb_info * sbi = EXT2_SBI();
void *bitmap;
block_group = ext2_get_group_num (goal, BLOCK);
bit = ext2_get_group_offset (goal, BLOCK);
bitmap = ext2_read_block_bitmap (block_group);
block = ext2_grab_block (bitmap, bit);
if ( !block)
ext2_error ("no free blocks any more");
desc = ext2_get_group_desc (block_group);
desc->bg_free_blocks_count --;
sbi->s_free_blocks_count --;
ext2_set_bit (bitmap, block);
return block;
}
static struct buffer_head *
read_block_bitmap(struct super_block *sb, unsigned int block_group)
{
struct ext2_group_desc * desc;
struct buffer_head * bh = NULL;
ext2_fsblk_t bitmap_blk;
desc = ext2_get_group_desc(sb, block_group, NULL);
if (!desc)
return NULL;
bitmap_blk = le32_to_cpu(desc->bg_block_bitmap);
bh = sb_getblk(sb, bitmap_blk);
if (unlikely(!bh)) {
ext2_error(sb, __func__,
"Cannot read block bitmap - "
"block_group = %d, block_bitmap = %u",
block_group, le32_to_cpu(desc->bg_block_bitmap));
return NULL;
}
if (likely(bh_uptodate_or_lock(bh)))
return bh;
if (bh_submit_read(bh) < 0) {
brelse(bh);
ext2_error(sb, __func__,
"Cannot read block bitmap - "
"block_group = %d, block_bitmap = %u",
block_group, le32_to_cpu(desc->bg_block_bitmap));
return NULL;
}
ext2_valid_block_bitmap(sb, desc, block_group, bh);
return bh;
}
static int find_group_dir(struct super_block *sb, int parent_group)
{
struct ext2_super_block * es = sb->u.ext2_sb.s_es;
int ngroups = sb->u.ext2_sb.s_groups_count;
int avefreei = le32_to_cpu(es->s_free_inodes_count) / ngroups;
struct ext2_group_desc *desc, *best_desc = NULL;
struct buffer_head *bh, *best_bh = NULL;
int group, best_group = -1;
for (group = 0; group < ngroups; group++) {
desc = ext2_get_group_desc (sb, group, &bh);
if (!desc || !desc->bg_free_inodes_count)
continue;
if (le16_to_cpu(desc->bg_free_inodes_count) < avefreei)
continue;
if (!best_desc ||
(le16_to_cpu(desc->bg_free_blocks_count) >
le16_to_cpu(best_desc->bg_free_blocks_count))) {
best_group = group;
best_desc = desc;
best_bh = bh;
}
}
if (!best_desc)
return -1;
best_desc->bg_free_inodes_count =
cpu_to_le16(le16_to_cpu(best_desc->bg_free_inodes_count) - 1);
best_desc->bg_used_dirs_count =
cpu_to_le16(le16_to_cpu(best_desc->bg_used_dirs_count) + 1);
mark_buffer_dirty(best_bh);
return best_group;
}
/*
* Read the inode allocation bitmap for a given block_group, reading
* into the specified slot in the superblock's bitmap cache.
*
* Return >=0 on success or a -ve error code.
*/
static int read_inode_bitmap (struct super_block * sb,
unsigned long block_group,
unsigned int bitmap_nr)
{
struct ext2_group_desc * gdp;
struct buffer_head * bh = NULL;
int retval = 0;
gdp = ext2_get_group_desc (sb, block_group, NULL);
if (!gdp) {
retval = -EIO;
goto error_out;
}
bh = bread (sb->s_dev, le32_to_cpu(gdp->bg_inode_bitmap), sb->s_blocksize);
if (!bh) {
ext2_error (sb, "read_inode_bitmap",
"Cannot read inode bitmap - "
"block_group = %lu, inode_bitmap = %lu",
block_group, (unsigned long) gdp->bg_inode_bitmap);
retval = -EIO;
}
/*
* On IO error, just leave a zero in the superblock's block pointer for
* this group. The IO will be retried next time.
