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725 lines
18 KiB
725 lines
18 KiB
// SPDX-License-Identifier: GPL-2.0-only |
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/* |
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* vfsv0 quota IO operations on file |
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*/ |
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|
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#include <linux/errno.h> |
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#include <linux/fs.h> |
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#include <linux/mount.h> |
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#include <linux/dqblk_v2.h> |
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#include <linux/kernel.h> |
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#include <linux/init.h> |
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#include <linux/module.h> |
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#include <linux/slab.h> |
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#include <linux/quotaops.h> |
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#include <asm/byteorder.h> |
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#include "quota_tree.h" |
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MODULE_AUTHOR("Jan Kara"); |
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MODULE_DESCRIPTION("Quota trie support"); |
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MODULE_LICENSE("GPL"); |
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#define __QUOTA_QT_PARANOIA |
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static int __get_index(struct qtree_mem_dqinfo *info, qid_t id, int depth) |
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{ |
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unsigned int epb = info->dqi_usable_bs >> 2; |
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depth = info->dqi_qtree_depth - depth - 1; |
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while (depth--) |
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id /= epb; |
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return id % epb; |
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} |
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static int get_index(struct qtree_mem_dqinfo *info, struct kqid qid, int depth) |
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{ |
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qid_t id = from_kqid(&init_user_ns, qid); |
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return __get_index(info, id, depth); |
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} |
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/* Number of entries in one blocks */ |
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static int qtree_dqstr_in_blk(struct qtree_mem_dqinfo *info) |
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{ |
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return (info->dqi_usable_bs - sizeof(struct qt_disk_dqdbheader)) |
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/ info->dqi_entry_size; |
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} |
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static ssize_t read_blk(struct qtree_mem_dqinfo *info, uint blk, char *buf) |
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{ |
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struct super_block *sb = info->dqi_sb; |
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|
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memset(buf, 0, info->dqi_usable_bs); |
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return sb->s_op->quota_read(sb, info->dqi_type, buf, |
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info->dqi_usable_bs, (loff_t)blk << info->dqi_blocksize_bits); |
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} |
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static ssize_t write_blk(struct qtree_mem_dqinfo *info, uint blk, char *buf) |
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{ |
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struct super_block *sb = info->dqi_sb; |
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ssize_t ret; |
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ret = sb->s_op->quota_write(sb, info->dqi_type, buf, |
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info->dqi_usable_bs, (loff_t)blk << info->dqi_blocksize_bits); |
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if (ret != info->dqi_usable_bs) { |
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quota_error(sb, "dquota write failed"); |
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if (ret >= 0) |
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ret = -EIO; |
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} |
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return ret; |
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} |
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/* Remove empty block from list and return it */ |
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static int get_free_dqblk(struct qtree_mem_dqinfo *info) |
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{ |
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char *buf = kmalloc(info->dqi_usable_bs, GFP_NOFS); |
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struct qt_disk_dqdbheader *dh = (struct qt_disk_dqdbheader *)buf; |
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int ret, blk; |
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if (!buf) |
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return -ENOMEM; |
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if (info->dqi_free_blk) { |
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blk = info->dqi_free_blk; |
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ret = read_blk(info, blk, buf); |
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if (ret < 0) |
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goto out_buf; |
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info->dqi_free_blk = le32_to_cpu(dh->dqdh_next_free); |
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} |
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else { |
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memset(buf, 0, info->dqi_usable_bs); |
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/* Assure block allocation... */ |
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ret = write_blk(info, info->dqi_blocks, buf); |
