v4.19.13 snapshot.
diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c
new file mode 100644
index 0000000..2addcb8
--- /dev/null
+++ b/fs/ext4/ialloc.c
@@ -0,0 +1,1445 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * linux/fs/ext4/ialloc.c
+ *
+ * Copyright (C) 1992, 1993, 1994, 1995
+ * Remy Card (card@masi.ibp.fr)
+ * Laboratoire MASI - Institut Blaise Pascal
+ * Universite Pierre et Marie Curie (Paris VI)
+ *
+ * BSD ufs-inspired inode and directory allocation by
+ * Stephen Tweedie (sct@redhat.com), 1993
+ * Big-endian to little-endian byte-swapping/bitmaps by
+ * David S. Miller (davem@caip.rutgers.edu), 1995
+ */
+
+#include <linux/time.h>
+#include <linux/fs.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/quotaops.h>
+#include <linux/buffer_head.h>
+#include <linux/random.h>
+#include <linux/bitops.h>
+#include <linux/blkdev.h>
+#include <linux/cred.h>
+
+#include <asm/byteorder.h>
+
+#include "ext4.h"
+#include "ext4_jbd2.h"
+#include "xattr.h"
+#include "acl.h"
+
+#include <trace/events/ext4.h>
+
+/*
+ * ialloc.c contains the inodes allocation and deallocation routines
+ */
+
+/*
+ * The free inodes are managed by bitmaps. A file system contains several
+ * blocks groups. Each group contains 1 bitmap block for blocks, 1 bitmap
+ * block for inodes, N blocks for the inode table and data blocks.
+ *
+ * The file system contains group descriptors which are located after the
+ * super block. Each descriptor contains the number of the bitmap block and
+ * the free blocks count in the block.
+ */
+
+/*
+ * To avoid calling the atomic setbit hundreds or thousands of times, we only
+ * need to use it within a single byte (to ensure we get endianness right).
+ * We can use memset for the rest of the bitmap as there are no other users.
+ */
+void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap)
+{
+ int i;
+
+ if (start_bit >= end_bit)
+ return;
+
+ ext4_debug("mark end bits +%d through +%d used\n", start_bit, end_bit);
+ for (i = start_bit; i < ((start_bit + 7) & ~7UL); i++)
+ ext4_set_bit(i, bitmap);
+ if (i < end_bit)
+ memset(bitmap + (i >> 3), 0xff, (end_bit - i) >> 3);
+}
+
+void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate)
+{
+ if (uptodate) {
+ set_buffer_uptodate(bh);
+ set_bitmap_uptodate(bh);
+ }
+ unlock_buffer(bh);
+ put_bh(bh);
+}
+
+static int ext4_validate_inode_bitmap(struct super_block *sb,
+ struct ext4_group_desc *desc,
+ ext4_group_t block_group,
+ struct buffer_head *bh)
+{
+ ext4_fsblk_t blk;
+ struct ext4_group_info *grp = ext4_get_group_info(sb, block_group);
+
+ if (buffer_verified(bh))
+ return 0;
+ if (EXT4_MB_GRP_IBITMAP_CORRUPT(grp))
+ return -EFSCORRUPTED;
+
+ ext4_lock_group(sb, block_group);
+ if (buffer_verified(bh))
+ goto verified;
+ blk = ext4_inode_bitmap(sb, desc);
+ if (!ext4_inode_bitmap_csum_verify(sb, block_group, desc, bh,
+ EXT4_INODES_PER_GROUP(sb) / 8)) {
+ ext4_unlock_group(sb, block_group);
+ ext4_error(sb, "Corrupt inode bitmap - block_group = %u, "
+ "inode_bitmap = %llu", block_group, blk);
+ ext4_mark_group_bitmap_corrupted(sb, block_group,
+ EXT4_GROUP_INFO_IBITMAP_CORRUPT);
+ return -EFSBADCRC;
+ }
+ set_buffer_verified(bh);
+verified:
+ ext4_unlock_group(sb, block_group);
+ return 0;
+}
+
+/*
+ * Read the inode allocation bitmap for a given block_group, reading
+ * into the specified slot in the superblock's bitmap cache.
+ *
+ * Return buffer_head of bitmap on success or NULL.
+ */
+static struct buffer_head *
+ext4_read_inode_bitmap(struct super_block *sb, ext4_group_t block_group)
+{
+ struct ext4_group_desc *desc;
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+ struct buffer_head *bh = NULL;
+ ext4_fsblk_t bitmap_blk;
+ int err;
+
+ desc = ext4_get_group_desc(sb, block_group, NULL);
+ if (!desc)
+ return ERR_PTR(-EFSCORRUPTED);
+
+ bitmap_blk = ext4_inode_bitmap(sb, desc);
+ if ((bitmap_blk <= le32_to_cpu(sbi->s_es->s_first_data_block)) ||
+ (bitmap_blk >= ext4_blocks_count(sbi->s_es))) {
+ ext4_error(sb, "Invalid inode bitmap blk %llu in "
+ "block_group %u", bitmap_blk, block_group);
+ ext4_mark_group_bitmap_corrupted(sb, block_group,
+ EXT4_GROUP_INFO_IBITMAP_CORRUPT);
+ return ERR_PTR(-EFSCORRUPTED);
+ }
+ bh = sb_getblk(sb, bitmap_blk);
+ if (unlikely(!bh)) {
+ ext4_warning(sb, "Cannot read inode bitmap - "
+ "block_group = %u, inode_bitmap = %llu",
+ block_group, bitmap_blk);
+ return ERR_PTR(-ENOMEM);
+ }
+ if (bitmap_uptodate(bh))
+ goto verify;
+
+ lock_buffer(bh);
+ if (bitmap_uptodate(bh)) {
+ unlock_buffer(bh);
+ goto verify;
+ }
+
+ ext4_lock_group(sb, block_group);
+ if (ext4_has_group_desc_csum(sb) &&
+ (desc->bg_flags & cpu_to_le16(EXT4_BG_INODE_UNINIT))) {
+ if (block_group == 0) {
+ ext4_unlock_group(sb, block_group);
+ unlock_buffer(bh);
+ ext4_error(sb, "Inode bitmap for bg 0 marked "
+ "uninitialized");
+ err = -EFSCORRUPTED;
+ goto out;
+ }
+ memset(bh->b_data, 0, (EXT4_INODES_PER_GROUP(sb) + 7) / 8);
+ ext4_mark_bitmap_end(EXT4_INODES_PER_GROUP(sb),
+ sb->s_blocksize * 8, bh->b_data);
+ set_bitmap_uptodate(bh);
+ set_buffer_uptodate(bh);
+ set_buffer_verified(bh);
+ ext4_unlock_group(sb, block_group);
+ unlock_buffer(bh);
+ return bh;
+ }
+ ext4_unlock_group(sb, block_group);
+
+ if (buffer_uptodate(bh)) {
+ /*
+ * if not uninit if bh is uptodate,
+ * bitmap is also uptodate
+ */
+ set_bitmap_uptodate(bh);
+ unlock_buffer(bh);
+ goto verify;
+ }
+ /*
+ * submit the buffer_head for reading
+ */
+ trace_ext4_load_inode_bitmap(sb, block_group);
+ bh->b_end_io = ext4_end_bitmap_read;
+ get_bh(bh);
+ submit_bh(REQ_OP_READ, REQ_META | REQ_PRIO, bh);
+ wait_on_buffer(bh);
+ if (!buffer_uptodate(bh)) {
+ put_bh(bh);
+ ext4_error(sb, "Cannot read inode bitmap - "
+ "block_group = %u, inode_bitmap = %llu",
+ block_group, bitmap_blk);
+ ext4_mark_group_bitmap_corrupted(sb, block_group,
+ EXT4_GROUP_INFO_IBITMAP_CORRUPT);
+ return ERR_PTR(-EIO);
+ }
+
+verify:
+ err = ext4_validate_inode_bitmap(sb, desc, block_group, bh);
+ if (err)
+ goto out;
+ return bh;
+out:
+ put_bh(bh);
+ return ERR_PTR(err);
+}
+
+/*
+ * NOTE! When we get the inode, we're the only people
+ * that have access to it, and as such there are no
+ * race conditions we have to worry about. The inode
+ * is not on the hash-lists, and it cannot be reached
+ * through the filesystem because the directory entry
+ * has been deleted earlier.
