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authorKai Bankett <chaosman@ontika.net>2012-02-17 05:59:20 +0100
committerAl Viro <viro@zeniv.linux.org.uk>2012-03-21 02:29:38 +0100
commit5d026c7242201e7c9d0e12fcb2bcaffead9d59fd (patch)
tree3a3663fd35e3077574e30cf705a614ede69925eb /fs/qnx6
parentqnx4fs: small cleanup (diff)
downloadlinux-5d026c7242201e7c9d0e12fcb2bcaffead9d59fd.tar.xz
linux-5d026c7242201e7c9d0e12fcb2bcaffead9d59fd.zip
fs: initial qnx6fs addition
Adds support for qnx6fs readonly support to the linux kernel. * Mount option The option mmi_fs can be used to mount Harman Becker/Audi MMI 3G HDD qnx6fs filesystems. * Documentation A high level filesystem stucture description can be found in the Documentation/filesystems directory. (qnx6.txt) * Additional features - Active (stable) superblock selection - Superblock checksum check (enforced) - Supports mount of qnx6 filesystems with to host different endianess - Automatic endianess detection - Longfilename support (with non-enfocing crc check) - All blocksizes (512, 1024, 2048 and 4096 supported) Signed-off-by: Kai Bankett <chaosman@ontika.net> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'fs/qnx6')
-rw-r--r--fs/qnx6/Kconfig26
-rw-r--r--fs/qnx6/Makefile7
-rw-r--r--fs/qnx6/README8
-rw-r--r--fs/qnx6/dir.c291
-rw-r--r--fs/qnx6/inode.c698
-rw-r--r--fs/qnx6/namei.c42
-rw-r--r--fs/qnx6/qnx6.h135
-rw-r--r--fs/qnx6/super_mmi.c150
8 files changed, 1357 insertions, 0 deletions
diff --git a/fs/qnx6/Kconfig b/fs/qnx6/Kconfig
new file mode 100644
index 000000000000..edbba5c17cc8
--- /dev/null
+++ b/fs/qnx6/Kconfig
@@ -0,0 +1,26 @@
+config QNX6FS_FS
+ tristate "QNX6 file system support (read only)"
+ depends on BLOCK && CRC32
+ help
+ This is the file system used by the real-time operating systems
+ QNX 6 (also called QNX RTP).
+ Further information is available at <http://www.qnx.com/>.
+ Say Y if you intend to mount QNX hard disks or floppies formatted
+ with a mkqnx6fs.
+ However, keep in mind that this currently is a readonly driver!
+
+ To compile this file system support as a module, choose M here: the
+ module will be called qnx6.
+
+ If you don't know whether you need it, then you don't need it:
+ answer N.
+
+config QNX6FS_DEBUG
+ bool "QNX6 debugging information"
+ depends on QNX6FS_FS
+ help
+ Turns on extended debugging output.
+
+ If you are not a developer working on the QNX6FS, you probably don't
+ want this:
+ answer N.
diff --git a/fs/qnx6/Makefile b/fs/qnx6/Makefile
new file mode 100644
index 000000000000..9dd06199afc9
--- /dev/null
+++ b/fs/qnx6/Makefile
@@ -0,0 +1,7 @@
+#
+# Makefile for the linux qnx4-filesystem routines.
+#
+
+obj-$(CONFIG_QNX6FS_FS) += qnx6.o
+
+qnx6-objs := inode.o dir.o namei.o super_mmi.o
diff --git a/fs/qnx6/README b/fs/qnx6/README
new file mode 100644
index 000000000000..116d622026cc
--- /dev/null
+++ b/fs/qnx6/README
@@ -0,0 +1,8 @@
+
+ This is a snapshot of the QNX6 filesystem for Linux.
+ Please send diffs and remarks to <chaosman@ontika.net> .
+
+Credits :
+
+Al Viro <viro@ZenIV.linux.org.uk> (endless patience with me & support ;))
+Kai Bankett <chaosman@ontika.net> (Maintainer)
diff --git a/fs/qnx6/dir.c b/fs/qnx6/dir.c
new file mode 100644
index 000000000000..dc597353db3b
--- /dev/null
+++ b/fs/qnx6/dir.c
@@ -0,0 +1,291 @@
+/*
+ * QNX6 file system, Linux implementation.
+ *
+ * Version : 1.0.0
+ *
+ * History :
+ *
+ * 01-02-2012 by Kai Bankett (chaosman@ontika.net) : first release.
+ * 16-02-2012 pagemap extension by Al Viro
+ *
+ */
+
+#include "qnx6.h"
+
+static unsigned qnx6_lfile_checksum(char *name, unsigned size)
+{
+ unsigned crc = 0;
+ char *end = name + size;
+ while (name < end) {
+ crc = ((crc >> 1) + *(name++)) ^
+ ((crc & 0x00000001) ? 0x80000000 : 0);
+ }
+ return crc;
+}
+
+static struct page *qnx6_get_page(struct inode *dir, unsigned long n)
+{
+ struct address_space *mapping = dir->i_mapping;
+ struct page *page = read_mapping_page(mapping, n, NULL);
+ if (!IS_ERR(page))
+ kmap(page);
+ return page;
+}
+
+static inline unsigned long dir_pages(struct inode *inode)
+{
+ return (inode->i_size+PAGE_CACHE_SIZE-1)>>PAGE_CACHE_SHIFT;
+}
+
+static unsigned last_entry(struct inode *inode, unsigned long page_nr)
+{
+ unsigned long last_byte = inode->i_size;
+ last_byte -= page_nr << PAGE_CACHE_SHIFT;
+ if (last_byte > PAGE_CACHE_SIZE)
+ last_byte = PAGE_CACHE_SIZE;
+ return last_byte / QNX6_DIR_ENTRY_SIZE;
+}
+
+static struct qnx6_long_filename *qnx6_longname(struct super_block *sb,
+ struct qnx6_long_dir_entry *de,
+ struct page **p)
+{
+ struct qnx6_sb_info *sbi = QNX6_SB(sb);
+ u32 s = fs32_to_cpu(sbi, de->de_long_inode); /* in block units */
+ u32 n = s >> (PAGE_CACHE_SHIFT - sb->s_blocksize_bits); /* in pages */
+ /* within page */
+ u32 offs = (s << sb->s_blocksize_bits) & ~PAGE_CACHE_MASK;
+ struct address_space *mapping = sbi->longfile->i_mapping;
+ struct page *page = read_mapping_page(mapping, n, NULL);
+ if (IS_ERR(page))
+ return ERR_CAST(page);
+ kmap(*p = page);
+ return (struct qnx6_long_filename *)(page_address(page) + offs);
+}
+
+static int qnx6_dir_longfilename(struct inode *inode,
+ struct qnx6_long_dir_entry *de,
+ void *dirent, loff_t pos,
+ unsigned de_inode, filldir_t filldir)
+{
+ struct qnx6_long_filename *lf;
+ struct super_block *s = inode->i_sb;
+ struct qnx6_sb_info *sbi = QNX6_SB(s);
+ struct page *page;
+ int lf_size;
+
+ if (de->de_size != 0xff) {