*/
error_out:
sb->u.ext2_sb.s_inode_bitmap_number[bitmap_nr] = block_group;
sb->u.ext2_sb.s_inode_bitmap[bitmap_nr] = bh;
return retval;
}
unsigned long ext2_count_free_inodes (struct super_block * sb)
{
#ifdef EXT2FS_DEBUG
struct ext2_super_block * es;
unsigned long desc_count = 0, bitmap_count = 0;
int i;
lock_super (sb);
es = sb->u.ext2_sb.s_es;
for (i = 0; i < sb->u.ext2_sb.s_groups_count; i++) {
struct ext2_group_desc *desc = ext2_get_group_desc (sb, i, NULL);
struct buffer_head *bh;
unsigned x;
if (!desc)
continue;
desc_count += le16_to_cpu(desc->bg_free_inodes_count);
bh = load_inode_bitmap (sb, i);
if (IS_ERR(bh))
continue;
x = ext2_count_free (bh, EXT2_INODES_PER_GROUP(sb) / 8);
printk ("group %d: stored = %d, counted = %lu\n",
i, le16_to_cpu(desc->bg_free_inodes_count), x);
bitmap_count += x;
}
printk("ext2_count_free_inodes: stored = %lu, computed = %lu, %lu\n",
le32_to_cpu(es->s_free_inodes_count), desc_count, bitmap_count);
unlock_super (sb);
return desc_count;
#else
return le32_to_cpu(sb->u.ext2_sb.s_es->s_free_inodes_count);
#endif
}
/* Called at mount-time, super-block is locked */
void ext2_check_inodes_bitmap (struct super_block * sb)
{
struct ext2_super_block * es = sb->u.ext2_sb.s_es;
unsigned long desc_count = 0, bitmap_count = 0;
int i;
for (i = 0; i < sb->u.ext2_sb.s_groups_count; i++) {
struct ext2_group_desc *desc = ext2_get_group_desc(sb, i, NULL);
struct buffer_head *bh;
unsigned x;
if (!desc)
continue;
desc_count += le16_to_cpu(desc->bg_free_inodes_count);
bh = load_inode_bitmap (sb, i);
if (IS_ERR(bh))
continue;
x = ext2_count_free (bh, EXT2_INODES_PER_GROUP(sb) / 8);
if (le16_to_cpu(desc->bg_free_inodes_count) != x)
ext2_error (sb, "ext2_check_inodes_bitmap",
"Wrong free inodes count in group %d, "
"stored = %d, counted = %lu", i,
le16_to_cpu(desc->bg_free_inodes_count), x);
bitmap_count += x;
}
if (le32_to_cpu(es->s_free_inodes_count) != bitmap_count)
ext2_error (sb, "ext2_check_inodes_bitmap",
"Wrong free inodes count in super block, "
"stored = %lu, counted = %lu",
(unsigned long)le32_to_cpu(es->s_free_inodes_count),
bitmap_count);
}
int ext2_get_inode(ext2_VOLUME* volume,
unsigned int ino, struct ext2_inode *inode)
{
struct ext2_group_desc desc;
unsigned int block;
unsigned int group_id;
unsigned int offset;
struct ext2_inode *le_inode;
int i;
ino--;
group_id = ino / EXT2_INODES_PER_GROUP(volume->super);
ext2_get_group_desc(volume, group_id, &desc);
ino %= EXT2_INODES_PER_GROUP(volume->super);
block = desc.bg_inode_table;
block += ino / (EXT2_BLOCK_SIZE(volume->super) /
EXT2_INODE_SIZE(volume->super));
ext2_read_block(volume, block);
offset = ino % (EXT2_BLOCK_SIZE(volume->super) /
EXT2_INODE_SIZE(volume->super));
offset *= EXT2_INODE_SIZE(volume->super);
le_inode = (struct ext2_inode *)(volume->buffer + offset);
inode->i_mode = __le16_to_cpu(le_inode->i_mode);
inode->i_uid = __le16_to_cpu(le_inode->i_uid);
inode->i_size = __le32_to_cpu(le_inode->i_size);
inode->i_atime = __le32_to_cpu(le_inode->i_atime);
inode->i_ctime = __le32_to_cpu(le_inode->i_ctime);
inode->i_mtime = __le32_to_cpu(le_inode->i_mtime);
inode->i_dtime = __le32_to_cpu(le_inode->i_dtime);
inode->i_gid = __le16_to_cpu(le_inode->i_gid);
inode->i_links_count = __le16_to_cpu(le_inode->i_links_count);
inode->i_blocks = __le32_to_cpu(le_inode->i_blocks);
inode->i_flags = __le32_to_cpu(le_inode->i_flags);
if (S_ISLNK(inode->i_mode)) {
memcpy(inode->i_block, le_inode->i_block, EXT2_N_BLOCKS * 4);
} else {
for (i = 0; i < EXT2_N_BLOCKS; i++)
inode->i_block[i] = __le32_to_cpu(le_inode->i_block[i]);
}
inode->i_generation = __le32_to_cpu(le_inode->i_generation);
inode->i_file_acl = __le32_to_cpu(le_inode->i_file_acl);
inode->i_dir_acl = __le32_to_cpu(le_inode->i_dir_acl);
inode->i_faddr = __le32_to_cpu(le_inode->i_faddr);
inode->osd2.linux2.l_i_frag = le_inode->osd2.linux2.l_i_frag;
inode->osd2.linux2.l_i_fsize = le_inode->osd2.linux2.l_i_fsize;
inode->osd2.linux2.l_i_uid_high =
__le16_to_cpu(le_inode->osd2.linux2.l_i_uid_high);
inode->osd2.linux2.l_i_gid_high =
__le16_to_cpu(le_inode->osd2.linux2.l_i_gid_high);
return 0;
}
void ext2_free_block(struct nas *nas, uint32_t bit_returned) {
/* Return a block by turning off its bitmap bit. */
int group; /* group number of bit_returned */
int bit; /* bit_returned number within its group */
struct ext2_gd *gd;
struct ext2_file_info *fi;
struct ext2_fs_info *fsi;
fi = nas->fi->privdata;
fsi = nas->fs->fsi;
if (bit_returned >= fsi->e2sb.s_blocks_count ||
bit_returned < fsi->e2sb.s_first_data_block) {
return;
}
/* At first search group, to which bit_returned belongs to
* and figure out in what word bit is stored.