+ *
+ * HOWEVER: we must make sure that we get no aliases,
+ * which means that we have to call "clear_inode()"
+ * _before_ we mark the inode not in use in the inode
+ * bitmaps. Otherwise a newly created file might use
+ * the same inode number (not actually the same pointer
+ * though), and then we'd have two inodes sharing the
+ * same inode number and space on the harddisk.
+ */
+void ext4_free_inode(handle_t *handle, struct inode *inode)
+{
+ struct super_block *sb = inode->i_sb;
+ int is_directory;
+ unsigned long ino;
+ struct buffer_head *bitmap_bh = NULL;
+ struct buffer_head *bh2;
+ ext4_group_t block_group;
+ unsigned long bit;
+ struct ext4_group_desc *gdp;
+ struct ext4_super_block *es;
+ struct ext4_sb_info *sbi;
+ int fatal = 0, err, count, cleared;
+ struct ext4_group_info *grp;
+
+ if (!sb) {
+ printk(KERN_ERR "EXT4-fs: %s:%d: inode on "
+ "nonexistent device\n", __func__, __LINE__);
+ return;
+ }
+ if (atomic_read(&inode->i_count) > 1) {
+ ext4_msg(sb, KERN_ERR, "%s:%d: inode #%lu: count=%d",
+ __func__, __LINE__, inode->i_ino,
+ atomic_read(&inode->i_count));
+ return;
+ }
+ if (inode->i_nlink) {
+ ext4_msg(sb, KERN_ERR, "%s:%d: inode #%lu: nlink=%d\n",
+ __func__, __LINE__, inode->i_ino, inode->i_nlink);
+ return;
+ }
+ sbi = EXT4_SB(sb);
+
+ ino = inode->i_ino;
+ ext4_debug("freeing inode %lu\n", ino);
+ trace_ext4_free_inode(inode);
+
+ /*
+ * Note: we must free any quota before locking the superblock,
+ * as writing the quota to disk may need the lock as well.
+ */
+ dquot_initialize(inode);
+ dquot_free_inode(inode);
+ dquot_drop(inode);
+
+ is_directory = S_ISDIR(inode->i_mode);
+
+ /* Do this BEFORE marking the inode not in use or returning an error */
+ ext4_clear_inode(inode);
+
+ es = sbi->s_es;
+ if (ino < EXT4_FIRST_INO(sb) || ino > le32_to_cpu(es->s_inodes_count)) {
+ ext4_error(sb, "reserved or nonexistent inode %lu", ino);
+ goto error_return;
+ }
+ block_group = (ino - 1) / EXT4_INODES_PER_GROUP(sb);
+ bit = (ino - 1) % EXT4_INODES_PER_GROUP(sb);
+ bitmap_bh = ext4_read_inode_bitmap(sb, block_group);
+ /* Don't bother if the inode bitmap is corrupt. */
+ grp = ext4_get_group_info(sb, block_group);
+ if (IS_ERR(bitmap_bh)) {
+ fatal = PTR_ERR(bitmap_bh);
+ bitmap_bh = NULL;
+ goto error_return;
+ }
+ if (unlikely(EXT4_MB_GRP_IBITMAP_CORRUPT(grp))) {
+ fatal = -EFSCORRUPTED;
+ goto error_return;
+ }
+
+ BUFFER_TRACE(bitmap_bh, "get_write_access");
+ fatal = ext4_journal_get_write_access(handle, bitmap_bh);
+ if (fatal)
+ goto error_return;
+
+ fatal = -ESRCH;
+ gdp = ext4_get_group_desc(sb, block_group, &bh2);
+ if (gdp) {
+ BUFFER_TRACE(bh2, "get_write_access");
+ fatal = ext4_journal_get_write_access(handle, bh2);
+ }
+ ext4_lock_group(sb, block_group);
+ cleared = ext4_test_and_clear_bit(bit, bitmap_bh->b_data);
+ if (fatal || !cleared) {
+ ext4_unlock_group(sb, block_group);
+ goto out;
+ }
+
+ count = ext4_free_inodes_count(sb, gdp) + 1;
+ ext4_free_inodes_set(sb, gdp, count);
+ if (is_directory) {
+ count = ext4_used_dirs_count(sb, gdp) - 1;
+ ext4_used_dirs_set(sb, gdp, count);
+ percpu_counter_dec(&sbi->s_dirs_counter);
+ }
+ ext4_inode_bitmap_csum_set(sb, block_group, gdp, bitmap_bh,
+ EXT4_INODES_PER_GROUP(sb) / 8);
+ ext4_group_desc_csum_set(sb, block_group, gdp);
+ ext4_unlock_group(sb, block_group);
+
+ percpu_counter_inc(&sbi->s_freeinodes_counter);
+ if (sbi->s_log_groups_per_flex) {
+ ext4_group_t f = ext4_flex_group(sbi, block_group);
+
+ atomic_inc(&sbi->s_flex_groups[f].free_inodes);
+ if (is_directory)
+ atomic_dec(&sbi->s_flex_groups[f].used_dirs);
+ }
+ BUFFER_TRACE(bh2, "call ext4_handle_dirty_metadata");
+ fatal = ext4_handle_dirty_metadata(handle, NULL, bh2);
+out:
+ if (cleared) {
+ BUFFER_TRACE(bitmap_bh, "call ext4_handle_dirty_metadata");
+ err = ext4_handle_dirty_metadata(handle, NULL, bitmap_bh);
+ if (!fatal)
+ fatal = err;
+ } else {
+ ext4_error(sb, "bit already cleared for inode %lu", ino);
+ ext4_mark_group_bitmap_corrupted(sb, block_group,
+ EXT4_GROUP_INFO_IBITMAP_CORRUPT);
+ }
+
+error_return:
+ brelse(bitmap_bh);
+ ext4_std_error(sb, fatal);
+}
+
+struct orlov_stats {
+ __u64 free_clusters;
+ __u32 free_inodes;
+ __u32 used_dirs;
+};
+
+/*
+ * Helper function for Orlov's allocator; returns critical information
+ * for a particular block group or flex_bg. If flex_size is 1, then g
+ * is a block group number; otherwise it is flex_bg number.