+ /* error - long filename entries always have size 0xff
+ in direntry */
+ printk(KERN_ERR "qnx6: invalid direntry size (%i).\n",
+ de->de_size);
+ return 0;
+ }
+ lf = qnx6_longname(s, de, &page);
+ if (IS_ERR(lf)) {
+ printk(KERN_ERR "qnx6:Error reading longname\n");
+ return 0;
+ }
+
+ lf_size = fs16_to_cpu(sbi, lf->lf_size);
+
+ if (lf_size > QNX6_LONG_NAME_MAX) {
+ QNX6DEBUG((KERN_INFO "file %s\n", lf->lf_fname));
+ printk(KERN_ERR "qnx6:Filename too long (%i)\n", lf_size);
+ qnx6_put_page(page);
+ return 0;
+ }
+
+ /* calc & validate longfilename checksum
+ mmi 3g filesystem does not have that checksum */
+ if (!test_opt(s, MMI_FS) && fs32_to_cpu(sbi, de->de_checksum) !=
+ qnx6_lfile_checksum(lf->lf_fname, lf_size))
+ printk(KERN_INFO "qnx6: long filename checksum error.\n");
+
+ QNX6DEBUG((KERN_INFO "qnx6_readdir:%.*s inode:%u\n",
+ lf_size, lf->lf_fname, de_inode));
+ if (filldir(dirent, lf->lf_fname, lf_size, pos, de_inode,
+ DT_UNKNOWN) < 0) {
+ qnx6_put_page(page);
+ return 0;
+ }
+
+ qnx6_put_page(page);
+ /* success */
+ return 1;
+}
+
+static int qnx6_readdir(struct file *filp, void *dirent, filldir_t filldir)
+{
+ struct inode *inode = filp->f_path.dentry->d_inode;
+ struct super_block *s = inode->i_sb;
+ struct qnx6_sb_info *sbi = QNX6_SB(s);
+ loff_t pos = filp->f_pos & (QNX6_DIR_ENTRY_SIZE - 1);
+ unsigned long npages = dir_pages(inode);
+ unsigned long n = pos >> PAGE_CACHE_SHIFT;
+ unsigned start = (pos & ~PAGE_CACHE_MASK) / QNX6_DIR_ENTRY_SIZE;
+ bool done = false;
+
+ if (filp->f_pos >= inode->i_size)
+ return 0;
+
+ for ( ; !done && n < npages; n++, start = 0) {
+ struct page *page = qnx6_get_page(inode, n);
+ int limit = last_entry(inode, n);
+ struct qnx6_dir_entry *de;
+ int i = start;
+
+ if (IS_ERR(page)) {
+ printk(KERN_ERR "qnx6_readdir: read failed\n");
+ filp->f_pos = (n + 1) << PAGE_CACHE_SHIFT;
+ return PTR_ERR(page);
+ }
+ de = ((struct qnx6_dir_entry *)page_address(page)) + start;
+ for (; i < limit; i++, de++, pos += QNX6_DIR_ENTRY_SIZE) {
+ int size = de->de_size;
+ u32 no_inode = fs32_to_cpu(sbi, de->de_inode);
+
+ if (!no_inode || !size)
+ continue;
+
+ if (size > QNX6_SHORT_NAME_MAX) {
+ /* long filename detected
+ get the filename from long filename
+ structure / block */
+ if (!qnx6_dir_longfilename(inode,
+ (struct qnx6_long_dir_entry *)de,
+ dirent, pos, no_inode,
+ filldir)) {
+ done = true;
+ break;
+ }
+ } else {
+ QNX6DEBUG((KERN_INFO "qnx6_readdir:%.*s"
+ " inode:%u\n", size, de->de_fname,
+ no_inode));
+ if (filldir(dirent, de->de_fname, size,
+ pos, no_inode, DT_UNKNOWN)
+ < 0) {
+ done = true;
+ break;
+ }
+ }
+ }
+ qnx6_put_page(page);
+ }
+ filp->f_pos = pos;
+ return 0;
+}
+
+/*
+ * check if the long filename is correct.
+ */
+static unsigned qnx6_long_match(int len, const char *name,
+ struct qnx6_long_dir_entry *de, struct inode *dir)
+{
+ struct super_block *s = dir->i_sb;
+ struct qnx6_sb_info *sbi = QNX6_SB(s);
+ struct page *page;
+ int thislen;
+ struct qnx6_long_filename *lf = qnx6_longname(s, de, &page);
+
+ if (IS_ERR(lf))
+ return 0;
+
+ thislen = fs16_to_cpu(sbi, lf->lf_size);
+ if (len != thislen) {
+ qnx6_put_page(page);
+ return 0;
+ }
+ if (memcmp(name, lf->lf_fname, len) == 0) {
+ qnx6_put_page(page);
+ return fs32_to_cpu(sbi, de->de_inode);
+ }
+ qnx6_put_page(page);
+ return 0;
+}
+
+/*
+ * check if the filename is correct.
+ */
+static unsigned qnx6_match(struct super_block *s, int len, const char *name,
+ struct qnx6_dir_entry *de)
+{
+ struct qnx6_sb_info *sbi = QNX6_SB(s);
+ if (memcmp(name, de->de_fname, len) == 0)
+ return fs32_to_cpu(sbi, de->de_inode);
+ return 0;
+}
+
+
+unsigned qnx6_find_entry(int len, struct inode *dir, const char *name,
+ struct page **res_page)
+{
+ struct super_block *s = dir->i_sb;
+ struct qnx6_inode_info *ei = QNX6_I(dir);
+ struct page *page = NULL;
+ unsigned long start, n;
+ unsigned long npages = dir_pages(dir);
+ unsigned ino;
+ struct qnx6_dir_entry *de;
+ struct qnx6_long_dir_entry *lde;
+
+ *res_page = NULL;
+
+ if (npages == 0)
+ return 0;
+ start = ei->i_dir_start_lookup;
+ if (start >= npages)
+ start = 0;
+ n = start;
+
+ do {
+ page = qnx6_get_page(dir, n);
+ if (!IS_ERR(page)) {
+ int limit = last_entry(dir, n);
+ int i;
+
+ de = (struct qnx6_dir_entry *)page_address(page);
+ for (i = 0; i < limit; i++, de++) {
+ if (len <= QNX6_SHORT_NAME_MAX) {
+ /* short filename */
+ if (len != de->de_size)
+ continue;
+ ino = qnx6_match(s, len, name, de);
+ if (ino)
+ goto found;
+ } else if (de->de_size == 0xff) {
+ /* deal with long filename */
+ lde = (struct qnx6_long_dir_entry *)de;
+ ino = qnx6_long_match(len,
+ name, lde, dir);
+ if (ino)
+ goto found;
+ } else
+ printk(KERN_ERR "qnx6: undefined "
+ "filename size in inode.\n");
+ }
+ qnx6_put_page(page);
+ }
+
+ if (++n >= npages)
+ n = 0;
+ } while (n != start);
+ return 0;
+
+found:
+ *res_page = page;
+ ei->i_dir_start_lookup = n;
+ return ino;
+}
+
+const struct file_operations qnx6_dir_operations = {
+ .llseek = generic_file_llseek,
+ .read = generic_read_dir,
+ .readdir = qnx6_readdir,
+ .fsync = generic_file_fsync,
+};
+
+const struct inode_operations qnx6_dir_inode_operations = {
+ .lookup = qnx6_lookup,
+};
diff --git a/fs/qnx6/inode.c b/fs/qnx6/inode.c
new file mode 100644
index 000000000000..e44012dc5645
--- /dev/null
+++ b/fs/qnx6/inode.c
@@ -0,0 +1,698 @@
+/*
+ * QNX6 file system, Linux implementation.