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if (ret < 0) |
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goto out_buf; |
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blk = info->dqi_blocks++; |
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} |
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mark_info_dirty(info->dqi_sb, info->dqi_type); |
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ret = blk; |
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out_buf: |
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kfree(buf); |
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return ret; |
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} |
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/* Insert empty block to the list */ |
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static int put_free_dqblk(struct qtree_mem_dqinfo *info, char *buf, uint blk) |
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{ |
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struct qt_disk_dqdbheader *dh = (struct qt_disk_dqdbheader *)buf; |
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int err; |
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dh->dqdh_next_free = cpu_to_le32(info->dqi_free_blk); |
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dh->dqdh_prev_free = cpu_to_le32(0); |
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dh->dqdh_entries = cpu_to_le16(0); |
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err = write_blk(info, blk, buf); |
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if (err < 0) |
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return err; |
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info->dqi_free_blk = blk; |
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mark_info_dirty(info->dqi_sb, info->dqi_type); |
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return 0; |
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} |
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/* Remove given block from the list of blocks with free entries */ |
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static int remove_free_dqentry(struct qtree_mem_dqinfo *info, char *buf, |
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uint blk) |
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{ |
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char *tmpbuf = kmalloc(info->dqi_usable_bs, GFP_NOFS); |
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struct qt_disk_dqdbheader *dh = (struct qt_disk_dqdbheader *)buf; |
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uint nextblk = le32_to_cpu(dh->dqdh_next_free); |
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uint prevblk = le32_to_cpu(dh->dqdh_prev_free); |
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int err; |
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if (!tmpbuf) |
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return -ENOMEM; |
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if (nextblk) { |
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err = read_blk(info, nextblk, tmpbuf); |
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if (err < 0) |
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goto out_buf; |
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((struct qt_disk_dqdbheader *)tmpbuf)->dqdh_prev_free = |
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dh->dqdh_prev_free; |
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err = write_blk(info, nextblk, tmpbuf); |
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if (err < 0) |
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goto out_buf; |
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} |
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if (prevblk) { |
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err = read_blk(info, prevblk, tmpbuf); |
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if (err < 0) |
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goto out_buf; |
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((struct qt_disk_dqdbheader *)tmpbuf)->dqdh_next_free = |
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dh->dqdh_next_free; |
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err = write_blk(info, prevblk, tmpbuf); |
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if (err < 0) |
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goto out_buf; |
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} else { |
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info->dqi_free_entry = nextblk; |
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mark_info_dirty(info->dqi_sb, info->dqi_type); |
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} |
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kfree(tmpbuf); |
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dh->dqdh_next_free = dh->dqdh_prev_free = cpu_to_le32(0); |
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/* No matter whether write succeeds block is out of list */ |
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if (write_blk(info, blk, buf) < 0) |
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quota_error(info->dqi_sb, "Can't write block (%u) " |
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"with free entries", blk); |
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return 0; |
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out_buf: |
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kfree(tmpbuf); |
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return err; |
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} |
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/* Insert given block to the beginning of list with free entries */ |
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static int insert_free_dqentry(struct qtree_mem_dqinfo *info, char *buf, |
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uint blk) |
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{ |
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char *tmpbuf = kmalloc(info->dqi_usable_bs, GFP_NOFS); |
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struct qt_disk_dqdbheader *dh = (struct qt_disk_dqdbheader *)buf; |
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int err; |
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if (!tmpbuf) |
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return -ENOMEM; |