+ */
+static void get_orlov_stats(struct super_block *sb, ext4_group_t g,
+ int flex_size, struct orlov_stats *stats)
+{
+ struct ext4_group_desc *desc;
+ struct flex_groups *flex_group = EXT4_SB(sb)->s_flex_groups;
+
+ if (flex_size > 1) {
+ stats->free_inodes = atomic_read(&flex_group[g].free_inodes);
+ stats->free_clusters = atomic64_read(&flex_group[g].free_clusters);
+ stats->used_dirs = atomic_read(&flex_group[g].used_dirs);
+ return;
+ }
+
+ desc = ext4_get_group_desc(sb, g, NULL);
+ if (desc) {
+ stats->free_inodes = ext4_free_inodes_count(sb, desc);
+ stats->free_clusters = ext4_free_group_clusters(sb, desc);
+ stats->used_dirs = ext4_used_dirs_count(sb, desc);
+ } else {
+ stats->free_inodes = 0;
+ stats->free_clusters = 0;
+ stats->used_dirs = 0;
+ }
+}
+
+/*
+ * Orlov's allocator for directories.
+ *
+ * We always try to spread first-level directories.
+ *
+ * If there are blockgroups with both free inodes and free blocks counts
+ * not worse than average we return one with smallest directory count.
+ * Otherwise we simply return a random group.
+ *
+ * For the rest rules look so:
+ *
+ * It's OK to put directory into a group unless
+ * it has too many directories already (max_dirs) or
+ * it has too few free inodes left (min_inodes) or
+ * it has too few free blocks left (min_blocks) or
+ * Parent's group is preferred, if it doesn't satisfy these
+ * conditions we search cyclically through the rest. If none
+ * of the groups look good we just look for a group with more
+ * free inodes than average (starting at parent's group).
+ */
+
+static int find_group_orlov(struct super_block *sb, struct inode *parent,
+ ext4_group_t *group, umode_t mode,
+ const struct qstr *qstr)
+{
+ ext4_group_t parent_group = EXT4_I(parent)->i_block_group;
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+ ext4_group_t real_ngroups = ext4_get_groups_count(sb);
+ int inodes_per_group = EXT4_INODES_PER_GROUP(sb);
+ unsigned int freei, avefreei, grp_free;
+ ext4_fsblk_t freeb, avefreec;
+ unsigned int ndirs;
+ int max_dirs, min_inodes;
+ ext4_grpblk_t min_clusters;
+ ext4_group_t i, grp, g, ngroups;
+ struct ext4_group_desc *desc;
+ struct orlov_stats stats;
+ int flex_size = ext4_flex_bg_size(sbi);
+ struct dx_hash_info hinfo;
+
+ ngroups = real_ngroups;
+ if (flex_size > 1) {
+ ngroups = (real_ngroups + flex_size - 1) >>
+ sbi->s_log_groups_per_flex;
+ parent_group >>= sbi->s_log_groups_per_flex;
+ }
+
+ freei = percpu_counter_read_positive(&sbi->s_freeinodes_counter);
+ avefreei = freei / ngroups;
+ freeb = EXT4_C2B(sbi,
+ percpu_counter_read_positive(&sbi->s_freeclusters_counter));
+ avefreec = freeb;
+ do_div(avefreec, ngroups);
+ ndirs = percpu_counter_read_positive(&sbi->s_dirs_counter);
+
+ if (S_ISDIR(mode) &&
+ ((parent == d_inode(sb->s_root)) ||
+ (ext4_test_inode_flag(parent, EXT4_INODE_TOPDIR)))) {
+ int best_ndir = inodes_per_group;
+ int ret = -1;
+
+ if (qstr) {
+ hinfo.hash_version = DX_HASH_HALF_MD4;
+ hinfo.seed = sbi->s_hash_seed;
+ ext4fs_dirhash(qstr->name, qstr->len, &hinfo);
+ grp = hinfo.hash;
+ } else
+ grp = prandom_u32();
+ parent_group = (unsigned)grp % ngroups;
+ for (i = 0; i < ngroups; i++) {
+ g = (parent_group + i) % ngroups;
+ get_orlov_stats(sb, g, flex_size, &stats);
+ if (!stats.free_inodes)
+ continue;
+ if (stats.used_dirs >= best_ndir)
+ continue;
+ if (stats.free_inodes < avefreei)
+ continue;
+ if (stats.free_clusters < avefreec)
+ continue;
+ grp = g;
+ ret = 0;
+ best_ndir = stats.used_dirs;
+ }
+ if (ret)
+ goto fallback;
+ found_flex_bg:
+ if (flex_size == 1) {
+ *group = grp;
+ return 0;
+ }
+
+ /*
+ * We pack inodes at the beginning of the flexgroup's
+ * inode tables. Block allocation decisions will do
+ * something similar, although regular files will
+ * start at 2nd block group of the flexgroup. See
+ * ext4_ext_find_goal() and ext4_find_near().