+ *
+ * Version : 1.0.0
+ *
+ * History :
+ *
+ * 01-02-2012 by Kai Bankett (chaosman@ontika.net) : first release.
+ * 16-02-2012 pagemap extension by Al Viro
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/highuid.h>
+#include <linux/pagemap.h>
+#include <linux/buffer_head.h>
+#include <linux/writeback.h>
+#include <linux/statfs.h>
+#include <linux/parser.h>
+#include <linux/seq_file.h>
+#include <linux/mount.h>
+#include <linux/crc32.h>
+#include <linux/mpage.h>
+#include "qnx6.h"
+
+static const struct super_operations qnx6_sops;
+
+static void qnx6_put_super(struct super_block *sb);
+static struct inode *qnx6_alloc_inode(struct super_block *sb);
+static void qnx6_destroy_inode(struct inode *inode);
+static int qnx6_remount(struct super_block *sb, int *flags, char *data);
+static int qnx6_statfs(struct dentry *dentry, struct kstatfs *buf);
+static int qnx6_show_options(struct seq_file *seq, struct dentry *root);
+
+static const struct super_operations qnx6_sops = {
+ .alloc_inode = qnx6_alloc_inode,
+ .destroy_inode = qnx6_destroy_inode,
+ .put_super = qnx6_put_super,
+ .statfs = qnx6_statfs,
+ .remount_fs = qnx6_remount,
+ .show_options = qnx6_show_options,
+};
+
+static int qnx6_show_options(struct seq_file *seq, struct dentry *root)
+{
+ struct super_block *sb = root->d_sb;
+ struct qnx6_sb_info *sbi = QNX6_SB(sb);
+
+ if (sbi->s_mount_opt & QNX6_MOUNT_MMI_FS)
+ seq_puts(seq, ",mmi_fs");
+ return 0;
+}
+
+static int qnx6_remount(struct super_block *sb, int *flags, char *data)
+{
+ *flags |= MS_RDONLY;
+ return 0;
+}
+
+static unsigned qnx6_get_devblock(struct super_block *sb, __fs32 block)
+{
+ struct qnx6_sb_info *sbi = QNX6_SB(sb);
+ return fs32_to_cpu(sbi, block) + sbi->s_blks_off;
+}
+
+static unsigned qnx6_block_map(struct inode *inode, unsigned iblock);
+
+static int qnx6_get_block(struct inode *inode, sector_t iblock,
+ struct buffer_head *bh, int create)
+{
+ unsigned phys;
+
+ QNX6DEBUG((KERN_INFO "qnx6: qnx6_get_block inode=[%ld] iblock=[%ld]\n",
+ inode->i_ino, (unsigned long)iblock));
+
+ phys = qnx6_block_map(inode, iblock);
+ if (phys) {
+ /* logical block is before EOF */
+ map_bh(bh, inode->i_sb, phys);
+ }
+ return 0;
+}
+
+static int qnx6_check_blockptr(__fs32 ptr)
+{
+ if (ptr == ~(__fs32)0) {
+ printk(KERN_ERR "qnx6: hit unused blockpointer.\n");
+ return 0;
+ }
+ return 1;
+}
+
+static int qnx6_readpage(struct file *file, struct page *page)
+{
+ return mpage_readpage(page, qnx6_get_block);
+}
+
+static int qnx6_readpages(struct file *file, struct address_space *mapping,
+ struct list_head *pages, unsigned nr_pages)
+{
+ return mpage_readpages(mapping, pages, nr_pages, qnx6_get_block);
+}
+
+/*
+ * returns the block number for the no-th element in the tree
+ * inodebits requred as there are multiple inodes in one inode block
+ */
+static unsigned qnx6_block_map(struct inode *inode, unsigned no)
+{
+ struct super_block *s = inode->i_sb;
+ struct qnx6_sb_info *sbi = QNX6_SB(s);
+ struct qnx6_inode_info *ei = QNX6_I(inode);
+ unsigned block = 0;
+ struct buffer_head *bh;
+ __fs32 ptr;
+ int levelptr;
+ int ptrbits = sbi->s_ptrbits;
+ int bitdelta;
+ u32 mask = (1 << ptrbits) - 1;
+ int depth = ei->di_filelevels;
+ int i;
+
+ bitdelta = ptrbits * depth;
+ levelptr = no >> bitdelta;
+
+ if (levelptr > QNX6_NO_DIRECT_POINTERS - 1) {
+ printk(KERN_ERR "qnx6:Requested file block number (%u) too big.",
+ no);
+ return 0;
+ }
+
+ block = qnx6_get_devblock(s, ei->di_block_ptr[levelptr]);
+
+ for (i = 0; i < depth; i++) {
+ bh = sb_bread(s, block);
+ if (!bh) {
+ printk(KERN_ERR "qnx6:Error reading block (%u)\n",
+ block);
+ return 0;
+ }
+ bitdelta -= ptrbits;
+ levelptr = (no >> bitdelta) & mask;
+ ptr = ((__fs32 *)bh->b_data)[levelptr];
+
+ if (!qnx6_check_blockptr(ptr))
+ return 0;
+
+ block = qnx6_get_devblock(s, ptr);
+ brelse(bh);
+ }
+ return block;
+}
+
+static int qnx6_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+ struct super_block *sb = dentry->d_sb;
+ struct qnx6_sb_info *sbi = QNX6_SB(sb);
+ u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
+
+ buf->f_type = sb->s_magic;
+ buf->f_bsize = sb->s_blocksize;
+ buf->f_blocks = fs32_to_cpu(sbi, sbi->sb->sb_num_blocks);
+ buf->f_bfree = fs32_to_cpu(sbi, sbi->sb->sb_free_blocks);
+ buf->f_files = fs32_to_cpu(sbi, sbi->sb->sb_num_inodes);
+ buf->f_ffree = fs32_to_cpu(sbi, sbi->sb->sb_free_inodes);
+ buf->f_bavail = buf->f_bfree;
+ buf->f_namelen = QNX6_LONG_NAME_MAX;
+ buf->f_fsid.val[0] = (u32)id;
+ buf->f_fsid.val[1] = (u32)(id >> 32);
+
+ return 0;
+}
+
+/*
+ * Check the root directory of the filesystem to make sure
+ * it really _is_ a qnx6 filesystem, and to check the size
+ * of the directory entry.