*/
group = (bit_returned - fsi->e2sb.s_first_data_block) / fsi->e2sb.s_blocks_per_group;
bit = (bit_returned - fsi->e2sb.s_first_data_block) % fsi->e2sb.s_blocks_per_group;
gd = ext2_get_group_desc(group, fsi);
/* We might be buggy (No way! :P), so check if we deallocate
* data block, but not control (system) block.
* This should never happen.
*/
if (bit_returned == gd->inode_bitmap || bit_returned == gd->block_bitmap
|| (bit_returned >= gd->inode_table
&& bit_returned < (gd->inode_table + fsi->s_itb_per_group))) {
return;
}
ext2_read_sector(nas, (char *) fi->f_buf, 1, gd->block_bitmap);
if (ext2_unsetbit(b_bitmap(fi->f_buf), bit)) {
return; /*Tried to free unused block*/
}
ext2_write_sector(nas, (char *) fi->f_buf, 1, gd->block_bitmap);
fsi->e2sb.s_free_blocks_count++;
ext2_write_sblock(nas);
gd->free_blocks_count++;
ext2_write_gdblock(nas);
if (bit_returned < fsi->s_bsearch) {
fsi->s_bsearch = bit_returned;
}
}
static int ext2_check_descriptors(struct super_block *sb)
{
int i;
struct ext2_sb_info *sbi = EXT2_SB(sb);
ext2_debug ("Checking group descriptors");
for (i = 0; i < sbi->s_groups_count; i++) {
struct ext2_group_desc *gdp = ext2_get_group_desc(sb, i, NULL);
ext2_fsblk_t first_block = ext2_group_first_block_no(sb, i);
ext2_fsblk_t last_block;
if (i == sbi->s_groups_count - 1)
last_block = le32_to_cpu(sbi->s_es->s_blocks_count) - 1;
else
last_block = first_block +
(EXT2_BLOCKS_PER_GROUP(sb) - 1);
if (le32_to_cpu(gdp->bg_block_bitmap) < first_block ||
le32_to_cpu(gdp->bg_block_bitmap) > last_block)
{
ext2_error (sb, "ext2_check_descriptors",
"Block bitmap for group %d"
" not in group (block %lu)!",
i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap));
return 0;
}
if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block ||
le32_to_cpu(gdp->bg_inode_bitmap) > last_block)
{
ext2_error (sb, "ext2_check_descriptors",
"Inode bitmap for group %d"
" not in group (block %lu)!",
i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap));
return 0;
}
if (le32_to_cpu(gdp->bg_inode_table) < first_block ||
le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 >
last_block)
{
ext2_error (sb, "ext2_check_descriptors",
"Inode table for group %d"
" not in group (block %lu)!",
i, (unsigned long) le32_to_cpu(gdp->bg_inode_table));
return 0;
}
}
return 1;
}
/*
* Read the bitmap for a given block_group, reading into the specified
* slot in the superblock's bitmap cache.
*
*/
void * ext2_read_block_bitmap(unsigned int block_group)
{
struct ext2_group_desc * desc;
void * bitmap = NULL;
desc = ext2_get_group_desc (block_group);
if (!desc)
goto error_out;
bitmap = (void *)(EXT2_BITMAP_BUFFER + (block_group << 1) * EXT2_BLOCK_SIZE);
if (!bitmap)
ext2_error ("read_block_bitmap",
"Cannot read block bitmap - "
"block_group = %d, block_bitmap = %u",
block_group, desc->bg_block_bitmap);
error_out:
return bitmap;
}
/*
* Read the inode allocation bitmap for a given block_group, reading
* into the specified slot in the superblock's bitmap cache.
*
* Return buffer_head of bitmap on success or NULL.