+ */
+ grp *= flex_size;
+ for (i = 0; i < flex_size; i++) {
+ if (grp+i >= real_ngroups)
+ break;
+ desc = ext4_get_group_desc(sb, grp+i, NULL);
+ if (desc && ext4_free_inodes_count(sb, desc)) {
+ *group = grp+i;
+ return 0;
+ }
+ }
+ goto fallback;
+ }
+
+ max_dirs = ndirs / ngroups + inodes_per_group / 16;
+ min_inodes = avefreei - inodes_per_group*flex_size / 4;
+ if (min_inodes < 1)
+ min_inodes = 1;
+ min_clusters = avefreec - EXT4_CLUSTERS_PER_GROUP(sb)*flex_size / 4;
+
+ /*
+ * Start looking in the flex group where we last allocated an
+ * inode for this parent directory
+ */
+ if (EXT4_I(parent)->i_last_alloc_group != ~0) {
+ parent_group = EXT4_I(parent)->i_last_alloc_group;
+ if (flex_size > 1)
+ parent_group >>= sbi->s_log_groups_per_flex;
+ }
+
+ for (i = 0; i < ngroups; i++) {
+ grp = (parent_group + i) % ngroups;
+ get_orlov_stats(sb, grp, flex_size, &stats);
+ if (stats.used_dirs >= max_dirs)
+ continue;
+ if (stats.free_inodes < min_inodes)
+ continue;
+ if (stats.free_clusters < min_clusters)
+ continue;
+ goto found_flex_bg;
+ }
+
+fallback:
+ ngroups = real_ngroups;
+ avefreei = freei / ngroups;
+fallback_retry:
+ parent_group = EXT4_I(parent)->i_block_group;
+ for (i = 0; i < ngroups; i++) {
+ grp = (parent_group + i) % ngroups;
+ desc = ext4_get_group_desc(sb, grp, NULL);
+ if (desc) {
+ grp_free = ext4_free_inodes_count(sb, desc);
+ if (grp_free && grp_free >= avefreei) {
+ *group = grp;
+ return 0;
+ }
+ }
+ }
+
+ if (avefreei) {
+ /*
+ * The free-inodes counter is approximate, and for really small
+ * filesystems the above test can fail to find any blockgroups
+ */
+ avefreei = 0;
+ goto fallback_retry;
+ }
+
+ return -1;
+}
+
+static int find_group_other(struct super_block *sb, struct inode *parent,
+ ext4_group_t *group, umode_t mode)
+{
+ ext4_group_t parent_group = EXT4_I(parent)->i_block_group;
+ ext4_group_t i, last, ngroups = ext4_get_groups_count(sb);
+ struct ext4_group_desc *desc;
+ int flex_size = ext4_flex_bg_size(EXT4_SB(sb));
+
+ /*
+ * Try to place the inode is the same flex group as its
+ * parent. If we can't find space, use the Orlov algorithm to
+ * find another flex group, and store that information in the
+ * parent directory's inode information so that use that flex
+ * group for future allocations.
+ */
+ if (flex_size > 1) {
+ int retry = 0;
+
+ try_again:
+ parent_group &= ~(flex_size-1);
+ last = parent_group + flex_size;
+ if (last > ngroups)
+ last = ngroups;
+ for (i = parent_group; i < last; i++) {
+ desc = ext4_get_group_desc(sb, i, NULL);
+ if (desc && ext4_free_inodes_count(sb, desc)) {
+ *group = i;
+ return 0;
+ }
+ }
+ if (!retry && EXT4_I(parent)->i_last_alloc_group != ~0) {
+ retry = 1;
+ parent_group = EXT4_I(parent)->i_last_alloc_group;
+ goto try_again;
+ }
+ /*
+ * If this didn't work, use the Orlov search algorithm
+ * to find a new flex group; we pass in the mode to
+ * avoid the topdir algorithms.
+ */
+ *group = parent_group + flex_size;
+ if (*group > ngroups)
+ *group = 0;
+ return find_group_orlov(sb, parent, group, mode, NULL);
+ }
+
+ /*
+ * Try to place the inode in its parent directory
+ */
+ *group = parent_group;
+ desc = ext4_get_group_desc(sb, *group, NULL);
+ if (desc && ext4_free_inodes_count(sb, desc) &&
+ ext4_free_group_clusters(sb, desc))
+ return 0;
+
+ /*
+ * We're going to place this inode in a different blockgroup from its
+ * parent. We want to cause files in a common directory to all land in
+ * the same blockgroup. But we want files which are in a different
+ * directory which shares a blockgroup with our parent to land in a
+ * different blockgroup.
+ *
+ * So add our directory's i_ino into the starting point for the hash.
+ */
+ *group = (*group + parent->i_ino) % ngroups;
+
+ /*
+ * Use a quadratic hash to find a group with a free inode and some free
+ * blocks.
+ */
+ for (i = 1; i < ngroups; i <<= 1) {
+ *group += i;
+ if (*group >= ngroups)
+ *group -= ngroups;
+ desc = ext4_get_group_desc(sb, *group, NULL);
+ if (desc && ext4_free_inodes_count(sb, desc) &&
+ ext4_free_group_clusters(sb, desc))
+ return 0;
+ }
+
+ /*
+ * That failed: try linear search for a free inode, even if that group
+ * has no free blocks.
+ */
+ *group = parent_group;
+ for (i = 0; i < ngroups; i++) {
+ if (++*group >= ngroups)
+ *group = 0;
+ desc = ext4_get_group_desc(sb, *group, NULL);
+ if (desc && ext4_free_inodes_count(sb, desc))
+ return 0;
+ }
+
+ return -1;
+}
+
+/*
+ * In no journal mode, if an inode has recently been deleted, we want
+ * to avoid reusing it until we're reasonably sure the inode table
+ * block has been written back to disk. (Yes, these values are
+ * somewhat arbitrary...)
+ */
+#define RECENTCY_MIN 5
+#define RECENTCY_DIRTY 300
+
+static int recently_deleted(struct super_block *sb, ext4_group_t group, int ino)
+{
+ struct ext4_group_desc *gdp;
+ struct ext4_inode *raw_inode;
+ struct buffer_head *bh;
+ int inodes_per_block = EXT4_SB(sb)->s_inodes_per_block;
+ int offset, ret = 0;
+ int recentcy = RECENTCY_MIN;
+ u32 dtime, now;
+
+ gdp = ext4_get_group_desc(sb, group, NULL);
+ if (unlikely(!gdp))
+ return 0;
+
+ bh = sb_find_get_block(sb, ext4_inode_table(sb, gdp) +
+ (ino / inodes_per_block));
+ if (!bh || !buffer_uptodate(bh))
+ /*
+ * If the block is not in the buffer cache, then it
+ * must have been written out.
+ */
+ goto out;
+
+ offset = (ino % inodes_per_block) * EXT4_INODE_SIZE(sb);
+ raw_inode = (struct ext4_inode *) (bh->b_data + offset);
+
+ /* i_dtime is only 32 bits on disk, but we only care about relative
+ * times in the range of a few minutes (i.e. long enough to sync a
+ * recently-deleted inode to disk), so using the low 32 bits of the
+ * clock (a 68 year range) is enough, see time_before32() */
+ dtime = le32_to_cpu(raw_inode->i_dtime);
+ now = ktime_get_real_seconds();
+ if (buffer_dirty(bh))
+ recentcy += RECENTCY_DIRTY;
+
+ if (dtime && time_before32(dtime, now) &&
+ time_before32(now, dtime + recentcy))
+ ret = 1;
+out:
+ brelse(bh);
+ return ret;
+}
+
+static int find_inode_bit(struct super_block *sb, ext4_group_t group,
+ struct buffer_head *bitmap, unsigned long *ino)
+{
+next:
+ *ino = ext4_find_next_zero_bit((unsigned long *)
+ bitmap->b_data,
+ EXT4_INODES_PER_GROUP(sb), *ino);
+ if (*ino >= EXT4_INODES_PER_GROUP(sb))
+ return 0;
+
+ if ((EXT4_SB(sb)->s_journal == NULL) &&
+ recently_deleted(sb, group, *ino)) {
+ *ino = *ino + 1;
+ if (*ino < EXT4_INODES_PER_GROUP(sb))
+ goto next;
+ return 0;
+ }
+
+ return 1;
+}
+
+/*
+ * There are two policies for allocating an inode. If the new inode is
+ * a directory, then a forward search is made for a block group with both
+ * free space and a low directory-to-inode ratio; if that fails, then of
+ * the groups with above-average free space, that group with the fewest
+ * directories already is chosen.