+ */
+static const char *qnx6_checkroot(struct super_block *s)
+{
+ static char match_root[2][3] = {".\0\0", "..\0"};
+ int i, error = 0;
+ struct qnx6_dir_entry *dir_entry;
+ struct inode *root = s->s_root->d_inode;
+ struct address_space *mapping = root->i_mapping;
+ struct page *page = read_mapping_page(mapping, 0, NULL);
+ if (IS_ERR(page))
+ return "error reading root directory";
+ kmap(page);
+ dir_entry = page_address(page);
+ for (i = 0; i < 2; i++) {
+ /* maximum 3 bytes - due to match_root limitation */
+ if (strncmp(dir_entry[i].de_fname, match_root[i], 3))
+ error = 1;
+ }
+ qnx6_put_page(page);
+ if (error)
+ return "error reading root directory.";
+ return NULL;
+}
+
+#ifdef CONFIG_QNX6FS_DEBUG
+void qnx6_superblock_debug(struct qnx6_super_block *sb, struct super_block *s)
+{
+ struct qnx6_sb_info *sbi = QNX6_SB(s);
+
+ QNX6DEBUG((KERN_INFO "magic: %08x\n",
+ fs32_to_cpu(sbi, sb->sb_magic)));
+ QNX6DEBUG((KERN_INFO "checksum: %08x\n",
+ fs32_to_cpu(sbi, sb->sb_checksum)));
+ QNX6DEBUG((KERN_INFO "serial: %llx\n",
+ fs64_to_cpu(sbi, sb->sb_serial)));
+ QNX6DEBUG((KERN_INFO "flags: %08x\n",
+ fs32_to_cpu(sbi, sb->sb_flags)));
+ QNX6DEBUG((KERN_INFO "blocksize: %08x\n",
+ fs32_to_cpu(sbi, sb->sb_blocksize)));
+ QNX6DEBUG((KERN_INFO "num_inodes: %08x\n",
+ fs32_to_cpu(sbi, sb->sb_num_inodes)));
+ QNX6DEBUG((KERN_INFO "free_inodes: %08x\n",
+ fs32_to_cpu(sbi, sb->sb_free_inodes)));
+ QNX6DEBUG((KERN_INFO "num_blocks: %08x\n",
+ fs32_to_cpu(sbi, sb->sb_num_blocks)));
+ QNX6DEBUG((KERN_INFO "free_blocks: %08x\n",
+ fs32_to_cpu(sbi, sb->sb_free_blocks)));
+ QNX6DEBUG((KERN_INFO "inode_levels: %02x\n",
+ sb->Inode.levels));
+}
+#endif
+
+enum {
+ Opt_mmifs,
+ Opt_err
+};
+
+static const match_table_t tokens = {
+ {Opt_mmifs, "mmi_fs"},
+ {Opt_err, NULL}
+};
+
+static int qnx6_parse_options(char *options, struct super_block *sb)
+{
+ char *p;
+ struct qnx6_sb_info *sbi = QNX6_SB(sb);
+ substring_t args[MAX_OPT_ARGS];
+
+ if (!options)
+ return 1;
+
+ while ((p = strsep(&options, ",")) != NULL) {
+ int token;
+ if (!*p)
+ continue;
+
+ token = match_token(p, tokens, args);
+ switch (token) {
+ case Opt_mmifs:
+ set_opt(sbi->s_mount_opt, MMI_FS);
+ break;
+ default:
+ return 0;
+ }
+ }
+ return 1;
+}
+
+static struct buffer_head *qnx6_check_first_superblock(struct super_block *s,
+ int offset, int silent)
+{
+ struct qnx6_sb_info *sbi = QNX6_SB(s);
+ struct buffer_head *bh;
+ struct qnx6_super_block *sb;
+
+ /* Check the superblock signatures
+ start with the first superblock */
+ bh = sb_bread(s, offset);
+ if (!bh) {
+ printk(KERN_ERR "qnx6: unable to read the first superblock\n");
+ return NULL;
+ }
+ sb = (struct qnx6_super_block *)bh->b_data;
+ if (fs32_to_cpu(sbi, sb->sb_magic) != QNX6_SUPER_MAGIC) {
+ sbi->s_bytesex = BYTESEX_BE;
+ if (fs32_to_cpu(sbi, sb->sb_magic) == QNX6_SUPER_MAGIC) {
+ /* we got a big endian fs */
+ QNX6DEBUG((KERN_INFO "qnx6: fs got different"
+ " endianess.\n"));
+ return bh;
+ } else
+ sbi->s_bytesex = BYTESEX_LE;
+ if (!silent) {
+ if (offset == 0) {
+ printk(KERN_ERR "qnx6: wrong signature (magic)"
+ " in superblock #1.\n");
+ } else {
+ printk(KERN_INFO "qnx6: wrong signature (magic)"
+ " at position (0x%lx) - will try"
+ " alternative position (0x0000).\n",
+ offset * s->s_blocksize);
+ }
+ }
+ brelse(bh);
+ return NULL;
+ }
+ return bh;
+}
+
+static struct inode *qnx6_private_inode(struct super_block *s,
+ struct qnx6_root_node *p);
+
+static int qnx6_fill_super(struct super_block *s, void *data, int silent)
+{
+ struct buffer_head *bh1 = NULL, *bh2 = NULL;
+ struct qnx6_super_block *sb1 = NULL, *sb2 = NULL;
+ struct qnx6_sb_info *sbi;
+ struct inode *root;
+ const char *errmsg;
+ struct qnx6_sb_info *qs;
+ int ret = -EINVAL;
+ u64 offset;
+ int bootblock_offset = QNX6_BOOTBLOCK_SIZE;
+
+ qs = kzalloc(sizeof(struct qnx6_sb_info), GFP_KERNEL);
+ if (!qs)
+ return -ENOMEM;
+ s->s_fs_info = qs;
+
+ /* Superblock always is 512 Byte long */
+ if (!sb_set_blocksize(s, QNX6_SUPERBLOCK_SIZE)) {
+ printk(KERN_ERR "qnx6: unable to set blocksize\n");
+ goto outnobh;
+ }
+
+ /* parse the mount-options */
+ if (!qnx6_parse_options((char *) data, s)) {
+ printk(KERN_ERR "qnx6: invalid mount options.\n");
+ goto outnobh;
+ }
+ if (test_opt(s, MMI_FS)) {
+ sb1 = qnx6_mmi_fill_super(s, silent);
+ if (sb1)
+ goto mmi_success;
+ else
+ goto outnobh;
+ }
+ sbi = QNX6_SB(s);
+ sbi->s_bytesex = BYTESEX_LE;
+ /* Check the superblock signatures
+ start with the first superblock */
+ bh1 = qnx6_check_first_superblock(s,
+ bootblock_offset / QNX6_SUPERBLOCK_SIZE, silent);
+ if (!bh1) {
+ /* try again without bootblock offset */