*/
static struct buffer_head *read_inode_bitmap (struct super_block * sb,
unsigned long block_group)
{
struct ext2_group_desc *desc;
struct buffer_head *bh = NULL;
desc = ext2_get_group_desc(sb, block_group, NULL);
if (!desc)
goto error_out;
bh = sb_bread(sb, le32_to_cpu(desc->bg_inode_bitmap));
if (!bh)
ext2_error (sb, "read_inode_bitmap",
"Cannot read inode bitmap - "
"block_group = %lu, inode_bitmap = %lu",
block_group, (unsigned long) desc->bg_inode_bitmap);
error_out:
return bh;
}
/* free the goal block, clean it */
void ext2_free_block(unsigned int block)
{
unsigned int block_group;
unsigned int bit;
struct ext2_group_desc *desc;
struct ext2_sb_info * sbi = EXT2_SBI();
void * bitmap;
block_group = ext2_get_group_num (block, BLOCK);
bit = ext2_get_group_offset (block, BLOCK);
desc = ext2_get_group_desc (block_group);
bitmap = ext2_read_block_bitmap (block_group);
if ( !ext2_clear_bit(bitmap, bit) )
ext2_error("bit %d (%d) alread cleard", bit, block_group);
desc->bg_free_blocks_count ++;
sbi->s_free_blocks_count ++;
}
void ext2_check_inodes_bitmap (struct super_block * sb)
{
struct ext2_super_block * es;
unsigned long desc_count, bitmap_count, x;
int bitmap_nr;
struct ext2_group_desc * gdp;
int i;
lock_super (sb);
es = sb->u.ext2_sb.s_es;
desc_count = 0;
bitmap_count = 0;
gdp = NULL;
for (i = 0; i < sb->u.ext2_sb.s_groups_count; i++) {
gdp = ext2_get_group_desc (sb, i, NULL);
if (!gdp)
continue;
desc_count += le16_to_cpu(gdp->bg_free_inodes_count);
bitmap_nr = load_inode_bitmap (sb, i);
if (bitmap_nr < 0)
continue;
x = ext2_count_free (sb->u.ext2_sb.s_inode_bitmap[bitmap_nr],
EXT2_INODES_PER_GROUP(sb) / 8);
if (le16_to_cpu(gdp->bg_free_inodes_count) != x)
ext2_error (sb, "ext2_check_inodes_bitmap",
"Wrong free inodes count in group %d, "
"stored = %d, counted = %lu", i,
le16_to_cpu(gdp->bg_free_inodes_count), x);
bitmap_count += x;
}
if (le32_to_cpu(es->s_free_inodes_count) != bitmap_count)
ext2_error (sb, "ext2_check_inodes_bitmap",
"Wrong free inodes count in super block, "
"stored = %lu, counted = %lu",
(unsigned long) le32_to_cpu(es->s_free_inodes_count),
bitmap_count);
unlock_super (sb);
}
unsigned long ext2_count_free_inodes (struct super_block * sb)
{
#ifdef EXT2FS_DEBUG
struct ext2_super_block * es;
unsigned long desc_count, bitmap_count, x;
int bitmap_nr;
struct ext2_group_desc * gdp;
int i;
lock_super (sb);
es = sb->u.ext2_sb.s_es;
desc_count = 0;
bitmap_count = 0;
gdp = NULL;
for (i = 0; i < sb->u.ext2_sb.s_groups_count; i++) {
gdp = ext2_get_group_desc (sb, i, NULL);
if (!gdp)
continue;
desc_count += le16_to_cpu(gdp->bg_free_inodes_count);
bitmap_nr = load_inode_bitmap (sb, i);
if (bitmap_nr < 0)
continue;
x = ext2_count_free (sb->u.ext2_sb.s_inode_bitmap[bitmap_nr],
EXT2_INODES_PER_GROUP(sb) / 8);
printk ("group %d: stored = %d, counted = %lu\n",
i, le16_to_cpu(gdp->bg_free_inodes_count), x);
bitmap_count += x;
}
printk("ext2_count_free_inodes: stored = %lu, computed = %lu, %lu\n",
le32_to_cpu(es->s_free_inodes_count), desc_count, bitmap_count);
unlock_super (sb);
return desc_count;
#else
return le32_to_cpu(sb->u.ext2_sb.s_es->s_free_inodes_count);
#endif
}
static const struct ext2_inode *
ext2_get_inode(struct fs_info *fs, int inr)
{
const struct ext2_group_desc *desc;
const char *data;
uint32_t inode_group, inode_offset;
uint32_t block_num, block_off;
inr--;
inode_group = inr / EXT2_INODES_PER_GROUP(fs);
inode_offset = inr % EXT2_INODES_PER_GROUP(fs);
desc = ext2_get_group_desc(fs, inode_group);
if (!desc)
return NULL;
block_num = desc->bg_inode_table +
inode_offset / EXT2_INODES_PER_BLOCK(fs);
block_off = inode_offset % EXT2_INODES_PER_BLOCK(fs);
data = get_cache(fs->fs_dev, block_num);
return (const struct ext2_inode *)
(data + block_off * EXT2_SB(fs)->s_inode_size);
}
static uint32_t ext2_alloc_block_bit(struct nas *nas, uint32_t goal) { /* try to allocate near this block */
uint32_t block; /* allocated block */
int word; /* word in block bitmap */
uint32_t bit;
int group;
char update_bsearch = 0;
int i;
struct ext2_gd *gd;
struct ext2_file_info *fi;
struct ext2_fs_info *fsi;
fi = nas->fi->privdata;
fsi = nas->fs->fsi;
block = NO_BLOCK;
bit = -1;
if (goal >= fsi->e2sb.s_blocks_count ||
(goal < fsi->e2sb.s_first_data_block && goal != 0)) {
goal = fsi->s_bsearch;
}
if (goal <= fsi->s_bsearch) {
/* No reason to search in a place with no free blocks */
goal = fsi->s_bsearch;
update_bsearch = DIRTY;
}
/* Figure out where to start the bit search. */
word = ((goal - fsi->e2sb.s_first_data_block) %
fsi->e2sb.s_blocks_per_group) / FS_BITCHUNK_BITS;
/* Try to allocate block at any group starting from the goal's group.