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dh->dqdh_next_free = cpu_to_le32(info->dqi_free_entry); |
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dh->dqdh_prev_free = cpu_to_le32(0); |
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err = write_blk(info, blk, buf); |
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if (err < 0) |
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goto out_buf; |
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if (info->dqi_free_entry) { |
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err = read_blk(info, info->dqi_free_entry, tmpbuf); |
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if (err < 0) |
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goto out_buf; |
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((struct qt_disk_dqdbheader *)tmpbuf)->dqdh_prev_free = |
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cpu_to_le32(blk); |
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err = write_blk(info, info->dqi_free_entry, tmpbuf); |
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if (err < 0) |
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goto out_buf; |
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} |
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kfree(tmpbuf); |
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info->dqi_free_entry = blk; |
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mark_info_dirty(info->dqi_sb, info->dqi_type); |
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return 0; |
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out_buf: |
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kfree(tmpbuf); |
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return err; |
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} |
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/* Is the entry in the block free? */ |
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int qtree_entry_unused(struct qtree_mem_dqinfo *info, char *disk) |
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{ |
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int i; |
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for (i = 0; i < info->dqi_entry_size; i++) |
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if (disk[i]) |
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return 0; |
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return 1; |
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} |
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EXPORT_SYMBOL(qtree_entry_unused); |
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/* Find space for dquot */ |
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static uint find_free_dqentry(struct qtree_mem_dqinfo *info, |
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struct dquot *dquot, int *err) |
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{ |
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uint blk, i; |
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struct qt_disk_dqdbheader *dh; |
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char *buf = kmalloc(info->dqi_usable_bs, GFP_NOFS); |
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char *ddquot; |
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*err = 0; |
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if (!buf) { |
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*err = -ENOMEM; |
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return 0; |
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} |
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dh = (struct qt_disk_dqdbheader *)buf; |
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if (info->dqi_free_entry) { |
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blk = info->dqi_free_entry; |
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*err = read_blk(info, blk, buf); |
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if (*err < 0) |
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goto out_buf; |
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} else { |
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blk = get_free_dqblk(info); |
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if ((int)blk < 0) { |
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*err = blk; |
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kfree(buf); |
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return 0; |
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} |
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memset(buf, 0, info->dqi_usable_bs); |
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/* This is enough as the block is already zeroed and the entry |
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* list is empty... */ |
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info->dqi_free_entry = blk; |
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mark_info_dirty(dquot->dq_sb, dquot->dq_id.type); |
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} |
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/* Block will be full? */ |
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if (le16_to_cpu(dh->dqdh_entries) + 1 >= qtree_dqstr_in_blk(info)) { |
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*err = remove_free_dqentry(info, buf, blk); |
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if (*err < 0) { |
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quota_error(dquot->dq_sb, "Can't remove block (%u) " |
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"from entry free list", blk); |
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goto out_buf; |
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} |
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} |
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le16_add_cpu(&dh->dqdh_entries, 1); |
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/* Find free structure in block */ |
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ddquot = buf + sizeof(struct qt_disk_dqdbheader); |
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for (i = 0; i < qtree_dqstr_in_blk(info); i++) { |
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if (qtree_entry_unused(info, ddquot)) |
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break; |
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ddquot += info->dqi_entry_size; |
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} |
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#ifdef __QUOTA_QT_PARANOIA |