+ bh1 = qnx6_check_first_superblock(s, 0, silent);
+ if (!bh1) {
+ printk(KERN_ERR "qnx6: unable to read the first superblock\n");
+ goto outnobh;
+ }
+ /* seems that no bootblock at partition start */
+ bootblock_offset = 0;
+ }
+ sb1 = (struct qnx6_super_block *)bh1->b_data;
+
+#ifdef CONFIG_QNX6FS_DEBUG
+ qnx6_superblock_debug(sb1, s);
+#endif
+
+ /* checksum check - start at byte 8 and end at byte 512 */
+ if (fs32_to_cpu(sbi, sb1->sb_checksum) !=
+ crc32_be(0, (char *)(bh1->b_data + 8), 504)) {
+ printk(KERN_ERR "qnx6: superblock #1 checksum error\n");
+ goto out;
+ }
+
+ /* set new blocksize */
+ if (!sb_set_blocksize(s, fs32_to_cpu(sbi, sb1->sb_blocksize))) {
+ printk(KERN_ERR "qnx6: unable to set blocksize\n");
+ goto out;
+ }
+ /* blocksize invalidates bh - pull it back in */
+ brelse(bh1);
+ bh1 = sb_bread(s, bootblock_offset >> s->s_blocksize_bits);
+ if (!bh1)
+ goto outnobh;
+ sb1 = (struct qnx6_super_block *)bh1->b_data;
+
+ /* calculate second superblock blocknumber */
+ offset = fs32_to_cpu(sbi, sb1->sb_num_blocks) +
+ (bootblock_offset >> s->s_blocksize_bits) +
+ (QNX6_SUPERBLOCK_AREA >> s->s_blocksize_bits);
+
+ /* set bootblock offset */
+ sbi->s_blks_off = (bootblock_offset >> s->s_blocksize_bits) +
+ (QNX6_SUPERBLOCK_AREA >> s->s_blocksize_bits);
+
+ /* next the second superblock */
+ bh2 = sb_bread(s, offset);
+ if (!bh2) {
+ printk(KERN_ERR "qnx6: unable to read the second superblock\n");
+ goto out;
+ }
+ sb2 = (struct qnx6_super_block *)bh2->b_data;
+ if (fs32_to_cpu(sbi, sb2->sb_magic) != QNX6_SUPER_MAGIC) {
+ if (!silent)
+ printk(KERN_ERR "qnx6: wrong signature (magic)"
+ " in superblock #2.\n");
+ goto out;
+ }
+
+ /* checksum check - start at byte 8 and end at byte 512 */
+ if (fs32_to_cpu(sbi, sb2->sb_checksum) !=
+ crc32_be(0, (char *)(bh2->b_data + 8), 504)) {
+ printk(KERN_ERR "qnx6: superblock #2 checksum error\n");
+ goto out;
+ }
+
+ if (fs64_to_cpu(sbi, sb1->sb_serial) >=
+ fs64_to_cpu(sbi, sb2->sb_serial)) {
+ /* superblock #1 active */
+ sbi->sb_buf = bh1;
+ sbi->sb = (struct qnx6_super_block *)bh1->b_data;
+ brelse(bh2);
+ printk(KERN_INFO "qnx6: superblock #1 active\n");
+ } else {
+ /* superblock #2 active */
+ sbi->sb_buf = bh2;
+ sbi->sb = (struct qnx6_super_block *)bh2->b_data;
+ brelse(bh1);
+ printk(KERN_INFO "qnx6: superblock #2 active\n");
+ }
+mmi_success:
+ /* sanity check - limit maximum indirect pointer levels */
+ if (sb1->Inode.levels > QNX6_PTR_MAX_LEVELS) {
+ printk(KERN_ERR "qnx6: too many inode levels (max %i, sb %i)\n",
+ QNX6_PTR_MAX_LEVELS, sb1->Inode.levels);
+ goto out;
+ }
+ if (sb1->Longfile.levels > QNX6_PTR_MAX_LEVELS) {
+ printk(KERN_ERR "qnx6: too many longfilename levels"
+ " (max %i, sb %i)\n",
+ QNX6_PTR_MAX_LEVELS, sb1->Longfile.levels);
+ goto out;
+ }
+ s->s_op = &qnx6_sops;
+ s->s_magic = QNX6_SUPER_MAGIC;
+ s->s_flags |= MS_RDONLY; /* Yup, read-only yet */
+
+ /* ease the later tree level calculations */
+ sbi = QNX6_SB(s);
+ sbi->s_ptrbits = ilog2(s->s_blocksize / 4);
+ sbi->inodes = qnx6_private_inode(s, &sb1->Inode);
+ if (!sbi->inodes)
+ goto out;
+ sbi->longfile = qnx6_private_inode(s, &sb1->Longfile);
+ if (!sbi->longfile)
+ goto out1;
+
+ /* prefetch root inode */
+ root = qnx6_iget(s, QNX6_ROOT_INO);
+ if (IS_ERR(root)) {
+ printk(KERN_ERR "qnx6: get inode failed\n");
+ ret = PTR_ERR(root);
+ goto out2;
+ }
+
+ ret = -ENOMEM;
+ s->s_root = d_make_root(root);
+ if (!s->s_root)
+ goto out2;
+
+ ret = -EINVAL;
+ errmsg = qnx6_checkroot(s);
+ if (errmsg != NULL) {
+ if (!silent)
+ printk(KERN_ERR "qnx6: %s\n", errmsg);
+ goto out3;
+ }
+ return 0;
+
+out3:
+ dput(s->s_root);
+ s->s_root = NULL;
+out2:
+ iput(sbi->longfile);
+out1:
+ iput(sbi->inodes);
+out:
+ if (bh1)
+ brelse(bh1);
+ if (bh2)
+ brelse(bh2);
+outnobh:
+ kfree(qs);
+ s->s_fs_info = NULL;
+ return ret;
+}
+
+static void qnx6_put_super(struct super_block *sb)
+{
+ struct qnx6_sb_info *qs = QNX6_SB(sb);
+ brelse(qs->sb_buf);
+ iput(qs->longfile);
+ iput(qs->inodes);
+ kfree(qs);
+ sb->s_fs_info = NULL;
+ return;
+}
+
+static sector_t qnx6_bmap(struct address_space *mapping, sector_t block)
+{
+ return generic_block_bmap(mapping, block, qnx6_get_block);
+}
+static const struct address_space_operations qnx6_aops = {
+ .readpage = qnx6_readpage,
+ .readpages = qnx6_readpages,
+ .bmap = qnx6_bmap
+};
+
+static struct inode *qnx6_private_inode(struct super_block *s,
+ struct qnx6_root_node *p)
+{
+ struct inode *inode = new_inode(s);
+ if (inode) {
+ struct qnx6_inode_info *ei = QNX6_I(inode);
+ struct qnx6_sb_info *sbi = QNX6_SB(s);
+ inode->i_size = fs64_to_cpu(sbi, p->size);
+ memcpy(ei->di_block_ptr, p->ptr, sizeof(p->ptr));
