diff options
Diffstat (limited to 'ANDROID_3.4.5/fs/ext4/resize.c')
| -rw-r--r-- | ANDROID_3.4.5/fs/ext4/resize.c | 1689 |
1 files changed, 0 insertions, 1689 deletions
diff --git a/ANDROID_3.4.5/fs/ext4/resize.c b/ANDROID_3.4.5/fs/ext4/resize.c deleted file mode 100644 index 53589ff8..00000000 --- a/ANDROID_3.4.5/fs/ext4/resize.c +++ /dev/null @@ -1,1689 +0,0 @@ -/* - * linux/fs/ext4/resize.c - * - * Support for resizing an ext4 filesystem while it is mounted. - * - * Copyright (C) 2001, 2002 Andreas Dilger <adilger@clusterfs.com> - * - * This could probably be made into a module, because it is not often in use. - */ - - -#define EXT4FS_DEBUG - -#include <linux/errno.h> -#include <linux/slab.h> - -#include "ext4_jbd2.h" - -int ext4_resize_begin(struct super_block *sb) -{ - int ret = 0; - - if (!capable(CAP_SYS_RESOURCE)) - return -EPERM; - - /* - * We are not allowed to do online-resizing on a filesystem mounted - * with error, because it can destroy the filesystem easily. - */ - if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) { - ext4_warning(sb, "There are errors in the filesystem, " - "so online resizing is not allowed\n"); - return -EPERM; - } - - if (test_and_set_bit_lock(EXT4_RESIZING, &EXT4_SB(sb)->s_resize_flags)) - ret = -EBUSY; - - return ret; -} - -void ext4_resize_end(struct super_block *sb) -{ - clear_bit_unlock(EXT4_RESIZING, &EXT4_SB(sb)->s_resize_flags); - smp_mb__after_clear_bit(); -} - -#define outside(b, first, last) ((b) < (first) || (b) >= (last)) -#define inside(b, first, last) ((b) >= (first) && (b) < (last)) - -static int verify_group_input(struct super_block *sb, - struct ext4_new_group_data *input) -{ - struct ext4_sb_info *sbi = EXT4_SB(sb); - struct ext4_super_block *es = sbi->s_es; - ext4_fsblk_t start = ext4_blocks_count(es); - ext4_fsblk_t end = start + input->blocks_count; - ext4_group_t group = input->group; - ext4_fsblk_t itend = input->inode_table + sbi->s_itb_per_group; - unsigned overhead = ext4_bg_has_super(sb, group) ? - (1 + ext4_bg_num_gdb(sb, group) + - le16_to_cpu(es->s_reserved_gdt_blocks)) : 0; - ext4_fsblk_t metaend = start + overhead; - struct buffer_head *bh = NULL; - ext4_grpblk_t free_blocks_count, offset; - int err = -EINVAL; - - input->free_blocks_count = free_blocks_count = - input->blocks_count - 2 - overhead - sbi->s_itb_per_group; - - if (test_opt(sb, DEBUG)) - printk(KERN_DEBUG "EXT4-fs: adding %s group %u: %u blocks " - "(%d free, %u reserved)\n", - ext4_bg_has_super(sb, input->group) ? "normal" : - "no-super", input->group, input->blocks_count, - free_blocks_count, input->reserved_blocks); - - ext4_get_group_no_and_offset(sb, start, NULL, &offset); - if (group != sbi->s_groups_count) - ext4_warning(sb, "Cannot add at group %u (only %u groups)", - input->group, sbi->s_groups_count); - else if (offset != 0) - ext4_warning(sb, "Last group not full"); - else if (input->reserved_blocks > input->blocks_count / 5) - ext4_warning(sb, "Reserved blocks too high (%u)", - input->reserved_blocks); - else if (free_blocks_count < 0) - ext4_warning(sb, "Bad blocks count %u", - input->blocks_count); - else if (!(bh = sb_bread(sb, end - 1))) - ext4_warning(sb, "Cannot read last block (%llu)", - end - 1); - else if (outside(input->block_bitmap, start, end)) - ext4_warning(sb, "Block bitmap not in group (block %llu)", - (unsigned long long)input->block_bitmap); - else if (outside(input->inode_bitmap, start, end)) - ext4_warning(sb, "Inode bitmap not in group (block %llu)", - (unsigned long long)input->inode_bitmap); - else if (outside(input->inode_table, start, end) || - outside(itend - 1, start, end)) - ext4_warning(sb, "Inode table not in group (blocks %llu-%llu)", - (unsigned long long)input->inode_table, itend - 1); - else if (input->inode_bitmap == input->block_bitmap) - ext4_warning(sb, "Block bitmap same as inode bitmap (%llu)", - (unsigned long long)input->block_bitmap); - else if (inside(input->block_bitmap, input->inode_table, itend)) - ext4_warning(sb, "Block bitmap (%llu) in inode table " - "(%llu-%llu)", - (unsigned long long)input->block_bitmap, - (unsigned long long)input->inode_table, itend - 1); - else if (inside(input->inode_bitmap, input->inode_table, itend)) - ext4_warning(sb, "Inode bitmap (%llu) in inode table " - "(%llu-%llu)", - (unsigned long long)input->inode_bitmap, - (unsigned long long)input->inode_table, itend - 1); - else if (inside(input->block_bitmap, start, metaend)) - ext4_warning(sb, "Block bitmap (%llu) in GDT table (%llu-%llu)", - (unsigned long long)input->block_bitmap, - start, metaend - 1); - else if (inside(input->inode_bitmap, start, metaend)) - ext4_warning(sb, "Inode bitmap (%llu) in GDT table (%llu-%llu)", - (unsigned long long)input->inode_bitmap, - start, metaend - 1); - else if (inside(input->inode_table, start, metaend) || - inside(itend - 1, start, metaend)) - ext4_warning(sb, "Inode table (%llu-%llu) overlaps GDT table " - "(%llu-%llu)", - (unsigned long long)input->inode_table, - itend - 1, start, metaend - 1); - else - err = 0; - brelse(bh); - - return err; -} - -/* - * ext4_new_flex_group_data is used by 64bit-resize interface to add a flex - * group each time. - */ -struct ext4_new_flex_group_data { - struct ext4_new_group_data *groups; /* new_group_data for groups - in the flex group */ - __u16 *bg_flags; /* block group flags of groups - in @groups */ - ext4_group_t count; /* number of groups in @groups - */ -}; - -/* - * alloc_flex_gd() allocates a ext4_new_flex_group_data with size of - * @flexbg_size. - * - * Returns NULL on failure otherwise address of the allocated structure. - */ -static struct ext4_new_flex_group_data *alloc_flex_gd(unsigned long flexbg_size) -{ - struct ext4_new_flex_group_data *flex_gd; - - flex_gd = kmalloc(sizeof(*flex_gd), GFP_NOFS); - if (flex_gd == NULL) - goto out3; - - if (flexbg_size >= UINT_MAX / sizeof(struct ext4_new_flex_group_data)) - goto out2; - flex_gd->count = flexbg_size; - - flex_gd->groups = kmalloc(sizeof(struct ext4_new_group_data) * - flexbg_size, GFP_NOFS); - if (flex_gd->groups == NULL) - goto out2; - - flex_gd->bg_flags = kmalloc(flexbg_size * sizeof(__u16), GFP_NOFS); - if (flex_gd->bg_flags == NULL) - goto out1; - - return flex_gd; - -out1: - kfree(flex_gd->groups); -out2: - kfree(flex_gd); -out3: - return NULL; -} - -static void free_flex_gd(struct ext4_new_flex_group_data *flex_gd) -{ - kfree(flex_gd->bg_flags); - kfree(flex_gd->groups); - kfree(flex_gd); -} - -/* - * ext4_alloc_group_tables() allocates block bitmaps, inode bitmaps - * and inode tables for a flex group. - * - * This function is used by 64bit-resize. Note that this function allocates - * group tables from the 1st group of groups contained by @flexgd, which may - * be a partial of a flex group. - * - * @sb: super block of fs to which the groups belongs - */ -static void ext4_alloc_group_tables(struct super_block *sb, - struct ext4_new_flex_group_data *flex_gd, - int flexbg_size) -{ - struct ext4_new_group_data *group_data = flex_gd->groups; - struct ext4_super_block *es = EXT4_SB(sb)->s_es; - ext4_fsblk_t start_blk; - ext4_fsblk_t last_blk; - ext4_group_t src_group; - ext4_group_t bb_index = 0; - ext4_group_t ib_index = 0; - ext4_group_t it_index = 0; - ext4_group_t group; - ext4_group_t last_group; - unsigned overhead; - - BUG_ON(flex_gd->count == 0 || group_data == NULL); - - src_group = group_data[0].group; - last_group = src_group + flex_gd->count - 1; - - BUG_ON((flexbg_size > 1) && ((src_group & ~(flexbg_size - 1)) != - (last_group & ~(flexbg_size - 1)))); -next_group: - group = group_data[0].group; - start_blk = ext4_group_first_block_no(sb, src_group); - last_blk = start_blk + group_data[src_group - group].blocks_count; - - overhead = ext4_bg_has_super(sb, src_group) ? - (1 + ext4_bg_num_gdb(sb, src_group) + - le16_to_cpu(es->s_reserved_gdt_blocks)) : 0; - - start_blk += overhead; - - BUG_ON(src_group >= group_data[0].group + flex_gd->count); - /* We collect contiguous blocks as much as possible. */ - src_group++; - for (; src_group <= last_group; src_group++) - if (!ext4_bg_has_super(sb, src_group)) - last_blk += group_data[src_group - group].blocks_count; - else - break; - - /* Allocate block bitmaps */ - for (; bb_index < flex_gd->count; bb_index++) { - if (start_blk >= last_blk) - goto next_group; - group_data[bb_index].block_bitmap = start_blk++; - ext4_get_group_no_and_offset(sb, start_blk - 1, &group, NULL); - group -= group_data[0].group; - group_data[group].free_blocks_count--; - if (flexbg_size > 1) - flex_gd->bg_flags[group] &= ~EXT4_BG_BLOCK_UNINIT; - } - - /* Allocate inode bitmaps */ - for (; ib_index < flex_gd->count; ib_index++) { - if (start_blk >= last_blk) - goto next_group; - group_data[ib_index].inode_bitmap = start_blk++; - ext4_get_group_no_and_offset(sb, start_blk - 1, &group, NULL); - group -= group_data[0].group; - group_data[group].free_blocks_count--; - if (flexbg_size > 1) - flex_gd->bg_flags[group] &= ~EXT4_BG_BLOCK_UNINIT; - } - - /* Allocate inode tables */ - for (; it_index < flex_gd->count; it_index++) { - if (start_blk + EXT4_SB(sb)->s_itb_per_group > last_blk) - goto next_group; - group_data[it_index].inode_table = start_blk; - ext4_get_group_no_and_offset(sb, start_blk, &group, NULL); - group -= group_data[0].group; - group_data[group].free_blocks_count -= - EXT4_SB(sb)->s_itb_per_group; - if (flexbg_size > 1) - flex_gd->bg_flags[group] &= ~EXT4_BG_BLOCK_UNINIT; - - start_blk += EXT4_SB(sb)->s_itb_per_group; - } - - if (test_opt(sb, DEBUG)) { - int i; - group = group_data[0].group; - - printk(KERN_DEBUG "EXT4-fs: adding a flex group with " - "%d groups, flexbg size is %d:\n", flex_gd->count, - flexbg_size); - - for (i = 0; i < flex_gd->count; i++) { - printk(KERN_DEBUG "adding %s group %u: %u " - "blocks (%d free)\n", - ext4_bg_has_super(sb, group + i) ? "normal" : - "no-super", group + i, - group_data[i].blocks_count, - group_data[i].free_blocks_count); - } - } -} - -static struct buffer_head *bclean(handle_t *handle, struct super_block *sb, - ext4_fsblk_t blk) -{ - struct buffer_head *bh; - int err; - - bh = sb_getblk(sb, blk); - if (!bh) - return ERR_PTR(-EIO); - if ((err = ext4_journal_get_write_access(handle, bh))) { - brelse(bh); - bh = ERR_PTR(err); - } else { - memset(bh->b_data, 0, sb->s_blocksize); - set_buffer_uptodate(bh); - } - - return bh; -} - -/* - * If we have fewer than thresh credits, extend by EXT4_MAX_TRANS_DATA. - * If that fails, restart the transaction & regain write access for the - * buffer head which is used for block_bitmap modifications. - */ -static int extend_or_restart_transaction(handle_t *handle, int thresh) -{ - int err; - - if (ext4_handle_has_enough_credits(handle, thresh)) - return 0; - - err = ext4_journal_extend(handle, EXT4_MAX_TRANS_DATA); - if (err < 0) - return err; - if (err) { - err = ext4_journal_restart(handle, EXT4_MAX_TRANS_DATA); - if (err) - return err; - } - - return 0; -} - -/* - * set_flexbg_block_bitmap() mark @count blocks starting from @block used. - * - * Helper function for ext4_setup_new_group_blocks() which set . - * - * @sb: super block - * @handle: journal handle - * @flex_gd: flex group data - */ -static int set_flexbg_block_bitmap(struct super_block *sb, handle_t *handle, - struct ext4_new_flex_group_data *flex_gd, - ext4_fsblk_t block, ext4_group_t count) -{ - ext4_group_t count2; - - ext4_debug("mark blocks [%llu/%u] used\n", block, count); - for (count2 = count; count > 0; count -= count2, block += count2) { - ext4_fsblk_t start; - struct buffer_head *bh; - ext4_group_t group; - int err; - - ext4_get_group_no_and_offset(sb, block, &group, NULL); - start = ext4_group_first_block_no(sb, group); - group -= flex_gd->groups[0].group; - - count2 = sb->s_blocksize * 8 - (block - start); - if (count2 > count) - count2 = count; - - if (flex_gd->bg_flags[group] & EXT4_BG_BLOCK_UNINIT) { - BUG_ON(flex_gd->count > 1); - continue; - } - - err = extend_or_restart_transaction(handle, 1); - if (err) - return err; - - bh = sb_getblk(sb, flex_gd->groups[group].block_bitmap); - if (!bh) - return -EIO; - - err = ext4_journal_get_write_access(handle, bh); - if (err) - return err; - ext4_debug("mark block bitmap %#04llx (+%llu/%u)\n", block, - block - start, count2); - ext4_set_bits(bh->b_data, block - start, count2); - - err = ext4_handle_dirty_metadata(handle, NULL, bh); - if (unlikely(err)) - return err; - brelse(bh); - } - - return 0; -} - -/* - * Set up the block and inode bitmaps, and the inode table for the new groups. - * This doesn't need to be part of the main transaction, since we are only - * changing blocks outside the actual filesystem. We still do journaling to - * ensure the recovery is correct in case of a failure just after resize. - * If any part of this