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if (i == qtree_dqstr_in_blk(info)) { |
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quota_error(dquot->dq_sb, "Data block full but it shouldn't"); |
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*err = -EIO; |
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goto out_buf; |
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} |
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#endif |
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*err = write_blk(info, blk, buf); |
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if (*err < 0) { |
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quota_error(dquot->dq_sb, "Can't write quota data block %u", |
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blk); |
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goto out_buf; |
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} |
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dquot->dq_off = ((loff_t)blk << info->dqi_blocksize_bits) + |
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sizeof(struct qt_disk_dqdbheader) + |
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i * info->dqi_entry_size; |
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kfree(buf); |
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return blk; |
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out_buf: |
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kfree(buf); |
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return 0; |
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} |
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/* Insert reference to structure into the trie */ |
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static int do_insert_tree(struct qtree_mem_dqinfo *info, struct dquot *dquot, |
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uint *treeblk, int depth) |
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{ |
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char *buf = kmalloc(info->dqi_usable_bs, GFP_NOFS); |
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int ret = 0, newson = 0, newact = 0; |
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__le32 *ref; |
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uint newblk; |
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if (!buf) |
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return -ENOMEM; |
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if (!*treeblk) { |
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ret = get_free_dqblk(info); |
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if (ret < 0) |
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goto out_buf; |
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*treeblk = ret; |
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memset(buf, 0, info->dqi_usable_bs); |
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newact = 1; |
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} else { |
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ret = read_blk(info, *treeblk, buf); |
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if (ret < 0) { |
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quota_error(dquot->dq_sb, "Can't read tree quota " |
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"block %u", *treeblk); |
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goto out_buf; |
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} |
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} |
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ref = (__le32 *)buf; |
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newblk = le32_to_cpu(ref[get_index(info, dquot->dq_id, depth)]); |
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if (!newblk) |
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newson = 1; |
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if (depth == info->dqi_qtree_depth - 1) { |
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#ifdef __QUOTA_QT_PARANOIA |
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if (newblk) { |
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quota_error(dquot->dq_sb, "Inserting already present " |
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"quota entry (block %u)", |
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le32_to_cpu(ref[get_index(info, |
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dquot->dq_id, depth)])); |
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ret = -EIO; |
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goto out_buf; |
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} |
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#endif |
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newblk = find_free_dqentry(info, dquot, &ret); |
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} else { |
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ret = do_insert_tree(info, dquot, &newblk, depth+1); |
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} |
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if (newson && ret >= 0) { |
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ref[get_index(info, dquot->dq_id, depth)] = |
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cpu_to_le32(newblk); |
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ret = write_blk(info, *treeblk, buf); |
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} else if (newact && ret < 0) { |
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put_free_dqblk(info, buf, *treeblk); |
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} |
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out_buf: |
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kfree(buf); |
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return ret; |
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} |
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/* Wrapper for inserting quota structure into tree */ |
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static inline int dq_insert_tree(struct qtree_mem_dqinfo *info, |
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struct dquot *dquot) |
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{ |
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int tmp = QT_TREEOFF; |
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|
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#ifdef __QUOTA_QT_PARANOIA |
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if (info->dqi_blocks <= QT_TREEOFF) { |