+ *
+ * For other inodes, search forward from the parent directory's block
+ * group to find a free inode.
+ */
+struct inode *__ext4_new_inode(handle_t *handle, struct inode *dir,
+ umode_t mode, const struct qstr *qstr,
+ __u32 goal, uid_t *owner, __u32 i_flags,
+ int handle_type, unsigned int line_no,
+ int nblocks)
+{
+ struct super_block *sb;
+ struct buffer_head *inode_bitmap_bh = NULL;
+ struct buffer_head *group_desc_bh;
+ ext4_group_t ngroups, group = 0;
+ unsigned long ino = 0;
+ struct inode *inode;
+ struct ext4_group_desc *gdp = NULL;
+ struct ext4_inode_info *ei;
+ struct ext4_sb_info *sbi;
+ int ret2, err;
+ struct inode *ret;
+ ext4_group_t i;
+ ext4_group_t flex_group;
+ struct ext4_group_info *grp;
+ int encrypt = 0;
+
+ /* Cannot create files in a deleted directory */
+ if (!dir || !dir->i_nlink)
+ return ERR_PTR(-EPERM);
+
+ sb = dir->i_sb;
+ sbi = EXT4_SB(sb);
+
+ if (unlikely(ext4_forced_shutdown(sbi)))
+ return ERR_PTR(-EIO);
+
+ if ((ext4_encrypted_inode(dir) || DUMMY_ENCRYPTION_ENABLED(sbi)) &&
+ (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)) &&
+ !(i_flags & EXT4_EA_INODE_FL)) {
+ err = fscrypt_get_encryption_info(dir);
+ if (err)
+ return ERR_PTR(err);
+ if (!fscrypt_has_encryption_key(dir))
+ return ERR_PTR(-ENOKEY);
+ encrypt = 1;
+ }
+
+ if (!handle && sbi->s_journal && !(i_flags & EXT4_EA_INODE_FL)) {
+#ifdef CONFIG_EXT4_FS_POSIX_ACL
+ struct posix_acl *p = get_acl(dir, ACL_TYPE_DEFAULT);
+
+ if (IS_ERR(p))
+ return ERR_CAST(p);
+ if (p) {
+ int acl_size = p->a_count * sizeof(ext4_acl_entry);
+
+ nblocks += (S_ISDIR(mode) ? 2 : 1) *
+ __ext4_xattr_set_credits(sb, NULL /* inode */,
+ NULL /* block_bh */, acl_size,
+ true /* is_create */);
+ posix_acl_release(p);
+ }
+#endif
+
+#ifdef CONFIG_SECURITY
+ {
+ int num_security_xattrs = 1;
+
+#ifdef CONFIG_INTEGRITY
+ num_security_xattrs++;
+#endif
+ /*
+ * We assume that security xattrs are never
+ * more than 1k. In practice they are under
+ * 128 bytes.
+ */
+ nblocks += num_security_xattrs *
+ __ext4_xattr_set_credits(sb, NULL /* inode */,
+ NULL /* block_bh */, 1024,
+ true /* is_create */);
+ }
+#endif
+ if (encrypt)
+ nblocks += __ext4_xattr_set_credits(sb,
+ NULL /* inode */, NULL /* block_bh */,
+ FSCRYPT_SET_CONTEXT_MAX_SIZE,
+ true /* is_create */);
+ }
+
+ ngroups = ext4_get_groups_count(sb);
+ trace_ext4_request_inode(dir, mode);
+ inode = new_inode(sb);
+ if (!inode)
+ return ERR_PTR(-ENOMEM);
+ ei = EXT4_I(inode);
+
+ /*
+ * Initialize owners and quota early so that we don't have to account
+ * for quota initialization worst case in standard inode creating
+ * transaction
+ */
+ if (owner) {
+ inode->i_mode = mode;
+ i_uid_write(inode, owner[0]);
+ i_gid_write(inode, owner[1]);
+ } else if (test_opt(sb, GRPID)) {
+ inode->i_mode = mode;
+ inode->i_uid = current_fsuid();
+ inode->i_gid = dir->i_gid;
+ } else
+ inode_init_owner(inode, dir, mode);
+
+ if (ext4_has_feature_project(sb) &&
+ ext4_test_inode_flag(dir, EXT4_INODE_PROJINHERIT))
+ ei->i_projid = EXT4_I(dir)->i_projid;
+ else
+ ei->i_projid = make_kprojid(&init_user_ns, EXT4_DEF_PROJID);
+
+ err = dquot_initialize(inode);
+ if (err)
+ goto out;
+
+ if (!goal)
+ goal = sbi->s_inode_goal;
+
+ if (goal && goal <= le32_to_cpu(sbi->s_es->s_inodes_count)) {
+ group = (goal - 1) / EXT4_INODES_PER_GROUP(sb);
+ ino = (goal - 1) % EXT4_INODES_PER_GROUP(sb);
+ ret2 = 0;
+ goto got_group;
+ }
+
+ if (S_ISDIR(mode))
+ ret2 = find_group_orlov(sb, dir, &group, mode, qstr);
+ else
+ ret2 = find_group_other(sb, dir, &group, mode);
+
+got_group:
+ EXT4_I(dir)->i_last_alloc_group = group;
+ err = -ENOSPC;
+ if (ret2 == -1)
+ goto out;
+
+ /*
+ * Normally we will only go through one pass of this loop,
+ * unless we get unlucky and it turns out the group we selected
+ * had its last inode grabbed by someone else.
+ */
+ for (i = 0; i < ngroups; i++, ino = 0) {
+ err = -EIO;
+
+ gdp = ext4_get_group_desc(sb, group, &group_desc_bh);
+ if (!gdp)
+ goto out;
+
+ /*
+ * Check free inodes count before loading bitmap.