fails, we simply abort the resize. - * - * setup_new_flex_group_blocks handles a flex group as follow: - * 1. copy super block and GDT, and initialize group tables if necessary. - * In this step, we only set bits in blocks bitmaps for blocks taken by - * super block and GDT. - * 2. allocate group tables in block bitmaps, that is, set bits in block - * bitmap for blocks taken by group tables. - */ -static int setup_new_flex_group_blocks(struct super_block *sb, - struct ext4_new_flex_group_data *flex_gd) -{ - int group_table_count[] = {1, 1, EXT4_SB(sb)->s_itb_per_group}; - ext4_fsblk_t start; - ext4_fsblk_t block; - struct ext4_sb_info *sbi = EXT4_SB(sb); - struct ext4_super_block *es = sbi->s_es; - struct ext4_new_group_data *group_data = flex_gd->groups; - __u16 *bg_flags = flex_gd->bg_flags; - handle_t *handle; - ext4_group_t group, count; - struct buffer_head *bh = NULL; - int reserved_gdb, i, j, err = 0, err2; - - BUG_ON(!flex_gd->count || !group_data || - group_data[0].group != sbi->s_groups_count); - - reserved_gdb = le16_to_cpu(es->s_reserved_gdt_blocks); - - /* This transaction may be extended/restarted along the way */ - handle = ext4_journal_start_sb(sb, EXT4_MAX_TRANS_DATA); - if (IS_ERR(handle)) - return PTR_ERR(handle); - - group = group_data[0].group; - for (i = 0; i < flex_gd->count; i++, group++) { - unsigned long gdblocks; - - gdblocks = ext4_bg_num_gdb(sb, group); - start = ext4_group_first_block_no(sb, group); - - /* Copy all of the GDT blocks into the backup in this group */ - for (j = 0, block = start + 1; j < gdblocks; j++, block++) { - struct buffer_head *gdb; - - ext4_debug("update backup group %#04llx\n", block); - err = extend_or_restart_transaction(handle, 1); - if (err) - goto out; - - gdb = sb_getblk(sb, block); - if (!gdb) { - err = -EIO; - goto out; - } - - err = ext4_journal_get_write_access(handle, gdb); - if (err) { - brelse(gdb); - goto out; - } - memcpy(gdb->b_data, sbi->s_group_desc[j]->b_data, - gdb->b_size); - set_buffer_uptodate(gdb); - - err = ext4_handle_dirty_metadata(handle, NULL, gdb); - if (unlikely(err)) { - brelse(gdb); - goto out; - } - brelse(gdb); - } - - /* Zero out all of the reserved backup group descriptor - * table blocks - */ - if (ext4_bg_has_super(sb, group)) { - err = sb_issue_zeroout(sb, gdblocks + start + 1, - reserved_gdb, GFP_NOFS); - if (err) - goto out; - } - - /* Initialize group tables of the grop @group */ - if (!(bg_flags[i] & EXT4_BG_INODE_ZEROED)) - goto handle_bb; - - /* Zero out all of the inode table blocks */ - block = group_data[i].inode_table; - ext4_debug("clear inode table blocks %#04llx -> %#04lx\n", - block, sbi->s_itb_per_group); - err = sb_issue_zeroout(sb, block, sbi->s_itb_per_group, - GFP_NOFS); - if (err) - goto out; - -handle_bb: - if (bg_flags[i] & EXT4_BG_BLOCK_UNINIT) - goto handle_ib; - - /* Initialize block bitmap of the @group */ - block = group_data[i].block_bitmap; - err = extend_or_restart_transaction(handle, 1); - if (err) - goto out; - - bh = bclean(handle, sb, block); - if (IS_ERR(bh)) { - err = PTR_ERR(bh); - goto out; - } - if (ext4_bg_has_super(sb, group)) { - ext4_debug("mark backup superblock %#04llx (+0)\n", - start); - ext4_set_bits(bh->b_data, 0, gdblocks + reserved_gdb + - 1); - } - ext4_mark_bitmap_end(group_data[i].blocks_count, - sb->s_blocksize * 8, bh->b_data); - err = ext4_handle_dirty_metadata(handle, NULL, bh); - if (err) - goto out; - brelse(bh); - -handle_ib: - if (bg_flags[i] & EXT4_BG_INODE_UNINIT) - continue; - - /* Initialize inode bitmap of the @group */ - block = group_data[i].inode_bitmap; - err = extend_or_restart_transaction(handle, 1); - if (err) - goto out; - /* Mark unused entries in inode bitmap used */ - bh = bclean(handle, sb, block); - if (IS_ERR(bh)) { - err = PTR_ERR(bh); - goto out; - } - - ext4_mark_bitmap_end(EXT4_INODES_PER_GROUP(sb), - sb->s_blocksize * 8, bh->b_data); - err = ext4_handle_dirty_metadata(handle, NULL, bh); - if (err) - goto out; - brelse(bh); - } - bh = NULL; - - /* Mark group tables in block bitmap */ - for (j = 0; j < GROUP_TABLE_COUNT; j++) { - count = group_table_count[j]; - start = (&group_data[0].block_bitmap)[j]; - block = start; - for (i = 1; i < flex_gd->count; i++) { - block += group_table_count[j]; - if (block == (&group_data[i].block_bitmap)[j]) { - count += group_table_count[j]; - continue; - } - err = set_flexbg_block_bitmap(sb, handle, - flex_gd, start, count); - if (err) - goto out; - count = group_table_count[j]; - start = group_data[i].block_bitmap; - block = start; - } - - if (count) { - err = set_flexbg_block_bitmap(sb, handle, - flex_gd, start, count); - if (err) - goto out; - } - } - -out: - brelse(bh); - err2 = ext4_journal_stop(handle); - if (err2 && !err) - err = err2; - - return err; -} - -/* - * Iterate through the groups which hold BACKUP superblock/GDT copies in an - * ext4 filesystem. The counters should be initialized to 1, 5, and 7 before - * calling this for the first time. In a sparse filesystem it will be the - * sequence of powers of 3, 5, and 7: 1, 3, 5, 7, 9, 25, 27, 49, 81, ... - * For a non-sparse filesystem it will be every group: 1, 2, 3, 4, ... - */ -static unsigned ext4_list_backups(struct super_block *sb, unsigned *three, - unsigned *five, unsigned *seven) -{ - unsigned *min = three; - int mult = 3; - unsigned ret; - - if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, - EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER)) { - ret = *min; - *min += 1; - return ret; - } - - if (*five < *min) { - min = five; - mult = 5; - } - if (*seven < *min) { - min = seven; - mult = 7; - } - - ret = *min; - *min *= mult; - - return ret; -} - -/* - * Check that all of the backup GDT blocks are held in the primary GDT block. - * It is assumed that they are stored in group order. Returns the number of - * groups in current filesystem that have BACKUPS, or -ve error code. - */ -static int verify_reserved_gdb(struct super_block *sb, - ext4_group_t end, - struct buffer_head *primary) -{ - const ext4_fsblk_t blk = primary->b_blocknr; - unsigned three = 1; - unsigned five = 5; - unsigned seven = 7; - unsigned grp; - __le32 *p = (__le32 *)primary->b_data; - int gdbackups = 0; - - while ((grp = ext4_list_backups(sb, &three, &five, &seven)) < end) { - if (le32_to_cpu(*p++) != - grp * EXT4_BLOCKS_PER_GROUP(sb) + blk){ - ext4_warning(sb, "reserved GDT %llu" - " missing grp %d (%llu)", - blk, grp, - grp * - (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) + - blk); - return -EINVAL; - } - if (++gdbackups > EXT4_ADDR_PER_BLOCK(sb)) - return -EFBIG; - } - - return gdbackups; -} - -/* - * Called when we need to bring a reserved group descriptor table block into - * use from the resize inode. The primary copy of the new GDT block currently - * is an indirect block (under the double indirect block in the resize inode). - * The new backup GDT blocks will be stored as leaf blocks in this indirect - * block, in group order. Even though we know all the block numbers we need, - * we check to ensure that the resize inode has actually reserved these blocks. - * - * Don't need to update the block bitmaps because the blocks are still in use. - * - * We get all of the error cases out of the way, so that we are sure to not - * fail once we start modifying the data on disk, because JBD has no rollback. - */ -static int add_new_gdb(handle_t *handle, struct inode *inode, - ext4_group_t group) -{ - struct super_block *sb = inode->i_sb; - struct ext4_super_block *es = EXT4_SB(sb)->s_es; - unsigned long gdb_num = group / EXT4_DESC_PER_BLOCK(sb); - ext4_fsblk_t gdblock = EXT4_SB(sb)->s_sbh->b_blocknr + 1 + gdb_num; - struct buffer_head **o_group_desc, **n_group_desc; - struct buffer_head *dind; - struct buffer_head *gdb_bh; - int gdbackups; - struct ext4_iloc iloc; - __le32 *data; - int err; - - if (test_opt(sb, DEBUG)) - printk(KERN_DEBUG - "EXT4-fs: ext4_add_new_gdb: adding group block %lu\n", - gdb_num); - - /* - * If we are not using the primary superblock/GDT copy don't resize, - * because the user tools have no way of handling this. Probably a - * bad time to do it anyways. - */ - if (EXT4_SB(sb)->s_sbh->b_blocknr != - le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block)) { - ext4_warning(sb, "won't resize using backup superblock at %llu", - (unsigned long long)EXT4_SB(sb)->s_sbh->b_blocknr); - return -EPERM; - } - - gdb_bh = sb_bread(sb, gdblock); - if (!gdb_bh) - return -EIO; - - gdbackups = verify_reserved_gdb(sb, group, gdb_bh); - if (gdbackups < 0) { - err = gdbackups; - goto exit_bh; - } - - data = EXT4_I(inode)->i_data + EXT4_DIND_BLOCK; - dind = sb_bread(sb, le32_to_cpu(*data)); - if (!dind) { - err = -EIO; - goto exit_bh; - } - - data = (__le32 *)dind->b_data; - if (le32_to_cpu(data[gdb_num % EXT4_ADDR_PER_BLOCK(sb)]) != gdblock) { - ext4_warning(sb, "new group %u GDT block %llu not reserved", - group, gdblock); - err = -EINVAL; - goto exit_dind; - } - - err = ext4_journal_get_write_access(handle, EXT4_SB(sb)->s_sbh); - if (unlikely(err)) - goto exit_dind; - - err = ext4_journal_get_write_access(handle, gdb_bh); - if (unlikely(err)) - goto exit_sbh; - - err = ext4_journal_get_write_access(handle, dind); - if (unlikely(err)) - ext4_std_error(sb, err); - - /* ext4_reserve_inode_write() gets a reference on the iloc */ - err = ext4_reserve_inode_write(handle, inode, &iloc); - if (unlikely(err)) - goto exit_dindj; - - n_group_desc = ext4_kvmalloc((gdb_num + 1) * - sizeof(struct buffer_head *), - GFP_NOFS); - if (!n_group_desc) { - err = -ENOMEM; - ext4_warning(sb, "not enough memory for %lu groups", - gdb_num + 1); - goto exit_inode; - } - - /* - * Finally, we have all of the possible failures behind us... - * - * Remove new GDT block from inode double-indirect block and clear out - * the new GDT block for use (which also "frees" the backup GDT blocks - * from the reserved inode). We don't need to change the bitmaps for - * these blocks, because they are marked as in-use from being in the - * reserved inode, and will become GDT blocks (primary and backup). - */ - data[gdb_num % EXT4_ADDR_PER_BLOCK(sb)] = 0; - err = ext4_handle_dirty_metadata(handle, NULL, dind); - if (unlikely(err)) { - ext4_std_error(sb, err); - goto exit_inode; - } - inode->i_blocks -= (gdbackups + 1) * sb->s_blocksize >> 9; - ext4_mark_iloc_dirty(handle, inode, &iloc); - memset(gdb_bh->b_data, 0, sb->s_blocksize); - err = ext4_handle_dirty_metadata(handle, NULL, gdb_bh); - if (unlikely(err)) { - ext4_std_error(sb, err); - goto exit_inode; - } - brelse(dind); - - o_group_desc = EXT4_SB(sb)->s_group_desc; - memcpy(n_group_desc, o_group_desc, - EXT4_SB(sb)->s_gdb_count * sizeof(struct buffer_head *)); - n_group_desc[gdb_num] = gdb_bh; - EXT4_SB(sb)->s_group_desc = n_group_desc; - EXT4_SB(sb)->s_gdb_count++; - ext4_kvfree(o_group_desc); - - le16_add_cpu(&es->s_reserved_gdt_blocks, -1); - err = ext4_handle_dirty_metadata(handle, NULL, EXT4_SB(sb)->s_sbh); - if (err) - ext4_std_error(sb, err); - - return err; - -exit_inode: - ext4_kvfree(n_group_desc); - /* ext4_handle_release_buffer(handle, iloc.bh); */ - brelse(iloc.bh); -exit_dindj: - /* ext4_handle_release_buffer(handle, dind); */ -exit_sbh: - /* ext4_handle_release_buffer(handle, EXT4_SB(sb)->s_sbh); */ -exit_dind: - brelse(dind); -exit_bh: - brelse(gdb_bh); - - ext4_debug("leaving with error %d\n", err); - return err; -} - -/* - * Called when we are adding a new group which has a backup copy of each of - * the GDT blocks (i.e. sparse group) and there are reserved GDT blocks. - * We need to add these reserved backup GDT blocks to the resize inode, so - * that they are kept for future resizing and not allocated to files. - * - * Each reserved backup GDT block will go into a different indirect block. - * The indirect blocks are actually the primary reserved GDT blocks, - * so we know in advance what their block numbers are. We only get the - * double-indirect block to verify it is pointing to the primary reserved - * GDT blocks so we don't overwrite a data block by accident. The reserved - * backup GDT blocks are stored in their reserved primary GDT block. - */ -static int reserve_backup_gdb(handle_t *handle, struct inode *inode, - ext4_group_t group) -{ - struct super_block *sb = inode->i_sb; - int reserved_gdb =le16_to_cpu(EXT4_SB(sb)->s_es->s_reserved_gdt_blocks); - struct buffer_head **primary; - struct buffer_head *dind; - struct ext4_iloc iloc; - ext4_fsblk_t blk; - __le32 *data, *end; - int gdbackups = 0; - int res, i; - int err; - - primary = kmalloc(reserved_gdb * sizeof(*primary), GFP_NOFS); - if (!primary) - return -ENOMEM; - - data = EXT4_I(inode)->i_data + EXT4_DIND_BLOCK; - dind = sb_bread(sb, le32_to_cpu(*data)); - if (!dind) { - err = -EIO; - goto exit_free; - } - - blk = EXT4_SB(sb)->s_sbh->b_blocknr + 1 + EXT4_SB(sb)->s_gdb_count; - data = (__le32 *)dind->b_data + (EXT4_SB(sb)->s_gdb_count % - EXT4_ADDR_PER_BLOCK(sb)); - end = (__le32 *)dind->b_data + EXT4_ADDR_PER_BLOCK(sb); - - /* Get each reserved primary GDT block and verify it holds backups */ - for (res = 0; res < reserved_gdb; res++, blk++) { - if (le32_to_cpu(*data) != blk) { - ext4_warning(sb, "reserved block %llu" - " not at offset %ld", - blk, - (long)(data - (__le32 *)dind->b_data)); - err = -EINVAL; - goto exit_bh; - } - primary[res] = sb_bread(sb, blk); - if (!primary[res]) { - err = -EIO; - goto exit_bh; - } - gdbackups = verify_reserved_gdb(sb, group, primary[res]); - if (gdbackups < 0) { - brelse(primary[res]); - err = gdbackups; - goto exit_bh; - } - if (++data >= end) - data = (__le32 *)dind->b_data; - } - - for (i = 0; i < reserved_gdb; i++) { - if ((err = ext4_journal_get_write_access(handle, primary[i]))) { - /* - int j; - for (j = 0; j < i; j++) - ext4_handle_release_buffer(handle, primary[j]); - */ - goto exit_bh; - } - } - - if ((err = ext4_reserve_inode_write(handle, inode, &iloc))) - goto exit_bh; - - /* - * Finally we can add each of the reserved backup GDT blocks from - * the new group to its reserved primary GDT block. - */ - blk = group * EXT4_BLOCKS_PER_GROUP(sb); - for (i = 0; i < reserved_gdb; i++) { - int err2; - data = (__le32 *)primary[i]->b_data; - /* printk("reserving backup %lu[%u] = %lu\n", - primary[i]->b_blocknr, gdbackups, - blk + primary[i]->b_blocknr); */ - data[gdbackups] = cpu_to_le32(blk + primary[i]->b_blocknr); - err2 = ext4_handle_dirty_metadata(handle, NULL, primary[i]); - if (!err) - err = err2; - } - inode->i_blocks += reserved_gdb * sb->s_blocksize >> 9; - ext4_mark_iloc_dirty(handle, inode, &iloc); - -exit_bh: - while (--res >= 0) - brelse(primary[res]); - brelse(dind); - -exit_free: - kfree(primary); - - return err; -} - -/* - * Update the backup copies of the ext4 metadata. These don't need to be part - * of the main resize transaction, because e2fsck will re-write them if there - * is a problem (basically only OOM will cause a problem). However, we - * _should_ update the backups if possible, in case the primary gets trashed - * for some reason and we need to run e2fsck from a backup superblock. The - * important part is that the new block and inode counts are in the backup - * superblocks, and the location of the new group metadata in the GDT backups. - * - * We do not need take the s_resize_lock for this, because these - * blocks are not otherwise touched by the filesystem code when it is - * mounted. We don't need to worry about last changing from - * sbi->s_groups_count, because the worst that can happen is that we - * do not copy the full number of backups at this time. The resize - * which changed s_groups_count will backup again. - */ -static void update_backups(struct super_block *sb, - int blk_off, char *data, int size) -{ - struct ext4_sb_info *sbi = EXT4_SB(sb); - const ext4_group_t last = sbi->s_groups_count; - const int bpg = EXT4_BLOCKS_PER_GROUP(sb); - unsigned three = 1; - unsigned five = 5; - unsigned seven = 7; - ext4_group_t group; - int rest = sb->s_blocksize - size; - handle_t *handle; - int err = 0, err2; - - handle = ext4_journal_start_sb(sb, EXT4_MAX_TRANS_DATA); - if (IS_ERR(handle)) { - group = 1; - err = PTR_ERR(handle); - goto exit_err; - } - - while ((group = ext4_list_backups(sb, &three, &five, &seven)) < last) { - struct buffer_head *bh; - - /* Out of journal space, and can't get more - abort - so sad */ - if (ext4_handle_valid(handle) && - handle->h_buffer_credits == 0 && - ext4_journal_extend(handle, EXT4_MAX_TRANS_DATA) && - (err = ext4_journal_restart(handle, EXT4_MAX_TRANS_DATA))) - break; - - bh = sb_getblk(sb, group * bpg + blk_off); - if (!bh) { - err = -EIO; - break; - } - ext4_debug("update metadata backup %#04lx\n", - (unsigned long)bh->b_blocknr); - if ((err = ext4_journal_get_write_access(handle, bh))) - break; - lock_buffer(bh); - memcpy(bh->b_data, data, size); - if (rest) - memset(bh->b_data + size, 0, rest); - set_buffer_uptodate(bh); - unlock_buffer(bh); - err = ext4_handle_dirty_metadata(handle, NULL, bh); - if (unlikely(err)) - ext4_std_error(sb, err); - brelse(bh); - } - if ((err2 = ext4_journal_stop(handle)) && !err) - err = err2; - - /* - * Ugh! Need to have e2fsck write the backup copies. It is too - * late to revert the resize, we shouldn't fail just because of - * the backup copies (they are only needed in case of corruption). - * - * However, if we got here we have a journal problem too, so we - * can't really start a transaction to mark the superblock. - * Chicken out and just set the flag on the hope it will be written - * to disk, and if not - we will simply wait until next fsck. - */ -exit_err: - if (err) { - ext4_warning(sb, "can't update backup for group %u (err %d), " - "forcing fsck on next reboot", group, err); - sbi->s_mount_state &= ~EXT4_VALID_FS; - sbi->s_es->s_state &= cpu_to_le16(~EXT4_VALID_FS); - mark_buffer_dirty(sbi->s_sbh); - } -} - -/* - * ext4_add_new_descs() adds @count group descriptor of groups - * starting at @group - * - * @handle: journal handle - * @sb: super block - * @group: the group no. of the first group desc to be added - * @resize_inode: the resize inode - * @count: number of group descriptors to be added - */ -static int ext4_add_new_descs(handle_t *handle, struct super_block *sb, - ext4_group_t group, struct inode *resize_inode, - ext4_group_t count) -{ - struct ext4_sb_info *sbi = EXT4_SB(sb); - struct ext4_super_block *es = sbi->s_es; - struct buffer_head *gdb_bh; - int i, gdb_off, gdb_num, err = 0; - - for (i = 0; i < count; i++, group++) { - int reserved_gdb = ext4_bg_has_super(sb, group) ? - le16_to_cpu(es->s_reserved_gdt_blocks) : 0; - - gdb_off = group % EXT4_DESC_PER_BLOCK(sb); - gdb_num = group / EXT4_DESC_PER_BLOCK(sb); - - /* - * We will only either add reserved group blocks to a backup group - * or remove reserved blocks for the first group in a new group block. - * Doing both would be mean more complex code, and sane people don't - * use non-sparse filesystems anymore. This is already checked above. - */ - if (gdb_off) { - gdb_bh = sbi->s_group_desc[gdb_num]; - err = ext4_journal_get_write_access(handle, gdb_bh); - - if (!err && reserved_gdb && ext4_bg_num_gdb(sb, group)) - err = reserve_backup_gdb(handle, resize_inode, group); - } else - err = add_new_gdb(handle, resize_inode, group); - if (err) - break; - } - return err; -} - -/* - * ext4_setup_new_descs() will set up the group descriptor descriptors of a flex bg - */ -static int ext4_setup_new_descs(handle_t *handle, struct super_block *sb, - struct ext4_new_flex_group_data *flex_gd) -{ - struct ext4_new_group_data *group_data = flex_gd->groups; - struct ext4_group_desc *gdp; - struct ext4_sb_info *sbi = EXT4_SB(sb); - struct buffer_head *gdb_bh; - ext4_group_t group; - __u16 *bg_flags = flex_gd->bg_flags; - int i, gdb_off, gdb_num, err = 0; - - - for (i = 0; i < flex_gd->count; i++, group_data++, bg_flags++) { - group = group_data->group; - - gdb_off = group % EXT4_DESC_PER_BLOCK(sb); - gdb_num = group / EXT4_DESC_PER_BLOCK(sb); - - /* - * get_write_access() has been called on gdb_bh by ext4_add_new_desc(). - */ - gdb_bh = sbi->s_group_desc[gdb_num]; - /* Update group descriptor block for new group */ - gdp = (struct ext4_group_desc *)((char *)gdb_bh->b_data + - gdb_off * EXT4_DESC_SIZE(sb)); - - memset(gdp, 0, EXT4_DESC_SIZE(sb)); - ext4_block_bitmap_set(sb, gdp, group_data->block_bitmap); - ext4_inode_bitmap_set(sb, gdp, group_data->inode_bitmap); - ext4_inode_table_set(sb, gdp, group_data->inode_table); - ext4_free_group_clusters_set(sb, gdp, - EXT4_B2C(sbi, group_data->free_blocks_count)); - ext4_free_inodes_set(sb, gdp, EXT4_INODES_PER_GROUP(sb)); - gdp->bg_flags = cpu_to_le16(*bg_flags); - gdp->bg_checksum = ext4_group_desc_csum(sbi, group, gdp); - - err = ext4_handle_dirty_metadata(handle, NULL, gdb_bh); - if (unlikely(err)) { - ext4_std_error(sb, err); - break; - } - - /* - * We can allocate memory for mb_alloc based on the new group - * descriptor - */ - err = ext4_mb_add_groupinfo(sb, group, gdp); - if (err) - break; - } - return err; -} - -/* - * ext4_update_super() updates the super block so that the newly added - * groups can be seen by the filesystem. - * - * @sb: super block - * @flex_gd: new added groups - */ -static void ext4_update_super(struct super_block *sb, - struct ext4_new_flex_group_data *flex_gd) -{ - ext4_fsblk_t blocks_count = 0; - ext4_fsblk_t free_blocks = 0; - ext4_fsblk_t reserved_blocks = 0; - struct ext4_new_group_data *group_data = flex_gd->groups; - struct ext4_sb_info *sbi = EXT4_SB(sb); - struct ext4_super_block *es = sbi->s_es; - int i; - - BUG_ON(flex_gd->count == 0 || group_data == NULL); - /* - * Make the new blocks and inodes valid next. We do this before - * increasing the group count so that once the group is enabled, - * all of its blocks and inodes are already valid. - * - * We always allocate group-by-group, then block-by-block or - * inode-by-inode within a group, so enabling these - * blocks/inodes before the group is live won't actually let us - * allocate the new space yet. - */ - for (i = 0; i < flex_gd->count; i++) { - blocks_count += group_data[i].blocks_count; - free_blocks += group_data[i].free_blocks_count; - } - - reserved_blocks = ext4_r_blocks_count(es) * 100; - do_div(reserved_blocks, ext4_blocks_count(es)); - reserved_blocks *= blocks_count; - do_div(reserved_blocks, 100); - - ext4_blocks_count_set(es, ext4_blocks_count(es) + blocks_count); - ext4_free_blocks_count_set(es, ext4_free_blocks_count(es) + free_blocks); - le32_add_cpu(&es->s_inodes_count, EXT4_INODES_PER_GROUP(sb) * - flex_gd->count); - le32_add_cpu(&es->s_free_inodes_count, EXT4_INODES_PER_GROUP(sb) * - flex_gd->count); - - /* - * We need to protect s_groups_count against other CPUs seeing - * inconsistent state in the superblock. - * - * The precise rules we use are: - * - * * Writers must perform a smp_wmb() after updating all - * dependent data and before modifying the groups count - * - * * Readers must perform an smp_rmb() after reading the groups - * count and before reading any dependent data. - * - * NB. These rules can be relaxed when checking the group count - * while freeing data, as we can only allocate from a block - * group after serialising against the group count, and we can - * only then free after serialising in turn against that - * allocation. - */ - smp_wmb(); - - /* Update the global fs size fields */ - sbi->s_groups_count += flex_gd->count; - - /* Update the reserved block counts only once the new group is - * active. */ - ext4_r_blocks_count_set(es, ext4_r_blocks_count(es) + - reserved_blocks); - - /* Update the free space counts */ - percpu_counter_add(&sbi->s_freeclusters_counter, - EXT4_B2C(sbi, free_blocks)); - percpu_counter_add(&sbi->s_freeinodes_counter, - EXT4_INODES_PER_GROUP(sb) * flex_gd->count); - - if (EXT4_HAS_INCOMPAT_FEATURE(sb, - EXT4_FEATURE_INCOMPAT_FLEX_BG) && - sbi->s_log_groups_per_flex) { - ext4_group_t flex_group; - flex_group = ext4_flex_group(sbi, group_data[0].group); - atomic_add(EXT4_B2C(sbi, free_blocks), - &sbi->s_flex_groups[flex_group].free_clusters); - atomic_add(EXT4_INODES_PER_GROUP(sb) * flex_gd->count, - &sbi->s_flex_groups[flex_group].free_inodes); - } - - if (test_opt(sb, DEBUG)) - printk(KERN_DEBUG "EXT4-fs: added group %u:" - "%llu blocks(%llu free %llu reserved)\n", flex_gd->count, - blocks_count, free_blocks, reserved_blocks); -} - -/* Add a flex group to an fs. Ensure we handle all possible error conditions - * _before_ we start modifying the filesystem, because we cannot abort the - * transaction and not have it write the data to disk. - */ -static int ext4_flex_group_add(struct super_block *sb, - struct inode *resize_inode, - struct ext4_new_flex_group_data *flex_gd) -{ - struct ext4_sb_info *sbi = EXT4_SB(sb); - struct ext4_super_block *es = sbi->s_es; - ext4_fsblk_t o_blocks_count; - ext4_grpblk_t last; - ext4_group_t group; - handle_t *handle; - unsigned reserved_gdb; - int err = 0, err2 = 0, credit; - - BUG_ON(!flex_gd->count || !flex_gd->groups || !flex_gd->bg_flags); - - reserved_gdb = le16_to_cpu(es->s_reserved_gdt_blocks); - o_blocks_count = ext4_blocks_count(es); - ext4_get_group_no_and_offset(sb, o_blocks_count, &group, &last); - BUG_ON(last); - - err = setup_new_flex_group_blocks(sb, flex_gd); - if (err) - goto exit; - /* - * We will always be modifying at least the superblock and GDT - * block. If we are adding a group past the last current GDT block, - * we will also modify the inode and the dindirect block. If we - * are adding a group with superblock/GDT backups