+ ei->di_filelevels = p->levels;
+ inode->i_mode = S_IFREG | S_IRUSR; /* probably wrong */
+ inode->i_mapping->a_ops = &qnx6_aops;
+ }
+ return inode;
+}
+
+struct inode *qnx6_iget(struct super_block *sb, unsigned ino)
+{
+ struct qnx6_sb_info *sbi = QNX6_SB(sb);
+ struct qnx6_inode_entry *raw_inode;
+ struct inode *inode;
+ struct qnx6_inode_info *ei;
+ struct address_space *mapping;
+ struct page *page;
+ u32 n, offs;
+
+ inode = iget_locked(sb, ino);
+ if (!inode)
+ return ERR_PTR(-ENOMEM);
+ if (!(inode->i_state & I_NEW))
+ return inode;
+
+ ei = QNX6_I(inode);
+
+ inode->i_mode = 0;
+
+ if (ino == 0) {
+ printk(KERN_ERR "qnx6: bad inode number on dev %s: %u is "
+ "out of range\n",
+ sb->s_id, ino);
+ iget_failed(inode);
+ return ERR_PTR(-EIO);
+ }
+ n = (ino - 1) >> (PAGE_CACHE_SHIFT - QNX6_INODE_SIZE_BITS);
+ offs = (ino - 1) & (~PAGE_CACHE_MASK >> QNX6_INODE_SIZE_BITS);
+ mapping = sbi->inodes->i_mapping;
+ page = read_mapping_page(mapping, n, NULL);
+ if (IS_ERR(page)) {
+ printk(KERN_ERR "qnx6: major problem: unable to read inode from "
+ "dev %s\n", sb->s_id);
+ iget_failed(inode);
+ return ERR_CAST(page);
+ }
+ kmap(page);
+ raw_inode = ((struct qnx6_inode_entry *)page_address(page)) + offs;
+
+ inode->i_mode = fs16_to_cpu(sbi, raw_inode->di_mode);
+ inode->i_uid = (uid_t)fs32_to_cpu(sbi, raw_inode->di_uid);
+ inode->i_gid = (gid_t)fs32_to_cpu(sbi, raw_inode->di_gid);
+ inode->i_size = fs64_to_cpu(sbi, raw_inode->di_size);
+ inode->i_mtime.tv_sec = fs32_to_cpu(sbi, raw_inode->di_mtime);
+ inode->i_mtime.tv_nsec = 0;
+ inode->i_atime.tv_sec = fs32_to_cpu(sbi, raw_inode->di_atime);
+ inode->i_atime.tv_nsec = 0;
+ inode->i_ctime.tv_sec = fs32_to_cpu(sbi, raw_inode->di_ctime);
+ inode->i_ctime.tv_nsec = 0;
+
+ /* calc blocks based on 512 byte blocksize */
+ inode->i_blocks = (inode->i_size + 511) >> 9;
+
+ memcpy(&ei->di_block_ptr, &raw_inode->di_block_ptr,
+ sizeof(raw_inode->di_block_ptr));
+ ei->di_filelevels = raw_inode->di_filelevels;
+
+ if (S_ISREG(inode->i_mode)) {
+ inode->i_fop = &generic_ro_fops;
+ inode->i_mapping->a_ops = &qnx6_aops;
+ } else if (S_ISDIR(inode->i_mode)) {
+ inode->i_op = &qnx6_dir_inode_operations;
+ inode->i_fop = &qnx6_dir_operations;
+ inode->i_mapping->a_ops = &qnx6_aops;
+ } else if (S_ISLNK(inode->i_mode)) {
+ inode->i_op = &page_symlink_inode_operations;
+ inode->i_mapping->a_ops = &qnx6_aops;
+ } else
+ init_special_inode(inode, inode->i_mode, 0);
+ qnx6_put_page(page);
+ unlock_new_inode(inode);
+ return inode;
+}
+
+static struct kmem_cache *qnx6_inode_cachep;
+
+static struct inode *qnx6_alloc_inode(struct super_block *sb)
+{
+ struct qnx6_inode_info *ei;
+ ei = kmem_cache_alloc(qnx6_inode_cachep, GFP_KERNEL);
+ if (!ei)
+ return NULL;
+ return &ei->vfs_inode;
+}
+
+static void qnx6_i_callback(struct rcu_head *head)
+{
+ struct inode *inode = container_of(head, struct inode, i_rcu);
+ INIT_LIST_HEAD(&inode->i_dentry);
+ kmem_cache_free(qnx6_inode_cachep, QNX6_I(inode));
+}
+
+static void qnx6_destroy_inode(struct inode *inode)
+{
+ call_rcu(&inode->i_rcu, qnx6_i_callback);
+}
+
+static void init_once(void *foo)
+{
+ struct qnx6_inode_info *ei = (struct qnx6_inode_info *) foo;
+
+ inode_init_once(&ei->vfs_inode);
+}
+
+static int init_inodecache(void)
+{
+ qnx6_inode_cachep = kmem_cache_create("qnx6_inode_cache",
+ sizeof(struct qnx6_inode_info),
+ 0, (SLAB_RECLAIM_ACCOUNT|
+ SLAB_MEM_SPREAD),
+ init_once);
+ if (!qnx6_inode_cachep)
+ return -ENOMEM;
+ return 0;
+}
+
+static void destroy_inodecache(void)
+{
+ kmem_cache_destroy(qnx6_inode_cachep);
+}
+
+static struct dentry *qnx6_mount(struct file_system_type *fs_type,
+ int flags, const char *dev_name, void *data)
+{
+ return mount_bdev(fs_type, flags, dev_name, data, qnx6_fill_super);
+}
+
+static struct file_system_type qnx6_fs_type = {
+ .owner = THIS_MODULE,
+ .name = "qnx6",
+ .mount = qnx6_mount,
+ .kill_sb = kill_block_super,
+ .fs_flags = FS_REQUIRES_DEV,
+};
+
+static int __init init_qnx6_fs(void)
+{
+ int err;
+
+ err = init_inodecache();
+ if (err)
+ return err;
+
+ err = register_filesystem(&qnx6_fs_type);
+ if (err) {
+ destroy_inodecache();
+ return err;
+ }
+
+ printk(KERN_INFO "QNX6 filesystem 1.0.0 registered.\n");
+ return 0;
+}
+
+static void __exit exit_qnx6_fs(void)
+{
+ unregister_filesystem(&qnx6_fs_type);
+ destroy_inodecache();
+}
+
+module_init(init_qnx6_fs)
+module_exit(exit_qnx6_fs)
+MODULE_LICENSE("GPL");
diff --git a/fs/qnx6/namei.c b/fs/qnx6/namei.c
new file mode 100644
index 000000000000..8a97289e04ad
--- /dev/null
+++ b/fs/qnx6/namei.c
@@ -0,0 +1,42 @@
+/*
+ * QNX6 file system, Linux implementation.