* First time goal's group is checked from the word=goal, after all
* groups checked, it's checked again from word=0, that's why "i <=".
*/
group = (goal - fsi->e2sb.s_first_data_block) / fsi->e2sb.s_blocks_per_group;
for (i = 0; i <= fsi->s_groups_count; i++, group++) {
if (group >= fsi->s_groups_count) {
group = 0;
}
gd = ext2_get_group_desc(group, fsi);
if (gd->free_blocks_count == 0) {
word = 0;
continue;
}
ext2_read_sector(nas, fi->f_buf, 1, gd->block_bitmap);
bit = ext2_setbit(b_bitmap(fi->f_buf), fsi->e2sb.s_blocks_per_group, word);
if (-1 == bit) {
if (0 == word) {
/* allocator failed to allocate a bit in bitmap with free bits.*/
return 0;
} else {
word = 0;
continue;
}
}
block = fsi->e2sb.s_first_data_block + group * fsi->e2sb.s_blocks_per_group + bit;
if (ext2_check_block_number(block, fsi, gd)) {
return 0;
}
ext2_write_sector(nas, fi->f_buf, 1, gd->block_bitmap);
fsi->e2sb.s_free_blocks_count--;
ext2_write_sblock(nas);
gd->free_blocks_count--;
ext2_write_gdblock(nas);
if (update_bsearch && block != -1 && block != NO_BLOCK) {
/* We searched from the beginning, update bsearch. */
fsi->s_bsearch = block;
}
return block;
}
return block;
}
/*
* NOTE! When we get the inode, we're the only people
* that have access to it, and as such there are no
* race conditions we have to worry about. The inode
* is not on the hash-lists, and it cannot be reached
* through the filesystem because the directory entry
* has been deleted earlier.
*
* HOWEVER: we must make sure that we get no aliases,
* which means that we have to call "clear_inode()"
* _before_ we mark the inode not in use in the inode
* bitmaps. Otherwise a newly created file might use
* the same inode number (not actually the same pointer
* though), and then we'd have two inodes sharing the
* same inode number and space on the harddisk.
*/
void ext2_free_inode (struct inode * inode)
{
struct super_block * sb = inode->i_sb;
int is_directory;
unsigned long ino;
struct buffer_head * bh;
struct buffer_head * bh2;
unsigned long block_group;
unsigned long bit;
int bitmap_nr;
struct ext2_group_desc * gdp;
struct ext2_super_block * es;
if (!inode->i_dev) {
printk ("ext2_free_inode: inode has no device\n");
return;
}
if (inode->i_count > 1) {
printk ("ext2_free_inode: inode has count=%d\n", inode->i_count);
return;
}
if (inode->i_nlink) {
printk ("ext2_free_inode: inode has nlink=%d\n",
(int) inode->i_nlink);
return;
}
if (!sb) {
printk("ext2_free_inode: inode on nonexistent device\n");
return;
}
ino = inode->i_ino;
ext2_debug ("freeing inode %lu\n", ino);
/*
* Note: we must free any quota before locking the superblock,
* as writing the quota to disk may need the lock as well.
*/
DQUOT_FREE_INODE(sb, inode);
DQUOT_DROP(inode);
lock_super (sb);
es = sb->u.ext2_sb.s_es;
if (ino < EXT2_FIRST_INO(sb) ||
ino > le32_to_cpu(es->s_inodes_count)) {
ext2_error (sb, "free_inode",
"reserved inode or nonexistent inode");
goto error_return;
}
block_group = (ino - 1) / EXT2_INODES_PER_GROUP(sb);
bit = (ino - 1) % EXT2_INODES_PER_GROUP(sb);
bitmap_nr = load_inode_bitmap (sb, block_group);
if (bitmap_nr < 0)
goto error_return;
bh = sb->u.ext2_sb.s_inode_bitmap[bitmap_nr];
is_directory = S_ISDIR(inode->i_mode);
/* Do this BEFORE marking the inode not in use */
clear_inode (inode);
/* Ok, now we can actually update the inode bitmaps.. */
if (!ext2_clear_bit (bit, bh->b_data))
ext2_warning (sb, "ext2_free_inode",
"bit already cleared for inode %lu", ino);
else {
gdp = ext2_get_group_desc (sb, block_group, &bh2);
if (gdp) {
gdp->bg_free_inodes_count =
cpu_to_le16(le16_to_cpu(gdp->bg_free_inodes_count) + 1);
if (is_directory)
gdp->bg_used_dirs_count =
cpu_to_le16(le16_to_cpu(gdp->bg_used_dirs_count) - 1);
}
mark_buffer_dirty(bh2, 1);
es->s_free_inodes_count =
cpu_to_le32(le32_to_cpu(es->s_free_inodes_count) + 1);
mark_buffer_dirty(sb->u.ext2_sb.s_sbh, 1);
}
mark_buffer_dirty(bh, 1);
if (sb->s_flags & MS_SYNCHRONOUS) {
ll_rw_block (WRITE, 1, &bh);
wait_on_buffer (bh);
}
sb->s_dirt = 1;
error_return:
unlock_super (sb);
}
/*
* There are two policies for allocating an inode. If the new inode is
* a directory, then a forward search is made for a block group with both
* free space and a low directory-to-inode ratio; if that fails, then of
* the groups with above-average free space, that group with the fewest
* directories already is chosen.
