[Patch 16/18] fs/logfs/progs/fsck.c
Jörn Engel
joern at lazybastard.org
Sun Jun 3 15:00:24 EDT 2007
--- /dev/null 2007-03-13 19:15:28.862769062 +0100
+++ linux-2.6.21logfs/fs/logfs/progs/fsck.c 2007-06-03 19:18:57.000000000 +0200
@@ -0,0 +1,316 @@
+/*
+ * fs/logfs/prog/fsck.c - filesystem check
+ *
+ * As should be obvious for Linux kernel code, license is GPLv2
+ *
+ * Copyright (c) 2005-2007 Joern Engel
+ *
+ * In principle this could get moved to userspace. However it might still
+ * make some sense to keep it in the kernel. It is a pure checker and will
+ * only report problems, not attempt to repair them.
+ */
+#include "../logfs.h"
+
+static u64 used_bytes;
+static u64 free_bytes;
+static u64 last_ino;
+static u64 *inode_bytes;
+static u64 *inode_links;
+
+/*
+ * Pass 1: blocks
+ */
+
+static u32 logfs_free_bytes(struct super_block *sb, u32 segno)
+{
+ struct logfs_super *super = logfs_super(sb);
+ struct logfs_segment_header sh;
+ struct logfs_object_header h;
+ u64 ofs, ino, pos;
+ u32 seg_ofs, free, size;
+ u16 len;
+ int err;
+ void *reserved;
+
+ /* Some segments are reserved. Just pretend they were all valid */
+ reserved = btree_lookup(&super->s_reserved_segments, segno);
+ if (reserved)
+ return 0;
+
+ err = wbuf_read(sb, dev_ofs(sb, segno, 0), sizeof(sh), &sh);
+ BUG_ON(err);
+ if (!memchr_inv(&sh, 0xff, sizeof(sh)))
+ return super->s_segsize;
+
+ free = super->s_segsize;
+ for (seg_ofs = sizeof(h); seg_ofs + sizeof(h) < super->s_segsize; ) {
+ wbuf_read(sb, dev_ofs(sb, segno, seg_ofs), sizeof(h), &h);
+ BUG_ON(err);
+ if (!memchr_inv(&h, 0xff, sizeof(h)))
+ break;
+
+ ofs = dev_ofs(sb, segno, seg_ofs);
+ ino = be64_to_cpu(h.ino);
+ pos = be64_to_cpu(h.pos);
+ len = be16_to_cpu(h.len);
+ size = (u32)be16_to_cpu(h.len) + sizeof(h);
+ if (logfs_is_valid_block(sb, ofs, ino, pos)) {
+ if (sh.level != 0)
+ len = sb->s_blocksize;
+ inode_bytes[ino] += len + sizeof(h);
+ free -= len + sizeof(h);
+ }
+ seg_ofs += size;
+ }
+ return free;
+}
+
+static void logfsck_blocks(struct super_block *sb)
+{
+ struct logfs_super *super = logfs_super(sb);
+ int i;
+ int free;
+
+ printk(KERN_INFO);
+ for (i=0; i<super->s_no_segs; i++) {
+ free = logfs_free_bytes(sb, i);
+ free_bytes += free;
+ printk(" %5x", free);
+ if (i % 8 == 7)
+ printk("\n" KERN_INFO);
+ }
+ printk("\n");
+}
+
+/*
+ * Pass 2: directories
+ */
+
+static noinline int read_one_dd(struct inode *dir, loff_t pos, u64 *ino,
+ u8 *type)
+{
+ struct logfs_disk_dentry dd;
+ int err;
+
+ err = logfs_inode_read(dir, &dd, sizeof(dd), pos);
+ if (err)
+ return err;
+ *ino = be64_to_cpu(dd.ino);
+ *type = dd.type;
+ return 0;
+}
+
+static s64 dir_seek_data(struct inode *inode, s64 pos)
+{
+ s64 new_pos = logfs_seek_data(inode, pos);
+
+ return max((s64)pos, new_pos - 1);
+}
+
+static int __logfsck_dirs(struct inode *dir)
+{
+ struct inode *inode;
+ loff_t pos;
+ u64 ino;
+ u8 type;
+ int cookie, err, ret = 0;
+
+ for (pos=0; ; pos++) {
+ err = read_one_dd(dir, pos, &ino, &type);
+ if (err == -ENODATA) {
+ /* dentry was deleted */
+ pos = dir_seek_data(dir, pos);
+ continue;
+ }
+ if (err == -EOF)
+ break;
+ if (err)
+ goto error0;
+
+ err = -EIO;
+ if (ino > last_ino) {
+ printk(KERN_INFO "ino %llx > last_ino %llx\n",
+ ino, last_ino);
+ goto error0;
+ }
+ inode = logfs_iget(dir->i_sb, ino, &cookie);
+ if (!inode) {
+ printk(KERN_INFO "Could not find inode #%llx\n", ino);
+ goto error0;
+ }
+ if (type != logfs_type(inode)) {
+ printk(KERN_INFO "dd type %x != inode type %x\n",
+ type, logfs_type(inode));
+ goto error1;
+ }
+ inode_links[ino]++;
+ err = 0;
+ if (type == DT_DIR) {
+ inode_links[dir->i_ino]++;