+ */
+ if (ext4_free_inodes_count(sb, gdp) == 0)
+ goto next_group;
+
+ grp = ext4_get_group_info(sb, group);
+ /* Skip groups with already-known suspicious inode tables */
+ if (EXT4_MB_GRP_IBITMAP_CORRUPT(grp))
+ goto next_group;
+
+ brelse(inode_bitmap_bh);
+ inode_bitmap_bh = ext4_read_inode_bitmap(sb, group);
+ /* Skip groups with suspicious inode tables */
+ if (EXT4_MB_GRP_IBITMAP_CORRUPT(grp) ||
+ IS_ERR(inode_bitmap_bh)) {
+ inode_bitmap_bh = NULL;
+ goto next_group;
+ }
+
+repeat_in_this_group:
+ ret2 = find_inode_bit(sb, group, inode_bitmap_bh, &ino);
+ if (!ret2)
+ goto next_group;
+
+ if (group == 0 && (ino + 1) < EXT4_FIRST_INO(sb)) {
+ ext4_error(sb, "reserved inode found cleared - "
+ "inode=%lu", ino + 1);
+ ext4_mark_group_bitmap_corrupted(sb, group,
+ EXT4_GROUP_INFO_IBITMAP_CORRUPT);
+ goto next_group;
+ }
+
+ if (!handle) {
+ BUG_ON(nblocks <= 0);
+ handle = __ext4_journal_start_sb(dir->i_sb, line_no,
+ handle_type, nblocks,
+ 0);
+ if (IS_ERR(handle)) {
+ err = PTR_ERR(handle);
+ ext4_std_error(sb, err);
+ goto out;
+ }
+ }
+ BUFFER_TRACE(inode_bitmap_bh, "get_write_access");
+ err = ext4_journal_get_write_access(handle, inode_bitmap_bh);
+ if (err) {
+ ext4_std_error(sb, err);
+ goto out;
+ }
+ ext4_lock_group(sb, group);
+ ret2 = ext4_test_and_set_bit(ino, inode_bitmap_bh->b_data);
+ if (ret2) {
+ /* Someone already took the bit. Repeat the search
+ * with lock held.
+ */
+ ret2 = find_inode_bit(sb, group, inode_bitmap_bh, &ino);
+ if (ret2) {
+ ext4_set_bit(ino, inode_bitmap_bh->b_data);
+ ret2 = 0;
+ } else {
+ ret2 = 1; /* we didn't grab the inode */
+ }
+ }
+ ext4_unlock_group(sb, group);
+ ino++; /* the inode bitmap is zero-based */
+ if (!ret2)
+ goto got; /* we grabbed the inode! */
+
+ if (ino < EXT4_INODES_PER_GROUP(sb))
+ goto repeat_in_this_group;
+next_group:
+ if (++group == ngroups)
+ group = 0;
+ }
+ err = -ENOSPC;
+ goto out;
+
+got:
+ BUFFER_TRACE(inode_bitmap_bh, "call ext4_handle_dirty_metadata");
+ err = ext4_handle_dirty_metadata(handle, NULL, inode_bitmap_bh);
+ if (err) {
+ ext4_std_error(sb, err);
+ goto out;
+ }
+
+ BUFFER_TRACE(group_desc_bh, "get_write_access");
+ err = ext4_journal_get_write_access(handle, group_desc_bh);
+ if (err) {
+ ext4_std_error(sb, err);
+ goto out;
+ }
+
+ /* We may have to initialize the block bitmap if it isn't already */
+ if (ext4_has_group_desc_csum(sb) &&
+ gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
+ struct buffer_head *block_bitmap_bh;
+
+ block_bitmap_bh = ext4_read_block_bitmap(sb, group);
+ if (IS_ERR(block_bitmap_bh)) {
+ err = PTR_ERR(block_bitmap_bh);
+ goto out;
+ }
+ BUFFER_TRACE(block_bitmap_bh, "get block bitmap access");
+ err = ext4_journal_get_write_access(handle, block_bitmap_bh);
+ if (err) {
+ brelse(block_bitmap_bh);
+ ext4_std_error(sb, err);
+ goto out;
+ }
+
+ BUFFER_TRACE(block_bitmap_bh, "dirty block bitmap");
+ err = ext4_handle_dirty_metadata(handle, NULL, block_bitmap_bh);
+
+ /* recheck and clear flag under lock if we still need to */
+ ext4_lock_group(sb, group);
+ if (ext4_has_group_desc_csum(sb) &&
+ (gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT))) {
+ gdp->bg_flags &= cpu_to_le16(~EXT4_BG_BLOCK_UNINIT);
+ ext4_free_group_clusters_set(sb, gdp,
+ ext4_free_clusters_after_init(sb, group, gdp));
+ ext4_block_bitmap_csum_set(sb, group, gdp,
+ block_bitmap_bh);
+ ext4_group_desc_csum_set(sb, group, gdp);
+ }
+ ext4_unlock_group(sb, group);
+ brelse(block_bitmap_bh);
+
+ if (err) {
+ ext4_std_error(sb, err);
+ goto out;
+ }
+ }
+
+ /* Update the relevant bg descriptor fields */
+ if (ext4_has_group_desc_csum(sb)) {
+ int free;
+ struct ext4_group_info *grp = ext4_get_group_info(sb, group);
+
+ down_read(&grp->alloc_sem); /* protect vs itable lazyinit */
+ ext4_lock_group(sb, group); /* while we modify the bg desc */
+ free = EXT4_INODES_PER_GROUP(sb) -
+ ext4_itable_unused_count(sb, gdp);
+ if (gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_UNINIT)) {
+ gdp->bg_flags &= cpu_to_le16(~EXT4_BG_INODE_UNINIT);
+ free = 0;
+ }
+ /*
+ * Check the relative inode number against the last used
+ * relative inode number in this group. if it is greater
+ * we need to update the bg_itable_unused count
+ */
+ if (ino > free)
+ ext4_itable_unused_set(sb, gdp,
+ (EXT4_INODES_PER_GROUP(sb) - ino));
+ up_read(&grp->alloc_sem);
+ } else {
+ ext4_lock_group(sb, group);
+ }
+
+ ext4_free_inodes_set(sb, gdp, ext4_free_inodes_count(sb, gdp) - 1);
+ if (S_ISDIR(mode)) {
+ ext4_used_dirs_set(sb, gdp, ext4_used_dirs_count(sb, gdp) + 1);
+ if (sbi->s_log_groups_per_flex) {
+ ext4_group_t f = ext4_flex_group(sbi, group);
+
+ atomic_inc(&sbi->s_flex_groups[f].used_dirs);
+ }
+ }
+ if (ext4_has_group_desc_csum(sb)) {
+ ext4_inode_bitmap_csum_set(sb, group, gdp, inode_bitmap_bh,
+ EXT4_INODES_PER_GROUP(sb) / 8);
+ ext4_group_desc_csum_set(sb, group, gdp);
+ }
+ ext4_unlock_group(sb, group);
+
+ BUFFER_TRACE(group_desc_bh, "call ext4_handle_dirty_metadata");
+ err = ext4_handle_dirty_metadata(handle, NULL, group_desc_bh);
+ if (err) {
+ ext4_std_error(sb, err);
+ goto out;
+ }
+
+ percpu_counter_dec(&sbi->s_freeinodes_counter);
+ if (S_ISDIR(mode))
+ percpu_counter_inc(&sbi->s_dirs_counter);
+
+ if (sbi->s_log_groups_per_flex) {
+ flex_group = ext4_flex_group(sbi, group);
+ atomic_dec(&sbi->s_flex_groups[flex_group].free_inodes);
+ }
+
+ inode->i_ino = ino + group * EXT4_INODES_PER_GROUP(sb);
+ /* This is the optimal IO size (for stat), not the fs block size */
+ inode->i_blocks = 0;
+ inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
+ ei->i_crtime = inode->i_mtime;
+
+ memset(ei->i_data, 0, sizeof(ei->i_data));
+ ei->i_dir_start_lookup = 0;
+ ei->i_disksize = 0;
+
+ /* Don't inherit extent flag from directory, amongst others. */
+ ei->i_flags =
+ ext4_mask_flags(mode, EXT4_I(dir)->i_flags & EXT4_FL_INHERITED);
+ ei->i_flags |= i_flags;
+ ei->i_file_acl = 0;
+ ei->i_dtime = 0;
+ ei->i_block_group = group;
+ ei->i_last_alloc_group = ~0;
+
+ ext4_set_inode_flags(inode);
+ if (IS_DIRSYNC(inode))
+ ext4_handle_sync(handle);
+ if (insert_inode_locked(inode) < 0) {
+ /*
+ * Likely a bitmap corruption causing inode to be allocated
+ * twice.