*
* For other inodes, search forward from the parent directory\'s block
* group to find a free inode.
*/
struct inode * ext2_new_inode (const struct inode * dir, int mode, int * err)
{
struct super_block * sb;
struct buffer_head * bh;
struct buffer_head * bh2;
int i, j, avefreei;
struct inode * inode;
int bitmap_nr;
struct ext2_group_desc * gdp;
struct ext2_group_desc * tmp;
struct ext2_super_block * es;
/* Cannot create files in a deleted directory */
if (!dir || !dir->i_nlink) {
*err = -EPERM;
return NULL;
}
inode = get_empty_inode ();
if (!inode) {
*err = -ENOMEM;
return NULL;
}
sb = dir->i_sb;
inode->i_sb = sb;
inode->i_flags = 0;
lock_super (sb);
es = sb->u.ext2_sb.s_es;
repeat:
gdp = NULL; i=0;
*err = -ENOSPC;
if (S_ISDIR(mode)) {
avefreei = le32_to_cpu(es->s_free_inodes_count) /
sb->u.ext2_sb.s_groups_count;
/* I am not yet convinced that this next bit is necessary.
i = dir->u.ext2_i.i_block_group;
for (j = 0; j < sb->u.ext2_sb.s_groups_count; j++) {
tmp = ext2_get_group_desc (sb, i, &bh2);
if (tmp &&
(le16_to_cpu(tmp->bg_used_dirs_count) << 8) <
le16_to_cpu(tmp->bg_free_inodes_count)) {
gdp = tmp;
break;
}
else
i = ++i % sb->u.ext2_sb.s_groups_count;
}
*/
if (!gdp) {
for (j = 0; j < sb->u.ext2_sb.s_groups_count; j++) {
tmp = ext2_get_group_desc (sb, j, &bh2);
if (tmp &&
le16_to_cpu(tmp->bg_free_inodes_count) &&
le16_to_cpu(tmp->bg_free_inodes_count) >= avefreei) {
if (!gdp ||
(le16_to_cpu(tmp->bg_free_blocks_count) >
le16_to_cpu(gdp->bg_free_blocks_count))) {
i = j;
gdp = tmp;
}
}
}
}
}
else
{
/*
* Try to place the inode in its parent directory
*/
i = dir->u.ext2_i.i_block_group;
tmp = ext2_get_group_desc (sb, i, &bh2);
if (tmp && le16_to_cpu(tmp->bg_free_inodes_count))
gdp = tmp;
else
{
/*
* Use a quadratic hash to find a group with a
* free inode
*/
for (j = 1; j < sb->u.ext2_sb.s_groups_count; j <<= 1) {
i += j;
if (i >= sb->u.ext2_sb.s_groups_count)
i -= sb->u.ext2_sb.s_groups_count;
tmp = ext2_get_group_desc (sb, i, &bh2);
if (tmp &&
le16_to_cpu(tmp->bg_free_inodes_count)) {
gdp = tmp;
break;
}
}
}
if (!gdp) {
/*
* That failed: try linear search for a free inode
*/
i = dir->u.ext2_i.i_block_group + 1;
for (j = 2; j < sb->u.ext2_sb.s_groups_count; j++) {
if (++i >= sb->u.ext2_sb.s_groups_count)
i = 0;
tmp = ext2_get_group_desc (sb, i, &bh2);
if (tmp &&
le16_to_cpu(tmp->bg_free_inodes_count)) {
gdp = tmp;
break;
}
}
}
}
if (!gdp) {
unlock_super (sb);
iput(inode);
return NULL;
}
bitmap_nr = load_inode_bitmap (sb, i);
if (bitmap_nr < 0) {
unlock_super (sb);
iput(inode);
*err = -EIO;
return NULL;
}
bh = sb->u.ext2_sb.s_inode_bitmap[bitmap_nr];
if ((j = ext2_find_first_zero_bit ((unsigned long *) bh->b_data,
EXT2_INODES_PER_GROUP(sb))) <
EXT2_INODES_PER_GROUP(sb)) {
if (ext2_set_bit (j, bh->b_data)) {
ext2_warning (sb, "ext2_new_inode",
"bit already set for inode %d", j);
goto repeat;
}
mark_buffer_dirty(bh, 1);
if (sb->s_flags & MS_SYNCHRONOUS) {
ll_rw_block (WRITE, 1, &bh);
wait_on_buffer (bh);
}
} else {
if (le16_to_cpu(gdp->bg_free_inodes_count) != 0) {
ext2_error (sb, "ext2_new_inode",
"Free inodes count corrupted in group %d",
i);
unlock_super (sb);
iput (inode);
return NULL;
}
goto repeat;
}
j += i * EXT2_INODES_PER_GROUP(sb) + 1;
if (j < EXT2_FIRST_INO(sb) || j > le32_to_cpu(es->s_inodes_count)) {
ext2_error (sb, "ext2_new_inode",
"reserved inode or inode > inodes count - "
"block_group = %d,inode=%d", i, j);
unlock_super (sb);
iput (inode);
return NULL;
}
gdp->bg_free_inodes_count =
cpu_to_le16(le16_to_cpu(gdp->bg_free_inodes_count) - 1);
if (S_ISDIR(mode))