+ inode_links[ino]++;
+ err = __logfsck_dirs(inode);
+ }
+error1:
+ logfs_iput(inode, cookie);
+error0:
+ if (!ret)
+ ret = err;
+ continue;
+ }
+ return 1;
+}
+
+static int logfsck_dirs(struct super_block *sb)
+{
+ struct inode *dir;
+ int cookie;
+
+ dir = logfs_iget(sb, LOGFS_INO_ROOT, &cookie);
+ if (!dir)
+ return 0;
+
+ inode_links[LOGFS_INO_MASTER] += 1;
+ inode_links[LOGFS_INO_ROOT] += 2;
+ __logfsck_dirs(dir);
+
+ logfs_iput(dir, cookie);
+ return 1;
+}
+
+/*
+ * Pass 3: inodes
+ */
+
+static int logfs_check_inode(struct inode *inode)
+{
+ struct logfs_inode *li = logfs_inode(inode);
+ u64 bytes0 = li->li_used_bytes;
+ u64 bytes1 = inode_bytes[inode->i_ino];
+ u64 links0 = inode->i_nlink;
+ u64 links1 = inode_links[inode->i_ino];
+
+ if (bytes0 || bytes1 || links0 || links1
+ || inode->i_ino == logfs_super(inode->i_sb)->s_last_ino)
+ printk(KERN_INFO "%lx: %llx(%llx) bytes, %llx(%llx) links\n",
+ inode->i_ino, bytes0, bytes1, links0, links1);
+ used_bytes += bytes0;
+ return (bytes0 == bytes1) && (links0 == links1);
+}
+
+static int logfs_check_ino(struct super_block *sb, u64 ino)
+{
+ struct inode *inode;
+ int ret, cookie;
+
+ inode = logfs_iget(sb, ino, &cookie);
+ if (!inode)
+ return 1;
+ ret = logfs_check_inode(inode);
+ logfs_iput(inode, cookie);
+ return ret;
+}
+
+static int logfsck_inodes(struct super_block *sb)
+{
+ struct logfs_super *super = logfs_super(sb);
+ s64 i;
+ int ret = 1;
+
+ if (!logfs_check_ino(sb, LOGFS_INO_MASTER))
+ ret = 0;;
+ if (!logfs_check_ino(sb, LOGFS_INO_ROOT))
+ ret = 0;
+ for (i=16; i<super->s_last_ino; i++) {
+ i = dir_seek_data(super->s_master_inode, i);
+ if (!logfs_check_ino(sb, i))
+ ret = 0;;
+ }
+ return ret;
+}
+
+/*
+ * Pass 4: Total blocks
+ */
+
+static int logfsck_stats(struct super_block *sb)
+{
+ struct logfs_super *super = logfs_super(sb);
+ u64 ostore_segs, total, expected;
+ int i, reserved_segs;
+
+ /* one for the superblock */
+ reserved_segs = 1;
+ journal_for_each(i)
+ if (super->s_journal_seg[i])
+ reserved_segs++;
+ reserved_segs += super->s_bad_segments;
+
+ ostore_segs = super->s_no_segs - reserved_segs;
+ expected = ostore_segs << super->s_segshift;
+ total = free_bytes + used_bytes;
+
+ printk(KERN_INFO "free:%8llx, used:%8llx, total:%8llx",
+ free_bytes, used_bytes, expected);
+ if (total > expected)
+ printk(" + %llx\n", total - expected);
+ else if (total < expected)
+ printk(" - %llx\n", expected - total);
+ else
+ printk("\n");
+
+ return total == expected;
+}
+
+static int __logfs_fsck(struct super_block *sb)
+{
+ int ret;
+ int err = 0;
+
+ /* pass 1: check blocks */
+ logfsck_blocks(sb);
+ /* pass 2: check directories */
+ ret = logfsck_dirs(sb);
+ if (!ret) {
+ printk(KERN_ERR "Pass 2: directory check failed\n");
+ err = -EIO;
+ }
+ /* pass 3: check inodes */
+ ret = logfsck_inodes(sb);
+ if (!ret) {
+ printk(KERN_ERR "Pass 3: inode check failed\n");
+ err = -EIO;
+ }
+ /* Pass 4: Total blocks */
+ ret = logfsck_stats(sb);
+ if (!ret) {
+ printk(KERN_ERR "Pass 4: statistic check failed\n");
+ err = -EIO;
+ }
+
+ return err;
+}
+
+int logfs_fsck(struct super_block *sb)
+{
+ struct logfs_super *super = logfs_super(sb);
+ int ret = -ENOMEM;
+
+ used_bytes = 0;
+ free_bytes = 0;
+ last_ino = super->s_last_ino;
+ inode_bytes = kzalloc(last_ino * sizeof(u64), GFP_KERNEL);
+ if (!inode_bytes)
+ return ret;
+ inode_links = kzalloc(last_ino * sizeof(u64), GFP_KERNEL);
+ if (!inode_links)
+ goto err;
+
+ ret = __logfs_fsck(sb);
+
+ kfree(inode_links);
+ inode_links = NULL;
+err:
+ kfree(inode_bytes);
+ inode_bytes = NULL;
+ return ret;
+}
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