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quota_error(dquot->dq_sb, "Quota tree root isn't allocated!"); |
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return -EIO; |
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} |
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#endif |
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return do_insert_tree(info, dquot, &tmp, 0); |
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} |
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/* |
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* We don't have to be afraid of deadlocks as we never have quotas on quota |
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* files... |
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*/ |
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int qtree_write_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot) |
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{ |
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int type = dquot->dq_id.type; |
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struct super_block *sb = dquot->dq_sb; |
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ssize_t ret; |
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char *ddquot = kmalloc(info->dqi_entry_size, GFP_NOFS); |
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|
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if (!ddquot) |
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return -ENOMEM; |
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/* dq_off is guarded by dqio_sem */ |
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if (!dquot->dq_off) { |
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ret = dq_insert_tree(info, dquot); |
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if (ret < 0) { |
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quota_error(sb, "Error %zd occurred while creating " |
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"quota", ret); |
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kfree(ddquot); |
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return ret; |
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} |
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} |
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spin_lock(&dquot->dq_dqb_lock); |
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info->dqi_ops->mem2disk_dqblk(ddquot, dquot); |
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spin_unlock(&dquot->dq_dqb_lock); |
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ret = sb->s_op->quota_write(sb, type, ddquot, info->dqi_entry_size, |
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dquot->dq_off); |
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if (ret != info->dqi_entry_size) { |
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quota_error(sb, "dquota write failed"); |
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if (ret >= 0) |
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ret = -ENOSPC; |
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} else { |
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ret = 0; |
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} |
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dqstats_inc(DQST_WRITES); |
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kfree(ddquot); |
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return ret; |
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} |
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EXPORT_SYMBOL(qtree_write_dquot); |
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/* Free dquot entry in data block */ |
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static int free_dqentry(struct qtree_mem_dqinfo *info, struct dquot *dquot, |
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uint blk) |
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{ |
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struct qt_disk_dqdbheader *dh; |
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char *buf = kmalloc(info->dqi_usable_bs, GFP_NOFS); |
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int ret = 0; |
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if (!buf) |
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return -ENOMEM; |
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if (dquot->dq_off >> info->dqi_blocksize_bits != blk) { |
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quota_error(dquot->dq_sb, "Quota structure has offset to " |
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"other block (%u) than it should (%u)", blk, |
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(uint)(dquot->dq_off >> info->dqi_blocksize_bits)); |
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goto out_buf; |
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} |
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ret = read_blk(info, blk, buf); |
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if (ret < 0) { |
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quota_error(dquot->dq_sb, "Can't read quota data block %u", |
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blk); |
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goto out_buf; |
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} |
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dh = (struct qt_disk_dqdbheader *)buf; |
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le16_add_cpu(&dh->dqdh_entries, -1); |
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if (!le16_to_cpu(dh->dqdh_entries)) { /* Block got free? */ |
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ret = remove_free_dqentry(info, buf, blk); |
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if (ret >= 0) |
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ret = put_free_dqblk(info, buf, blk); |
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if (ret < 0) { |
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quota_error(dquot->dq_sb, "Can't move quota data block " |
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"(%u) to free list", blk); |
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goto out_buf; |
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} |
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} else { |
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memset(buf + |
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(dquot->dq_off & ((1 << info->dqi_blocksize_bits) - 1)), |