+ */
+ err = -EIO;
+ ext4_error(sb, "failed to insert inode %lu: doubly allocated?",
+ inode->i_ino);
+ ext4_mark_group_bitmap_corrupted(sb, group,
+ EXT4_GROUP_INFO_IBITMAP_CORRUPT);
+ goto out;
+ }
+ inode->i_generation = prandom_u32();
+
+ /* Precompute checksum seed for inode metadata */
+ if (ext4_has_metadata_csum(sb)) {
+ __u32 csum;
+ __le32 inum = cpu_to_le32(inode->i_ino);
+ __le32 gen = cpu_to_le32(inode->i_generation);
+ csum = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&inum,
+ sizeof(inum));
+ ei->i_csum_seed = ext4_chksum(sbi, csum, (__u8 *)&gen,
+ sizeof(gen));
+ }
+
+ ext4_clear_state_flags(ei); /* Only relevant on 32-bit archs */
+ ext4_set_inode_state(inode, EXT4_STATE_NEW);
+
+ ei->i_extra_isize = sbi->s_want_extra_isize;
+ ei->i_inline_off = 0;
+ if (ext4_has_feature_inline_data(sb))
+ ext4_set_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
+ ret = inode;
+ err = dquot_alloc_inode(inode);
+ if (err)
+ goto fail_drop;
+
+ /*
+ * Since the encryption xattr will always be unique, create it first so
+ * that it's less likely to end up in an external xattr block and
+ * prevent its deduplication.
+ */
+ if (encrypt) {
+ err = fscrypt_inherit_context(dir, inode, handle, true);
+ if (err)
+ goto fail_free_drop;
+ }
+
+ if (!(ei->i_flags & EXT4_EA_INODE_FL)) {
+ err = ext4_init_acl(handle, inode, dir);
+ if (err)
+ goto fail_free_drop;
+
+ err = ext4_init_security(handle, inode, dir, qstr);
+ if (err)
+ goto fail_free_drop;
+ }
+
+ if (ext4_has_feature_extents(sb)) {
+ /* set extent flag only for directory, file and normal symlink*/
+ if (S_ISDIR(mode) || S_ISREG(mode) || S_ISLNK(mode)) {
+ ext4_set_inode_flag(inode, EXT4_INODE_EXTENTS);
+ ext4_ext_tree_init(handle, inode);
+ }
+ }
+
+ if (ext4_handle_valid(handle)) {
+ ei->i_sync_tid = handle->h_transaction->t_tid;
+ ei->i_datasync_tid = handle->h_transaction->t_tid;
+ }
+
+ err = ext4_mark_inode_dirty(handle, inode);
+ if (err) {
+ ext4_std_error(sb, err);
+ goto fail_free_drop;
+ }
+
+ ext4_debug("allocating inode %lu\n", inode->i_ino);
+ trace_ext4_allocate_inode(inode, dir, mode);
+ brelse(inode_bitmap_bh);
+ return ret;
+
+fail_free_drop:
+ dquot_free_inode(inode);
+fail_drop:
+ clear_nlink(inode);
+ unlock_new_inode(inode);
+out:
+ dquot_drop(inode);
+ inode->i_flags |= S_NOQUOTA;
+ iput(inode);
+ brelse(inode_bitmap_bh);
+ return ERR_PTR(err);
+}
+
+/* Verify that we are loading a valid orphan from disk */
+struct inode *ext4_orphan_get(struct super_block *sb, unsigned long ino)
+{
+ unsigned long max_ino = le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count);
+ ext4_group_t block_group;
+ int bit;
+ struct buffer_head *bitmap_bh = NULL;
+ struct inode *inode = NULL;
+ int err = -EFSCORRUPTED;
+
+ if (ino < EXT4_FIRST_INO(sb) || ino > max_ino)
+ goto bad_orphan;
+
+ block_group = (ino - 1) / EXT4_INODES_PER_GROUP(sb);
+ bit = (ino - 1) % EXT4_INODES_PER_GROUP(sb);
+ bitmap_bh = ext4_read_inode_bitmap(sb, block_group);
+ if (IS_ERR(bitmap_bh))
+ return (struct inode *) bitmap_bh;
+
+ /* Having the inode bit set should be a 100% indicator that this
+ * is a valid orphan (no e2fsck run on fs). Orphans also include
+ * inodes that were being truncated, so we can't check i_nlink==0.
+ */
+ if (!ext4_test_bit(bit, bitmap_bh->b_data))
+ goto bad_orphan;
+
+ inode = ext4_iget(sb, ino);
+ if (IS_ERR(inode)) {
+ err = PTR_ERR(inode);
+ ext4_error(sb, "couldn't read orphan inode %lu (err %d)",
+ ino, err);
+ return inode;
+ }
+
+ /*
+ * If the orphans has i_nlinks > 0 then it should be able to
+ * be truncated, otherwise it won't be removed from the orphan
+ * list during processing and an infinite loop will result.
+ * Similarly, it must not be a bad inode.