gdp->bg_used_dirs_count =
cpu_to_le16(le16_to_cpu(gdp->bg_used_dirs_count) + 1);
mark_buffer_dirty(bh2, 1);
es->s_free_inodes_count =
cpu_to_le32(le32_to_cpu(es->s_free_inodes_count) - 1);
mark_buffer_dirty(sb->u.ext2_sb.s_sbh, 1);
sb->s_dirt = 1;
inode->i_mode = mode;
inode->i_sb = sb;
inode->i_nlink = 1;
inode->i_dev = sb->s_dev;
inode->i_uid = current->fsuid;
if (test_opt (sb, GRPID))
inode->i_gid = dir->i_gid;
else if (dir->i_mode & S_ISGID) {
inode->i_gid = dir->i_gid;
if (S_ISDIR(mode))
mode |= S_ISGID;
} else
inode->i_gid = current->fsgid;
inode->i_ino = j;
inode->i_blksize = PAGE_SIZE; /* This is the optimal IO size (for stat), not the fs block size */
inode->i_blocks = 0;
inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
inode->u.ext2_i.i_new_inode = 1;
inode->u.ext2_i.i_flags = dir->u.ext2_i.i_flags;
if (S_ISLNK(mode))
inode->u.ext2_i.i_flags &= ~(EXT2_IMMUTABLE_FL | EXT2_APPEND_FL);
inode->u.ext2_i.i_faddr = 0;
inode->u.ext2_i.i_frag_no = 0;
inode->u.ext2_i.i_frag_size = 0;
inode->u.ext2_i.i_file_acl = 0;
inode->u.ext2_i.i_dir_acl = 0;
inode->u.ext2_i.i_dtime = 0;
inode->u.ext2_i.i_block_group = i;
inode->i_op = NULL;
if (inode->u.ext2_i.i_flags & EXT2_SYNC_FL)
inode->i_flags |= MS_SYNCHRONOUS;
insert_inode_hash(inode);
mark_inode_dirty(inode);
inc_inode_version (inode, gdp, mode);
unlock_super (sb);
if(DQUOT_ALLOC_INODE(sb, inode)) {
sb->dq_op->drop(inode);
inode->i_nlink = 0;
iput(inode);
*err = -EDQUOT;
return NULL;
}
ext2_debug ("allocating inode %lu\n", inode->i_ino);
*err = 0;
return inode;
}
struct inode * ext2_new_inode (const struct inode * dir, int mode)
{
struct super_block * sb;
struct buffer_head * bh;
struct buffer_head * bh2;
int group, i;
ino_t ino;
struct inode * inode;
struct ext2_group_desc * desc;
struct ext2_super_block * es;
int err;
sb = dir->i_sb;
inode = new_inode(sb);
if (!inode)
return ERR_PTR(-ENOMEM);
lock_super (sb);
es = sb->u.ext2_sb.s_es;
repeat:
if (S_ISDIR(mode))
group = find_group_dir(sb, dir->u.ext2_i.i_block_group);
else
group = find_group_other(sb, dir->u.ext2_i.i_block_group);
err = -ENOSPC;
if (group == -1)
goto fail;
err = -EIO;
bh = load_inode_bitmap (sb, group);
if (IS_ERR(bh))
goto fail2;
i = ext2_find_first_zero_bit ((unsigned long *) bh->b_data,
EXT2_INODES_PER_GROUP(sb));
if (i >= EXT2_INODES_PER_GROUP(sb))
goto bad_count;
ext2_set_bit (i, bh->b_data);
mark_buffer_dirty(bh);
if (sb->s_flags & MS_SYNCHRONOUS) {
ll_rw_block (WRITE, 1, &bh);
wait_on_buffer (bh);
}
ino = group * EXT2_INODES_PER_GROUP(sb) + i + 1;
if (ino < EXT2_FIRST_INO(sb) || ino > le32_to_cpu(es->s_inodes_count)) {
ext2_error (sb, "ext2_new_inode",
"reserved inode or inode > inodes count - "
"block_group = %d,inode=%ld", group, ino);
err = -EIO;
goto fail2;
}
es->s_free_inodes_count =
cpu_to_le32(le32_to_cpu(es->s_free_inodes_count) - 1);
mark_buffer_dirty(sb->u.ext2_sb.s_sbh);
sb->s_dirt = 1;
inode->i_uid = current->fsuid;
if (test_opt (sb, GRPID))
inode->i_gid = dir->i_gid;
else if (dir->i_mode & S_ISGID) {
inode->i_gid = dir->i_gid;
if (S_ISDIR(mode))
mode |= S_ISGID;
} else
inode->i_gid = current->fsgid;
inode->i_mode = mode;
inode->i_ino = ino;
inode->i_blksize = PAGE_SIZE; /* This is the optimal IO size (for stat), not the fs block size */
inode->i_blocks = 0;
inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
inode->u.ext2_i.i_new_inode = 1;
inode->u.ext2_i.i_flags = dir->u.ext2_i.i_flags & ~EXT2_BTREE_FL;
if (S_ISLNK(mode))
inode->u.ext2_i.i_flags &= ~(EXT2_IMMUTABLE_FL|EXT2_APPEND_FL);
inode->u.ext2_i.i_block_group = group;