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0, info->dqi_entry_size); |
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if (le16_to_cpu(dh->dqdh_entries) == |
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qtree_dqstr_in_blk(info) - 1) { |
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/* Insert will write block itself */ |
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ret = insert_free_dqentry(info, buf, blk); |
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if (ret < 0) { |
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quota_error(dquot->dq_sb, "Can't insert quota " |
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"data block (%u) to free entry list", blk); |
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goto out_buf; |
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} |
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} else { |
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ret = write_blk(info, blk, buf); |
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if (ret < 0) { |
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quota_error(dquot->dq_sb, "Can't write quota " |
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"data block %u", blk); |
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goto out_buf; |
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} |
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} |
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} |
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dquot->dq_off = 0; /* Quota is now unattached */ |
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out_buf: |
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kfree(buf); |
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return ret; |
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} |
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/* Remove reference to dquot from tree */ |
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static int remove_tree(struct qtree_mem_dqinfo *info, struct dquot *dquot, |
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uint *blk, int depth) |
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{ |
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char *buf = kmalloc(info->dqi_usable_bs, GFP_NOFS); |
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int ret = 0; |
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uint newblk; |
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__le32 *ref = (__le32 *)buf; |
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|
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if (!buf) |
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return -ENOMEM; |
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ret = read_blk(info, *blk, buf); |
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if (ret < 0) { |
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quota_error(dquot->dq_sb, "Can't read quota data block %u", |
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*blk); |
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goto out_buf; |
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} |
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newblk = le32_to_cpu(ref[get_index(info, dquot->dq_id, depth)]); |
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if (depth == info->dqi_qtree_depth - 1) { |
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ret = free_dqentry(info, dquot, newblk); |
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newblk = 0; |
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} else { |
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ret = remove_tree(info, dquot, &newblk, depth+1); |
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} |
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if (ret >= 0 && !newblk) { |
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int i; |
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ref[get_index(info, dquot->dq_id, depth)] = cpu_to_le32(0); |
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/* Block got empty? */ |
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for (i = 0; i < (info->dqi_usable_bs >> 2) && !ref[i]; i++) |
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; |
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/* Don't put the root block into the free block list */ |
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if (i == (info->dqi_usable_bs >> 2) |
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&& *blk != QT_TREEOFF) { |
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put_free_dqblk(info, buf, *blk); |
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*blk = 0; |
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} else { |
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ret = write_blk(info, *blk, buf); |
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if (ret < 0) |
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quota_error(dquot->dq_sb, |
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"Can't write quota tree block %u", |
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*blk); |
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} |
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} |
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out_buf: |
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kfree(buf); |
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return ret; |
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} |
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|
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/* Delete dquot from tree */ |
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int qtree_delete_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot) |
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{ |
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uint tmp = QT_TREEOFF; |
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|
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if (!dquot->dq_off) /* Even not allocated? */ |
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return 0; |
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return remove_tree(info, dquot, &tmp, 0); |
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} |
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EXPORT_SYMBOL(qtree_delete_dquot); |
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|
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/* Find entry in block */ |