we will also - * modify each of the reserved GDT dindirect blocks. - */ - credit = flex_gd->count * 4 + reserved_gdb; - handle = ext4_journal_start_sb(sb, credit); - if (IS_ERR(handle)) { - err = PTR_ERR(handle); - goto exit; - } - - err = ext4_journal_get_write_access(handle, sbi->s_sbh); - if (err) - goto exit_journal; - - group = flex_gd->groups[0].group; - BUG_ON(group != EXT4_SB(sb)->s_groups_count); - err = ext4_add_new_descs(handle, sb, group, - resize_inode, flex_gd->count); - if (err) - goto exit_journal; - - err = ext4_setup_new_descs(handle, sb, flex_gd); - if (err) - goto exit_journal; - - ext4_update_super(sb, flex_gd); - - err = ext4_handle_dirty_super(handle, sb); - -exit_journal: - err2 = ext4_journal_stop(handle); - if (!err) - err = err2; - - if (!err) { - int i; - update_backups(sb, sbi->s_sbh->b_blocknr, (char *)es, - sizeof(struct ext4_super_block)); - for (i = 0; i < flex_gd->count; i++, group++) { - struct buffer_head *gdb_bh; - int gdb_num; - gdb_num = group / EXT4_BLOCKS_PER_GROUP(sb); - gdb_bh = sbi->s_group_desc[gdb_num]; - update_backups(sb, gdb_bh->b_blocknr, gdb_bh->b_data, - gdb_bh->b_size); - } - } -exit: - return err; -} - -static int ext4_setup_next_flex_gd(struct super_block *sb, - struct ext4_new_flex_group_data *flex_gd, - ext4_fsblk_t n_blocks_count, - unsigned long flexbg_size) -{ - struct ext4_super_block *es = EXT4_SB(sb)->s_es; - struct ext4_new_group_data *group_data = flex_gd->groups; - ext4_fsblk_t o_blocks_count; - ext4_group_t n_group; - ext4_group_t group; - ext4_group_t last_group; - ext4_grpblk_t last; - ext4_grpblk_t blocks_per_group; - unsigned long i; - - blocks_per_group = EXT4_BLOCKS_PER_GROUP(sb); - - o_blocks_count = ext4_blocks_count(es); - - if (o_blocks_count == n_blocks_count) - return 0; - - ext4_get_group_no_and_offset(sb, o_blocks_count, &group, &last); - BUG_ON(last); - ext4_get_group_no_and_offset(sb, n_blocks_count - 1, &n_group, &last); - - last_group = group | (flexbg_size - 1); - if (last_group > n_group) - last_group = n_group; - - flex_gd->count = last_group - group + 1; - - for (i = 0; i < flex_gd->count; i++) { - int overhead; - - group_data[i].group = group + i; - group_data[i].blocks_count = blocks_per_group; - overhead = ext4_bg_has_super(sb, group + i) ? - (1 + ext4_bg_num_gdb(sb, group + i) + - le16_to_cpu(es->s_reserved_gdt_blocks)) : 0; - group_data[i].free_blocks_count = blocks_per_group - overhead; - if (EXT4_HAS_RO_COMPAT_FEATURE(sb, - EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) - flex_gd->bg_flags[i] = EXT4_BG_BLOCK_UNINIT | - EXT4_BG_INODE_UNINIT; - else - flex_gd->bg_flags[i] = EXT4_BG_INODE_ZEROED; - } - - if (last_group == n_group && - EXT4_HAS_RO_COMPAT_FEATURE(sb, - EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) - /* We need to initialize block bitmap of last group. */ - flex_gd->bg_flags[i - 1] &= ~EXT4_BG_BLOCK_UNINIT; - - if ((last_group == n_group) && (last != blocks_per_group - 1)) { - group_data[i - 1].blocks_count = last + 1; - group_data[i - 1].free_blocks_count -= blocks_per_group- - last - 1; - } - - return 1; -} - -/* Add group descriptor data to an existing or new group descriptor block. - * Ensure we handle all possible error conditions _before_ we start modifying - * the filesystem, because we cannot abort the transaction and not have it - * write the data to disk. - * - * If we are on a GDT block boundary, we need to get the reserved GDT block. - * Otherwise, we may need to add backup GDT blocks for a sparse group. - * - * We only need to hold the superblock lock while we are actually adding - * in the new group's counts to the superblock. Prior to that we have - * not really "added" the group at all. We re-check that we are still - * adding in the last group in case things have changed since verifying. - */ -int ext4_group_add(struct super_block *sb, struct ext4_new_group_data *input) -{ - struct ext4_new_flex_group_data flex_gd; - struct ext4_sb_info *sbi = EXT4_SB(sb); - struct ext4_super_block *es = sbi->s_es; - int reserved_gdb = ext4_bg_has_super(sb, input->group) ? - le16_to_cpu(es->s_reserved_gdt_blocks) : 0; - struct inode *inode = NULL; - int gdb_off, gdb_num; - int err; - __u16 bg_flags = 0; - - gdb_num = input->group / EXT4_DESC_PER_BLOCK(sb); - gdb_off = input->group % EXT4_DESC_PER_BLOCK(sb); - - if (gdb_off == 0 && !EXT4_HAS_RO_COMPAT_FEATURE(sb, - EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER)) { - ext4_warning(sb, "Can't resize non-sparse filesystem further"); - return -EPERM; - } - - if (ext4_blocks_count(es) + input->blocks_count < - ext4_blocks_count(es)) { - ext4_warning(sb, "blocks_count overflow"); - return -EINVAL; - } - - if (le32_to_cpu(es->s_inodes_count) + EXT4_INODES_PER_GROUP(sb) < - le32_to_cpu(es->s_inodes_count)) { - ext4_warning(sb, "inodes_count overflow"); - return -EINVAL; - } - - if (reserved_gdb || gdb_off == 0) { - if (!EXT4_HAS_COMPAT_FEATURE(sb, - EXT4_FEATURE_COMPAT_RESIZE_INODE) - || !le16_to_cpu(es->s_reserved_gdt_blocks)) { - ext4_warning(sb, - "No reserved GDT blocks, can't resize"); - return -EPERM; - } - inode = ext4_iget(sb, EXT4_RESIZE_INO); - if (IS_ERR(inode)) { - ext4_warning(sb, "Error opening resize inode"); - return PTR_ERR(inode); - } - } - - - err = verify_group_input(sb, input); - if (err) - goto out; - - flex_gd.count = 1; - flex_gd.groups = input; - flex_gd.bg_flags = &bg_flags; - err = ext4_flex_group_add(sb, inode, &flex_gd); -out: - iput(inode); - return err; -} /* ext4_group_add */ - -/* - * extend a group without checking assuming that checking has been done. - */ -static int ext4_group_extend_no_check(struct super_block *sb, - ext4_fsblk_t o_blocks_count, ext4_grpblk_t add) -{ - struct ext4_super_block *es = EXT4_SB(sb)->s_es; - handle_t *handle; - int err = 0, err2; - - /* We will update the superblock, one block bitmap, and - * one group descriptor via ext4_group_add_blocks(). - */ - handle = ext4_journal_start_sb(sb, 3); - if (IS_ERR(handle)) { - err = PTR_ERR(handle); - ext4_warning(sb, "error %d on journal start", err); - return err; - } - - err = ext4_journal_get_write_access(handle, EXT4_SB(sb)->s_sbh); - if (err) { - ext4_warning(sb, "error %d on journal write access", err); - goto errout; - } - - ext4_blocks_count_set(es, o_blocks_count + add); - ext4_free_blocks_count_set(es, ext4_free_blocks_count(es) + add); - ext4_debug("freeing