if (inode->u.ext2_i.i_flags & EXT2_SYNC_FL)
inode->i_flags |= S_SYNC;
insert_inode_hash(inode);
inode->i_generation = event++;
mark_inode_dirty(inode);
unlock_super (sb);
if(DQUOT_ALLOC_INODE(inode)) {
DQUOT_DROP(inode);
inode->i_flags |= S_NOQUOTA;
inode->i_nlink = 0;
iput(inode);
return ERR_PTR(-EDQUOT);
}
ext2_debug ("allocating inode %lu\n", inode->i_ino);
return inode;
fail2:
desc = ext2_get_group_desc (sb, group, &bh2);
desc->bg_free_inodes_count =
cpu_to_le16(le16_to_cpu(desc->bg_free_inodes_count) + 1);
if (S_ISDIR(mode))
desc->bg_used_dirs_count =
cpu_to_le16(le16_to_cpu(desc->bg_used_dirs_count) - 1);
mark_buffer_dirty(bh2);
fail:
unlock_super(sb);
make_bad_inode(inode);
iput(inode);
return ERR_PTR(err);
bad_count:
ext2_error (sb, "ext2_new_inode",
"Free inodes count corrupted in group %d",
group);
/* Is it really ENOSPC? */
err = -ENOSPC;
if (sb->s_flags & MS_RDONLY)
goto fail;
desc = ext2_get_group_desc (sb, group, &bh2);
desc->bg_free_inodes_count = 0;
mark_buffer_dirty(bh2);
goto repeat;
}
/*
* NOTE! When we get the inode, we're the only people
* that have access to it, and as such there are no
* race conditions we have to worry about. The inode
* is not on the hash-lists, and it cannot be reached
* through the filesystem because the directory entry
* has been deleted earlier.
*
* HOWEVER: we must make sure that we get no aliases,
* which means that we have to call "clear_inode()"
* _before_ we mark the inode not in use in the inode
* bitmaps. Otherwise a newly created file might use
* the same inode number (not actually the same pointer
* though), and then we'd have two inodes sharing the
* same inode number and space on the harddisk.
*/
void ext2_free_inode (struct inode * inode)
{
struct super_block * sb = inode->i_sb;
int is_directory;
unsigned long ino;
struct buffer_head * bh;
struct buffer_head * bh2;
unsigned long block_group;
unsigned long bit;
struct ext2_group_desc * desc;
struct ext2_super_block * es;
ino = inode->i_ino;
ext2_debug ("freeing inode %lu\n", ino);
/*
* Note: we must free any quota before locking the superblock,
* as writing the quota to disk may need the lock as well.
*/
if (!is_bad_inode(inode)) {
/* Quota is already initialized in iput() */
DQUOT_FREE_INODE(inode);
DQUOT_DROP(inode);
}
lock_super (sb);
es = sb->u.ext2_sb.s_es;
is_directory = S_ISDIR(inode->i_mode);
/* Do this BEFORE marking the inode not in use or returning an error */
clear_inode (inode);
if (ino < EXT2_FIRST_INO(sb) ||
ino > le32_to_cpu(es->s_inodes_count)) {
ext2_error (sb, "ext2_free_inode",
"reserved or nonexistent inode %lu", ino);
goto error_return;
}
block_group = (ino - 1) / EXT2_INODES_PER_GROUP(sb);
bit = (ino - 1) % EXT2_INODES_PER_GROUP(sb);
bh = load_inode_bitmap (sb, block_group);
if (IS_ERR(bh))
goto error_return;
/* Ok, now we can actually update the inode bitmaps.. */
if (!ext2_clear_bit (bit, bh->b_data))
ext2_error (sb, "ext2_free_inode",
"bit already cleared for inode %lu", ino);
else {
desc = ext2_get_group_desc (sb, block_group, &bh2);
if (desc) {
desc->bg_free_inodes_count =
cpu_to_le16(le16_to_cpu(desc->bg_free_inodes_count) + 1);
if (is_directory)
desc->bg_used_dirs_count =
cpu_to_le16(le16_to_cpu(desc->bg_used_dirs_count) - 1);
}
mark_buffer_dirty(bh2);
es->s_free_inodes_count =
cpu_to_le32(le32_to_cpu(es->s_free_inodes_count) + 1);
mark_buffer_dirty(sb->u.ext2_sb.s_sbh);
}
mark_buffer_dirty(bh);
if (sb->s_flags & MS_SYNCHRONOUS) {
ll_rw_block (WRITE, 1, &bh);
wait_on_buffer (bh);
}
sb->s_dirt = 1;
error_return:
unlock_super (sb);
}