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static loff_t find_block_dqentry(struct qtree_mem_dqinfo *info, |
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struct dquot *dquot, uint blk) |
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{ |
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char *buf = kmalloc(info->dqi_usable_bs, GFP_NOFS); |
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loff_t ret = 0; |
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int i; |
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char *ddquot; |
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|
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if (!buf) |
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return -ENOMEM; |
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ret = read_blk(info, blk, buf); |
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if (ret < 0) { |
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quota_error(dquot->dq_sb, "Can't read quota tree " |
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"block %u", blk); |
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goto out_buf; |
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} |
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ddquot = buf + sizeof(struct qt_disk_dqdbheader); |
|
for (i = 0; i < qtree_dqstr_in_blk(info); i++) { |
|
if (info->dqi_ops->is_id(ddquot, dquot)) |
|
break; |
|
ddquot += info->dqi_entry_size; |
|
} |
|
if (i == qtree_dqstr_in_blk(info)) { |
|
quota_error(dquot->dq_sb, |
|
"Quota for id %u referenced but not present", |
|
from_kqid(&init_user_ns, dquot->dq_id)); |
|
ret = -EIO; |
|
goto out_buf; |
|
} else { |
|
ret = ((loff_t)blk << info->dqi_blocksize_bits) + sizeof(struct |
|
qt_disk_dqdbheader) + i * info->dqi_entry_size; |
|
} |
|
out_buf: |
|
kfree(buf); |
|
return ret; |
|
} |
|
|
|
/* Find entry for given id in the tree */ |
|
static loff_t find_tree_dqentry(struct qtree_mem_dqinfo *info, |
|
struct dquot *dquot, uint blk, int depth) |
|
{ |
|
char *buf = kmalloc(info->dqi_usable_bs, GFP_NOFS); |
|
loff_t ret = 0; |
|
__le32 *ref = (__le32 *)buf; |
|
|
|
if (!buf) |
|
return -ENOMEM; |
|
ret = read_blk(info, blk, buf); |
|
if (ret < 0) { |
|
quota_error(dquot->dq_sb, "Can't read quota tree block %u", |
|
blk); |
|
goto out_buf; |
|
} |
|
ret = 0; |
|
blk = le32_to_cpu(ref[get_index(info, dquot->dq_id, depth)]); |
|
if (!blk) /* No reference? */ |
|
goto out_buf; |
|
if (depth < info->dqi_qtree_depth - 1) |
|
ret = find_tree_dqentry(info, dquot, blk, depth+1); |
|
else |
|
ret = find_block_dqentry(info, dquot, blk); |
|
out_buf: |
|
kfree(buf); |
|
return ret; |
|
} |
|
|
|
/* Find entry for given id in the tree - wrapper function */ |
|
static inline loff_t find_dqentry(struct qtree_mem_dqinfo *info, |
|
struct dquot *dquot) |
|
{ |
|
return find_tree_dqentry(info, dquot, QT_TREEOFF, 0); |
|
} |
|
|
|
int qtree_read_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot) |
|
{ |
|
int type = dquot->dq_id.type; |
|
struct super_block *sb = dquot->dq_sb; |
|
loff_t offset; |
|
char *ddquot; |
|
int ret = 0; |
|
|
|
#ifdef __QUOTA_QT_PARANOIA |
|
/* Invalidated quota? */ |
|
if (!sb_dqopt(dquot->dq_sb)->files[type]) { |
|
quota_error(sb, "Quota invalidated while reading!"); |
|
return -EIO; |
|
} |
|
#endif |
|
/* Do we know offset of the dquot entry in the quota file? */ |
|
if (!dquot->dq_off) { |
|
offset = find_dqentry(info, dquot); |
|
if (offset <= 0) { /* Entry not present? */ |
|
if (offset < 0) |
|
quota_error(sb,"Can't read quota structure " |
|
"for id %u", |
|
from_kqid(&init_user_ns, |
|
dquot->dq_id)); |
|
dquot->dq_off = 0; |
|
set_bit(DQ_FAKE_B, &dquot->dq_flags); |
|
memset(&dquot->dq_dqb, 0, sizeof(struct mem_dqblk)); |
|
ret = offset; |
|
goto out; |
|
} |
|
dquot->dq_off = offset; |
|
} |
|
ddquot = kmalloc(info->dqi_entry_size, GFP_NOFS); |
|
if (!ddquot) |
|
return -ENOMEM; |
|
ret = sb->s_op->quota_read(sb, type, ddquot, info->dqi_entry_size, |
|
dquot->dq_off); |
|
if (ret != info->dqi_entry_size) { |
|
if (ret >= 0) |
|
ret = -EIO; |
|
quota_error(sb, "Error while reading quota structure for id %u", |
|
from_kqid(&init_user_ns, dquot->dq_id)); |
|
set_bit(DQ_FAKE_B, &dquot->dq_flags); |
|
memset(&dquot->dq_dqb, 0, sizeof(struct mem_dqblk)); |
|
kfree(ddquot); |
|
goto out; |
|
} |
|
spin_lock(&dquot->dq_dqb_lock); |
|
info->dqi_ops->disk2mem_dqblk(dquot, ddquot); |
|
if (!dquot->dq_dqb.dqb_bhardlimit && |
|
!dquot->dq_dqb.dqb_bsoftlimit && |
|
!dquot->dq_dqb.dqb_ihardlimit && |
|
!dquot->dq_dqb.dqb_isoftlimit) |
|
set_bit(DQ_FAKE_B, &dquot->dq_flags); |
|
spin_unlock(&dquot->dq_dqb_lock); |
|
kfree(ddquot); |
|
out: |
|
dqstats_inc(DQST_READS); |
|
return ret; |
|
} |
|
EXPORT_SYMBOL(qtree_read_dquot); |
|
|
|
/* Check whether dquot should not be deleted. We know we are |
|
* the only one operating on dquot (thanks to dq_lock) */ |
|
int qtree_release_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot) |
|
{ |
|
if (test_bit(DQ_FAKE_B, &dquot->dq_flags) && |
|
!(dquot->dq_dqb.dqb_curinodes | dquot->dq_dqb.dqb_curspace)) |
|
return qtree_delete_dquot(info, dquot); |
|
return 0; |
|
} |
|
EXPORT_SYMBOL(qtree_release_dquot); |
|
|
|
static int find_next_id(struct qtree_mem_dqinfo *info, qid_t *id, |
|
unsigned int blk, int depth) |
|
{ |
|
char *buf = kmalloc(info->dqi_usable_bs, GFP_NOFS); |
|
__le32 *ref = (__le32 *)buf; |
|
ssize_t ret; |
|
unsigned int epb = info->dqi_usable_bs >> 2; |
|
unsigned int level_inc = 1; |
|
int i; |
|
|
|
if (!buf) |
|
return -ENOMEM; |
|
|
|
for (i = depth; i < info->dqi_qtree_depth - 1; i++) |
|
level_inc *= epb; |
|
|
|
ret = read_blk(info, blk, buf); |
|
if (ret < 0) { |
|
quota_error(info->dqi_sb, |
|
"Can't read quota tree block %u", blk); |
|
goto out_buf; |
|
} |
|
for (i = __get_index(info, *id, depth); i < epb; i++) { |
|
if (ref[i] == cpu_to_le32(0)) { |
|
*id += level_inc; |
|
continue; |
|
} |
|
if (depth == info->dqi_qtree_depth - 1) { |
|
ret = 0; |
|
goto out_buf; |
|
} |
|
ret = find_next_id(info, id, le32_to_cpu(ref[i]), depth + 1); |
|
if (ret != -ENOENT) |
|
break; |
|
} |
|
if (i == epb) { |
|
ret = -ENOENT; |
|
goto out_buf; |
|
} |
|
out_buf: |
|
kfree(buf); |
|
return ret; |
|
} |
|
|
|
int qtree_get_next_id(struct qtree_mem_dqinfo *info, struct kqid *qid) |
|
{ |
|
qid_t id = from_kqid(&init_user_ns, *qid); |
|
int ret; |
|
|
|
ret = find_next_id(info, &id, QT_TREEOFF, 0); |
|
if (ret < 0) |
|
return ret; |
|
*qid = make_kqid(&init_user_ns, qid->type, id); |
|
return 0; |
|
} |
|
EXPORT_SYMBOL(qtree_get_next_id);
|
|
|