+ *
+ * Version : 1.0.0
+ *
+ * History :
+ *
+ * 01-02-2012 by Kai Bankett (chaosman@ontika.net) : first release.
+ * 16-02-2012 pagemap extension by Al Viro
+ *
+ */
+
+#include "qnx6.h"
+
+struct dentry *qnx6_lookup(struct inode *dir, struct dentry *dentry,
+ struct nameidata *nd)
+{
+ unsigned ino;
+ struct page *page;
+ struct inode *foundinode = NULL;
+ const char *name = dentry->d_name.name;
+ int len = dentry->d_name.len;
+
+ if (len > QNX6_LONG_NAME_MAX)
+ return ERR_PTR(-ENAMETOOLONG);
+
+ ino = qnx6_find_entry(len, dir, name, &page);
+ if (ino) {
+ foundinode = qnx6_iget(dir->i_sb, ino);
+ qnx6_put_page(page);
+ if (IS_ERR(foundinode)) {
+ QNX6DEBUG((KERN_ERR "qnx6: lookup->iget -> "
+ " error %ld\n", PTR_ERR(foundinode)));
+ return ERR_CAST(foundinode);
+ }
+ } else {
+ QNX6DEBUG((KERN_INFO "qnx6_lookup: not found %s\n", name));
+ return NULL;
+ }
+ d_add(dentry, foundinode);
+ return NULL;
+}
diff --git a/fs/qnx6/qnx6.h b/fs/qnx6/qnx6.h
new file mode 100644
index 000000000000..6c5e02a0b6a8
--- /dev/null
+++ b/fs/qnx6/qnx6.h
@@ -0,0 +1,135 @@
+/*
+ * QNX6 file system, Linux implementation.
+ *
+ * Version : 1.0.0
+ *
+ * History :
+ *
+ * 01-02-2012 by Kai Bankett (chaosman@ontika.net) : first release.
+ * 16-02-2012 page map extension by Al Viro
+ *
+ */
+
+#include <linux/fs.h>
+#include <linux/pagemap.h>
+
+typedef __u16 __bitwise __fs16;
+typedef __u32 __bitwise __fs32;
+typedef __u64 __bitwise __fs64;
+
+#include <linux/qnx6_fs.h>
+
+#ifdef CONFIG_QNX6FS_DEBUG
+#define QNX6DEBUG(X) printk X
+#else
+#define QNX6DEBUG(X) (void) 0
+#endif
+
+struct qnx6_sb_info {
+ struct buffer_head *sb_buf; /* superblock buffer */
+ struct qnx6_super_block *sb; /* our superblock */
+ int s_blks_off; /* blkoffset fs-startpoint */
+ int s_ptrbits; /* indirect pointer bitfield */
+ unsigned long s_mount_opt; /* all mount options */
+ int s_bytesex; /* holds endianess info */
+ struct inode * inodes;
+ struct inode * longfile;
+};
+
+struct qnx6_inode_info {
+ __fs32 di_block_ptr[QNX6_NO_DIRECT_POINTERS];
+ __u8 di_filelevels;
+ __u32 i_dir_start_lookup;
+ struct inode vfs_inode;
+};
+
+extern struct inode *qnx6_iget(struct super_block *sb, unsigned ino);
+extern struct dentry *qnx6_lookup(struct inode *dir, struct dentry *dentry,
+ struct nameidata *nd);
+
+#ifdef CONFIG_QNX6FS_DEBUG
+extern void qnx6_superblock_debug(struct qnx6_super_block *,
+ struct super_block *);
+#endif
+
+extern const struct inode_operations qnx6_dir_inode_operations;
+extern const struct file_operations qnx6_dir_operations;
+
+static inline struct qnx6_sb_info *QNX6_SB(struct super_block *sb)
+{
+ return sb->s_fs_info;
+}
+
+static inline struct qnx6_inode_info *QNX6_I(struct inode *inode)
+{
+ return container_of(inode, struct qnx6_inode_info, vfs_inode);
+}
+
+#define clear_opt(o, opt) (o &= ~(QNX6_MOUNT_##opt))
+#define set_opt(o, opt) (o |= (QNX6_MOUNT_##opt))
+#define test_opt(sb, opt) (QNX6_SB(sb)->s_mount_opt & \
+ QNX6_MOUNT_##opt)
+enum {
+ BYTESEX_LE,
+ BYTESEX_BE,
+};
+
+static inline __u64 fs64_to_cpu(struct qnx6_sb_info *sbi, __fs64 n)
+{
+ if (sbi->s_bytesex == BYTESEX_LE)
+ return le64_to_cpu((__force __le64)n);
+ else
+ return be64_to_cpu((__force __be64)n);
+}
+
+static inline __fs64 cpu_to_fs64(struct qnx6_sb_info *sbi, __u64 n)
+{
+ if (sbi->s_bytesex == BYTESEX_LE)
+ return (__force __fs64)cpu_to_le64(n);
+ else
+ return (__force __fs64)cpu_to_be64(n);
+}
+
+static inline __u32 fs32_to_cpu(struct qnx6_sb_info *sbi, __fs32 n)
+{
+ if (sbi->s_bytesex == BYTESEX_LE)
+ return le32_to_cpu((__force __le32)n);
+ else
+ return be32_to_cpu((__force __be32)n);
+}
+
+static inline __fs32 cpu_to_fs32(struct qnx6_sb_info *sbi, __u32 n)
+{
+ if (sbi->s_bytesex == BYTESEX_LE)
+ return (__force __fs32)cpu_to_le32(n);
+ else
+ return (__force __fs32)cpu_to_be32(n);
+}
+
+static inline __u16 fs16_to_cpu(struct qnx6_sb_info *sbi, __fs16 n)
+{
+ if (sbi->s_bytesex == BYTESEX_LE)
+ return le16_to_cpu((__force __le16)n);
+ else
+ return be16_to_cpu((__force __be16)n);
+}
+
+static inline __fs16 cpu_to_fs16(struct qnx6_sb_info *sbi, __u16 n)
+{
+ if (sbi->s_bytesex == BYTESEX_LE)
+ return (__force __fs16)cpu_to_le16(n);
+ else
+ return (__force __fs16)cpu_to_be16(n);
+}
+
+extern struct qnx6_super_block *qnx6_mmi_fill_super(struct super_block *s,
+ int silent);
+
+static inline void qnx6_put_page(struct page *page)
+{
+ kunmap(page);
+ page_cache_release(page);
+}
+
+extern unsigned qnx6_find_entry(int len, struct inode *dir, const char *name,
+ struct page **res_page);
diff --git a/fs/qnx6/super_mmi.c b/fs/qnx6/super_mmi.c
new file mode 100644
index 000000000000..29c32cba62d6
--- /dev/null
+++ b/fs/qnx6/super_mmi.c
@@ -0,0 +1,150 @@
+/*
+ * QNX6 file system, Linux implementation.