blocks %llu through %llu\n", o_blocks_count, - o_blocks_count + add); - /* We add the blocks to the bitmap and set the group need init bit */ - err = ext4_group_add_blocks(handle, sb, o_blocks_count, add); - if (err) - goto errout; - ext4_handle_dirty_super(handle, sb); - ext4_debug("freed blocks %llu through %llu\n", o_blocks_count, - o_blocks_count + add); -errout: - err2 = ext4_journal_stop(handle); - if (err2 && !err) - err = err2; - - if (!err) { - if (test_opt(sb, DEBUG)) - printk(KERN_DEBUG "EXT4-fs: extended group to %llu " - "blocks\n", ext4_blocks_count(es)); - update_backups(sb, EXT4_SB(sb)->s_sbh->b_blocknr, (char *)es, - sizeof(struct ext4_super_block)); - } - return err; -} - -/* - * Extend the filesystem to the new number of blocks specified. This entry - * point is only used to extend the current filesystem to the end of the last - * existing group. It can be accessed via ioctl, or by "remount,resize=<size>" - * for emergencies (because it has no dependencies on reserved blocks). - * - * If we _really_ wanted, we could use default values to call ext4_group_add() - * allow the "remount" trick to work for arbitrary resizing, assuming enough - * GDT blocks are reserved to grow to the desired size. - */ -int ext4_group_extend(struct super_block *sb, struct ext4_super_block *es, - ext4_fsblk_t n_blocks_count) -{ - ext4_fsblk_t o_blocks_count; - ext4_grpblk_t last; - ext4_grpblk_t add; - struct buffer_head *bh; - int err; - ext4_group_t group; - - o_blocks_count = ext4_blocks_count(es); - - if (test_opt(sb, DEBUG)) - ext4_msg(sb, KERN_DEBUG, - "extending last group from %llu to %llu blocks", - o_blocks_count, n_blocks_count); - - if (n_blocks_count == 0 || n_blocks_count == o_blocks_count) - return 0; - - if (n_blocks_count > (sector_t)(~0ULL) >> (sb->s_blocksize_bits - 9)) { - ext4_msg(sb, KERN_ERR, - "filesystem too large to resize to %llu blocks safely", - n_blocks_count); - if (sizeof(sector_t) < 8) - ext4_warning(sb, "CONFIG_LBDAF not enabled"); - return -EINVAL; - } - - if (n_blocks_count < o_blocks_count) { - ext4_warning(sb, "can't shrink FS - resize aborted"); - return -EINVAL; - } - - /* Handle the remaining blocks in the last group only. */ - ext4_get_group_no_and_offset(sb, o_blocks_count, &group, &last); - - if (last == 0) { - ext4_warning(sb, "need to use ext2online to resize further"); - return -EPERM; - } - - add = EXT4_BLOCKS_PER_GROUP(sb) - last; - - if (o_blocks_count + add < o_blocks_count) { - ext4_warning(sb, "blocks_count overflow"); - return -EINVAL; - } - - if (o_blocks_count + add > n_blocks_count) - add = n_blocks_count - o_blocks_count; - - if (o_blocks_count + add < n_blocks_count) - ext4_warning(sb, "will only finish group (%llu blocks, %u new)", - o_blocks_count + add, add); - - /* See if the device is actually as big as what was requested */ - bh = sb_bread(sb, o_blocks_count + add - 1); - if (!bh) { - ext4_warning(sb, "can't read last block, resize aborted"); - return -ENOSPC; - } - brelse(bh); - - err = ext4_group_extend_no_check(sb, o_blocks_count, add); - return err; -} /* ext4_group_extend */ - -/* - * ext4_resize_fs() resizes a fs to new size specified by @n_blocks_count - * - * @sb: super block of the fs to be resized - * @n_blocks_count: the number of blocks resides in the resized fs - */ -int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count) -{ - struct ext4_new_flex_group_data *flex_gd = NULL; - struct ext4_sb_info *sbi = EXT4_SB(sb); - struct ext4_super_block *es = sbi->s_es; - struct buffer_head *bh; - struct inode *resize_inode; - ext4_fsblk_t o_blocks_count; - ext4_group_t o_group; - ext4_group_t n_group; - ext4_grpblk_t offset, add; - unsigned long n_desc_blocks; - unsigned long o_desc_blocks; - unsigned long desc_blocks; - int err = 0, flexbg_size = 1; - - o_blocks_count = ext4_blocks_count(es); - - if (test_opt(sb, DEBUG)) - ext4_msg(sb, KERN_DEBUG, "resizing filesystem from %llu " - "to %llu blocks", o_blocks_count, n_blocks_count); - - if (n_blocks_count < o_blocks_count) { - /* On-line shrinking not supported */ - ext4_warning(sb, "can't shrink FS - resize aborted"); - return -EINVAL; - } - - if (n_blocks_count == o_blocks_count) - /* Nothing need to do */ - return 0; - - ext4_get_group_no_and_offset(sb, n_blocks_count - 1, &n_group, &offset); - ext4_get_group_no_and_offset(sb, o_blocks_count - 1, &o_group, &offset); - - n_desc_blocks = (n_group + EXT4_DESC_PER_BLOCK(sb)) / - EXT4_DESC_PER_BLOCK(sb); - o_desc_blocks = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) / - EXT4_DESC_PER_BLOCK(sb); - desc_blocks = n_desc_blocks - o_desc_blocks; - - if (desc_blocks && - (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_RESIZE_INODE) || - le16_to_cpu(es->s_reserved_gdt_blocks) < desc_blocks)) { - ext4_warning(sb, "No reserved GDT blocks, can't resize"); - return -EPERM; - } - - resize_inode = ext4_iget(sb, EXT4_RESIZE_INO); - if (IS_ERR(resize_inode)) { - ext4_warning(sb, "Error opening resize inode"); - return PTR_ERR(resize_inode); - } - - /* See if the device is actually as big as what was requested */ - bh = sb_bread(sb, n_blocks_count - 1); - if (!bh) { - ext4_warning(sb, "can't read last block, resize aborted"); - return -ENOSPC; - } - brelse(bh); - - /* extend the last group */ - if (n_group == o_group) - add = n_blocks_count - o_blocks_count; - else - add = EXT4_BLOCKS_PER_GROUP(sb) - (offset + 1); - if (add > 0) { - err = ext4_group_extend_no_check(sb, o_blocks_count, add); - if (err) - goto out; - } - - if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG) && - es->s_log_groups_per_flex) - flexbg_size = 1 << es->s_log_groups_per_flex; - - o_blocks_count = ext4_blocks_count(es); - if (o_blocks_count == n_blocks_count) - goto out; - - flex_gd = alloc_flex_gd(flexbg_size); - if (flex_gd == NULL) { - err = -ENOMEM; - goto out; - } - - /* Add flex groups. Note that a regular group is a - * flex group with 1 group. - */ - while (ext4_setup_next_flex_gd(sb, flex_gd, n_blocks_count, - flexbg_size)) { - ext4_alloc_group_tables(sb, flex_gd, flexbg_size); - err = ext4_flex_group_add(sb, resize_inode, flex_gd); - if (unlikely(err)) - break; - } - -out: - if (flex_gd) - free_flex_gd(flex_gd); - - iput(resize_inode); - if (test_opt(sb, DEBUG)) - ext4_msg(sb, KERN_DEBUG, "resized filesystem from %llu " - "upto %llu blocks", o_blocks_count, n_blocks_count); - return err; -} |