+ */
+ if ((inode->i_nlink && !ext4_can_truncate(inode)) ||
+ is_bad_inode(inode))
+ goto bad_orphan;
+
+ if (NEXT_ORPHAN(inode) > max_ino)
+ goto bad_orphan;
+ brelse(bitmap_bh);
+ return inode;
+
+bad_orphan:
+ ext4_error(sb, "bad orphan inode %lu", ino);
+ if (bitmap_bh)
+ printk(KERN_ERR "ext4_test_bit(bit=%d, block=%llu) = %d\n",
+ bit, (unsigned long long)bitmap_bh->b_blocknr,
+ ext4_test_bit(bit, bitmap_bh->b_data));
+ if (inode) {
+ printk(KERN_ERR "is_bad_inode(inode)=%d\n",
+ is_bad_inode(inode));
+ printk(KERN_ERR "NEXT_ORPHAN(inode)=%u\n",
+ NEXT_ORPHAN(inode));
+ printk(KERN_ERR "max_ino=%lu\n", max_ino);
+ printk(KERN_ERR "i_nlink=%u\n", inode->i_nlink);
+ /* Avoid freeing blocks if we got a bad deleted inode */
+ if (inode->i_nlink == 0)
+ inode->i_blocks = 0;
+ iput(inode);
+ }
+ brelse(bitmap_bh);
+ return ERR_PTR(err);
+}
+
+unsigned long ext4_count_free_inodes(struct super_block *sb)
+{
+ unsigned long desc_count;
+ struct ext4_group_desc *gdp;
+ ext4_group_t i, ngroups = ext4_get_groups_count(sb);
+#ifdef EXT4FS_DEBUG
+ struct ext4_super_block *es;
+ unsigned long bitmap_count, x;
+ struct buffer_head *bitmap_bh = NULL;
+
+ es = EXT4_SB(sb)->s_es;
+ desc_count = 0;
+ bitmap_count = 0;
+ gdp = NULL;
+ for (i = 0; i < ngroups; i++) {
+ gdp = ext4_get_group_desc(sb, i, NULL);
+ if (!gdp)
+ continue;
+ desc_count += ext4_free_inodes_count(sb, gdp);
+ brelse(bitmap_bh);
+ bitmap_bh = ext4_read_inode_bitmap(sb, i);
+ if (IS_ERR(bitmap_bh)) {
+ bitmap_bh = NULL;
+ continue;
+ }
+
+ x = ext4_count_free(bitmap_bh->b_data,
+ EXT4_INODES_PER_GROUP(sb) / 8);
+ printk(KERN_DEBUG "group %lu: stored = %d, counted = %lu\n",
+ (unsigned long) i, ext4_free_inodes_count(sb, gdp), x);
+ bitmap_count += x;
+ }
+ brelse(bitmap_bh);
+ printk(KERN_DEBUG "ext4_count_free_inodes: "
+ "stored = %u, computed = %lu, %lu\n",
+ le32_to_cpu(es->s_free_inodes_count), desc_count, bitmap_count);
+ return desc_count;
+#else
+ desc_count = 0;
+ for (i = 0; i < ngroups; i++) {
+ gdp = ext4_get_group_desc(sb, i, NULL);
+ if (!gdp)
+ continue;
+ desc_count += ext4_free_inodes_count(sb, gdp);
+ cond_resched();
+ }
+ return desc_count;
+#endif
+}
+
+/* Called at mount-time, super-block is locked */
+unsigned long ext4_count_dirs(struct super_block * sb)
+{
+ unsigned long count = 0;
+ ext4_group_t i, ngroups = ext4_get_groups_count(sb);
+
+ for (i = 0; i < ngroups; i++) {
+ struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
+ if (!gdp)
+ continue;
+ count += ext4_used_dirs_count(sb, gdp);
+ }
+ return count;
+}
+
+/*
+ * Zeroes not yet zeroed inode table - just write zeroes through the whole
+ * inode table. Must be called without any spinlock held. The only place
+ * where it is called from on active part of filesystem is ext4lazyinit
+ * thread, so we do not need any special locks, however we have to prevent
+ * inode allocation from the current group, so we take alloc_sem lock, to
+ * block ext4_new_inode() until we are finished.
+ */
+int ext4_init_inode_table(struct super_block *sb, ext4_group_t group,
+ int barrier)
+{
+ struct ext4_group_info *grp = ext4_get_group_info(sb, group);
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+ struct ext4_group_desc *gdp = NULL;
+ struct buffer_head *group_desc_bh;
+ handle_t *handle;
+ ext4_fsblk_t blk;
+ int num, ret = 0, used_blks = 0;
+
+ /* This should not happen, but just to be sure check this */
+ if (sb_rdonly(sb)) {
+ ret = 1;
+ goto out;
+ }
+
+ gdp = ext4_get_group_desc(sb, group, &group_desc_bh);
+ if (!gdp)
+ goto out;
+
+ /*
+ * We do not need to lock this, because we are the only one
+ * handling this flag.
+ */
+ if (gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED))
+ goto out;
+
+ handle = ext4_journal_start_sb(sb, EXT4_HT_MISC, 1);
+ if (IS_ERR(handle)) {
+ ret = PTR_ERR(handle);
+ goto out;
+ }
+
+ down_write(&grp->alloc_sem);
+ /*
+ * If inode bitmap was already initialized there may be some
+ * used inodes so we need to skip blocks with used inodes in
+ * inode table.
+ */
+ if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_UNINIT)))
+ used_blks = DIV_ROUND_UP((EXT4_INODES_PER_GROUP(sb) -
+ ext4_itable_unused_count(sb, gdp)),
+ sbi->s_inodes_per_block);
+
+ if ((used_blks < 0) || (used_blks > sbi->s_itb_per_group) ||
+ ((group == 0) && ((EXT4_INODES_PER_GROUP(sb) -
+ ext4_itable_unused_count(sb, gdp)) <
+ EXT4_FIRST_INO(sb)))) {
+ ext4_error(sb, "Something is wrong with group %u: "
+ "used itable blocks: %d; "
+ "itable unused count: %u",
+ group, used_blks,
+ ext4_itable_unused_count(sb, gdp));
+ ret = 1;
+ goto err_out;
+ }
+
+ blk = ext4_inode_table(sb, gdp) + used_blks;
+ num = sbi->s_itb_per_group - used_blks;
+
+ BUFFER_TRACE(group_desc_bh, "get_write_access");
+ ret = ext4_journal_get_write_access(handle,
+ group_desc_bh);
+ if (ret)
+ goto err_out;
+
+ /*
+ * Skip zeroout if the inode table is full. But we set the ZEROED
+ * flag anyway, because obviously, when it is full it does not need
+ * further zeroing.
+ */
+ if (unlikely(num == 0))
+ goto skip_zeroout;
+
+ ext4_debug("going to zero out inode table in group %d\n",
+ group);
+ ret = sb_issue_zeroout(sb, blk, num, GFP_NOFS);
+ if (ret < 0)
+ goto err_out;
+ if (barrier)
+ blkdev_issue_flush(sb->s_bdev, GFP_NOFS, NULL);
+
+skip_zeroout:
+ ext4_lock_group(sb, group);
+ gdp->bg_flags |= cpu_to_le16(EXT4_BG_INODE_ZEROED);
+ ext4_group_desc_csum_set(sb, group, gdp);
+ ext4_unlock_group(sb, group);
+
+ BUFFER_TRACE(group_desc_bh,
+ "call ext4_handle_dirty_metadata");
+ ret = ext4_handle_dirty_metadata(handle, NULL,
+ group_desc_bh);
+
+err_out:
+ up_write(&grp->alloc_sem);
+ ext4_journal_stop(handle);
+out:
+ return ret;
+}