+ *
+ * Version : 1.0.0
+ *
+ * History :
+ *
+ * 01-02-2012 by Kai Bankett (chaosman@ontika.net) : first release.
+ *
+ */
+
+#include <linux/buffer_head.h>
+#include <linux/slab.h>
+#include <linux/crc32.h>
+#include "qnx6.h"
+
+static void qnx6_mmi_copy_sb(struct qnx6_super_block *qsb,
+ struct qnx6_mmi_super_block *sb)
+{
+ qsb->sb_magic = sb->sb_magic;
+ qsb->sb_checksum = sb->sb_checksum;
+ qsb->sb_serial = sb->sb_serial;
+ qsb->sb_blocksize = sb->sb_blocksize;
+ qsb->sb_num_inodes = sb->sb_num_inodes;
+ qsb->sb_free_inodes = sb->sb_free_inodes;
+ qsb->sb_num_blocks = sb->sb_num_blocks;
+ qsb->sb_free_blocks = sb->sb_free_blocks;
+
+ /* the rest of the superblock is the same */
+ memcpy(&qsb->Inode, &sb->Inode, sizeof(sb->Inode));
+ memcpy(&qsb->Bitmap, &sb->Bitmap, sizeof(sb->Bitmap));
+ memcpy(&qsb->Longfile, &sb->Longfile, sizeof(sb->Longfile));
+}
+
+struct qnx6_super_block *qnx6_mmi_fill_super(struct super_block *s, int silent)
+{
+ struct buffer_head *bh1, *bh2 = NULL;
+ struct qnx6_mmi_super_block *sb1, *sb2;
+ struct qnx6_super_block *qsb = NULL;
+ struct qnx6_sb_info *sbi;
+ __u64 offset;
+
+ /* Check the superblock signatures
+ start with the first superblock */
+ bh1 = sb_bread(s, 0);
+ if (!bh1) {
+ printk(KERN_ERR "qnx6: Unable to read first mmi superblock\n");
+ return NULL;
+ }
+ sb1 = (struct qnx6_mmi_super_block *)bh1->b_data;
+ sbi = QNX6_SB(s);
+ if (fs32_to_cpu(sbi, sb1->sb_magic) != QNX6_SUPER_MAGIC) {
+ if (!silent) {
+ printk(KERN_ERR "qnx6: wrong signature (magic) in"
+ " superblock #1.\n");
+ goto out;
+ }
+ }
+
+ /* checksum check - start at byte 8 and end at byte 512 */
+ if (fs32_to_cpu(sbi, sb1->sb_checksum) !=
+ crc32_be(0, (char *)(bh1->b_data + 8), 504)) {
+ printk(KERN_ERR "qnx6: superblock #1 checksum error\n");
+ goto out;
+ }
+
+ /* calculate second superblock blocknumber */
+ offset = fs32_to_cpu(sbi, sb1->sb_num_blocks) + QNX6_SUPERBLOCK_AREA /
+ fs32_to_cpu(sbi, sb1->sb_blocksize);
+
+ /* set new blocksize */
+ if (!sb_set_blocksize(s, fs32_to_cpu(sbi, sb1->sb_blocksize))) {
+ printk(KERN_ERR "qnx6: unable to set blocksize\n");
+ goto out;
+ }
+ /* blocksize invalidates bh - pull it back in */
+ brelse(bh1);
+ bh1 = sb_bread(s, 0);
+ if (!bh1)
+ goto out;
+ sb1 = (struct qnx6_mmi_super_block *)bh1->b_data;
+
+ /* read second superblock */
+ bh2 = sb_bread(s, offset);
+ if (!bh2) {
+ printk(KERN_ERR "qnx6: unable to read the second superblock\n");
+ goto out;
+ }
+ sb2 = (struct qnx6_mmi_super_block *)bh2->b_data;
+ if (fs32_to_cpu(sbi, sb2->sb_magic) != QNX6_SUPER_MAGIC) {
+ if (!silent)
+ printk(KERN_ERR "qnx6: wrong signature (magic) in"
+ " superblock #2.\n");
+ goto out;
+ }
+
+ /* checksum check - start at byte 8 and end at byte 512 */
+ if (fs32_to_cpu(sbi, sb2->sb_checksum)
+ != crc32_be(0, (char *)(bh2->b_data + 8), 504)) {
+ printk(KERN_ERR "qnx6: superblock #1 checksum error\n");
+ goto out;
+ }
+
+ qsb = kmalloc(sizeof(*qsb), GFP_KERNEL);
+ if (!qsb) {
+ printk(KERN_ERR "qnx6: unable to allocate memory.\n");
+ goto out;
+ }
+
+ if (fs64_to_cpu(sbi, sb1->sb_serial) >
+ fs64_to_cpu(sbi, sb2->sb_serial)) {
+ /* superblock #1 active */
+ qnx6_mmi_copy_sb(qsb, sb1);
+#ifdef CONFIG_QNX6FS_DEBUG
+ qnx6_superblock_debug(qsb, s);
+#endif
+ memcpy(bh1->b_data, qsb, sizeof(struct qnx6_super_block));
+
+ sbi->sb_buf = bh1;
+ sbi->sb = (struct qnx6_super_block *)bh1->b_data;
+ brelse(bh2);
+ printk(KERN_INFO "qnx6: superblock #1 active\n");
+ } else {
+ /* superblock #2 active */
+ qnx6_mmi_copy_sb(qsb, sb2);
+#ifdef CONFIG_QNX6FS_DEBUG
+ qnx6_superblock_debug(qsb, s);
+#endif
+ memcpy(bh2->b_data, qsb, sizeof(struct qnx6_super_block));
+
+ sbi->sb_buf = bh2;
+ sbi->sb = (struct qnx6_super_block *)bh2->b_data;
+ brelse(bh1);
+ printk(KERN_INFO "qnx6: superblock #2 active\n");
+ }
+ kfree(qsb);
+
+ /* offset for mmi_fs is just SUPERBLOCK_AREA bytes */
+ sbi->s_blks_off = QNX6_SUPERBLOCK_AREA / s->s_blocksize;
+
+ /* success */
+ return sbi->sb;
+
+out:
+ if (bh1 != NULL)
+ brelse(bh1);
+ if (bh2 != NULL)
+ brelse(bh2);
+ return NULL;
+}