[PATCH] Minix V3 support

This morning I needed to read a Minix V3 filesystem, but unfortunately my
2.6.19 did not support that, and neither did the downloaded 2.6.20rc4.

Fortunately, google told me that Daniel Aragones had already done the work,
patch found at http://www.terra.es/personal2/danarag/

Unfortunaly, looking at the patch was painful to my eyes, so I polished it
a bit before applying.  The resulting kernel boots, and reads the
filesystem it needed to read.

Signed-off-by: Daniel Aragones <danarag@gmail.com>
Signed-off-by: Andries Brouwer <aeb@cwi.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/minix/bitmap.c

@@ -26,14 +26,14 @@ static unsigned long count_free(struct buffer_head *map[], unsigned numblocks, _
 	for (i=0; i<numblocks-1; i++) {
 		if (!(bh=map[i])) 
 			return(0);
-		for (j=0; j<BLOCK_SIZE; j++)
+		for (j=0; j<bh->b_size; j++)
 			sum += nibblemap[bh->b_data[j] & 0xf]
 				+ nibblemap[(bh->b_data[j]>>4) & 0xf];
 	}
 
 	if (numblocks==0 || !(bh=map[numblocks-1]))
 		return(0);
-	i = ((numbits-(numblocks-1)*BLOCK_SIZE*8)/16)*2;
+	i = ((numbits - (numblocks-1) * bh->b_size * 8) / 16) * 2;
 	for (j=0; j<i; j++) {
 		sum += nibblemap[bh->b_data[j] & 0xf]
 			+ nibblemap[(bh->b_data[j]>>4) & 0xf];
@@ -48,28 +48,29 @@ static unsigned long count_free(struct buffer_head *map[], unsigned numblocks, _
 	return(sum);
 }
 
-void minix_free_block(struct inode * inode, int block)
+void minix_free_block(struct inode *inode, unsigned long block)
 {
-	struct super_block * sb = inode->i_sb;
-	struct minix_sb_info * sbi = minix_sb(sb);
-	struct buffer_head * bh;
-	unsigned int bit,zone;
+	struct super_block *sb = inode->i_sb;
+	struct minix_sb_info *sbi = minix_sb(sb);
+	struct buffer_head *bh;
+	int k = sb->s_blocksize_bits + 3;
+	unsigned long bit, zone;
 
 	if (block < sbi->s_firstdatazone || block >= sbi->s_nzones) {
 		printk("Trying to free block not in datazone\n");
 		return;
 	}
 	zone = block - sbi->s_firstdatazone + 1;
-	bit = zone & 8191;
-	zone >>= 13;
+	bit = zone & ((1<<k) - 1);
+	zone >>= k;
 	if (zone >= sbi->s_zmap_blocks) {
 		printk("minix_free_block: nonexistent bitmap buffer\n");
 		return;
 	}
 	bh = sbi->s_zmap[zone];
 	lock_kernel();
-	if (!minix_test_and_clear_bit(bit,bh->b_data))
-		printk("free_block (%s:%d): bit already cleared\n",
+	if (!minix_test_and_clear_bit(bit, bh->b_data))
+		printk("minix_free_block (%s:%lu): bit already cleared\n",
 		       sb->s_id, block);
 	unlock_kernel();
 	mark_buffer_dirty(bh);
@@ -79,6 +80,7 @@ void minix_free_block(struct inode * inode, int block)
 int minix_new_block(struct inode * inode)
 {
 	struct minix_sb_info *sbi = minix_sb(inode->i_sb);
+	int bits_per_zone = 8 * inode->i_sb->s_blocksize;
 	int i;
 
 	for (i = 0; i < sbi->s_zmap_blocks; i++) {
@@ -86,11 +88,12 @@ int minix_new_block(struct inode * inode)
 		int j;
 
 		lock_kernel();
-		if ((j = minix_find_first_zero_bit(bh->b_data, 8192)) < 8192) {
-			minix_set_bit(j,bh->b_data);
+		j = minix_find_first_zero_bit(bh->b_data, bits_per_zone);
+		if (j < bits_per_zone) {
+			minix_set_bit(j, bh->b_data);
 			unlock_kernel();
 			mark_buffer_dirty(bh);
-			j += i*8192 + sbi->s_firstdatazone-1;
+			j += i * bits_per_zone + sbi->s_firstdatazone-1;
 			if (j < sbi->s_firstdatazone || j >= sbi->s_nzones)
 				break;
 			return j;
@@ -137,6 +140,7 @@ minix_V2_raw_inode(struct super_block *sb, ino_t ino, struct buffer_head **bh)
 	int block;
 	struct minix_sb_info *sbi = minix_sb(sb);
 	struct minix2_inode *p;
+	int minix2_inodes_per_block = sb->s_blocksize / sizeof(struct minix2_inode);
 
 	*bh = NULL;
 	if (!ino || ino > sbi->s_ninodes) {
@@ -146,14 +150,14 @@ minix_V2_raw_inode(struct super_block *sb, ino_t ino, struct buffer_head **bh)
 	}
 	ino--;
 	block = 2 + sbi->s_imap_blocks + sbi->s_zmap_blocks +
-		 ino / MINIX2_INODES_PER_BLOCK;
+		 ino / minix2_inodes_per_block;
 	*bh = sb_bread(sb, block);
 	if (!*bh) {
 		printk("Unable to read inode block\n");
 		return NULL;
 	}
 	p = (void *)(*bh)->b_data;
-	return p + ino % MINIX2_INODES_PER_BLOCK;
+	return p + ino % minix2_inodes_per_block;
 }
 
 /* Clear the link count and mode of a deleted inode on disk. */
@@ -185,26 +189,30 @@ static void minix_clear_inode(struct inode *inode)
 
 void minix_free_inode(struct inode * inode)
 {
+	struct super_block *sb = inode->i_sb;
 	struct minix_sb_info *sbi = minix_sb(inode->i_sb);
-	struct buffer_head * bh;
-	unsigned long ino;
+	struct buffer_head *bh;
+	int k = sb->s_blocksize_bits + 3;
+	unsigned long ino, bit;
 
 	ino = inode->i_ino;
 	if (ino < 1 || ino > sbi->s_ninodes) {
 		printk("minix_free_inode: inode 0 or nonexistent inode\n");
 		goto out;
 	}
-	if ((ino >> 13) >= sbi->s_imap_blocks) {
+	bit = ino & ((1<<k) - 1);
+	ino >>= k;
+	if (ino >= sbi->s_imap_blocks) {
 		printk("minix_free_inode: nonexistent imap in superblock\n");
 		goto out;
 	}
 
 	minix_clear_inode(inode);	/* clear on-disk copy */
 
-	bh = sbi->s_imap[ino >> 13];
+	bh = sbi->s_imap[ino];
 	lock_kernel();
-	if (!minix_test_and_clear_bit(ino & 8191, bh->b_data))
-		printk("minix_free_inode: bit %lu already cleared\n", ino);
+	if (!minix_test_and_clear_bit(bit, bh->b_data))
+		printk("minix_free_inode: bit %lu already cleared\n", bit);
 	unlock_kernel();
 	mark_buffer_dirty(bh);
  out:
@@ -217,35 +225,38 @@ struct inode * minix_new_inode(const struct inode * dir, int * error)
 	struct minix_sb_info *sbi = minix_sb(sb);
 	struct inode *inode = new_inode(sb);
 	struct buffer_head * bh;
-	int i,j;
+	int bits_per_zone = 8 * sb->s_blocksize;
+	unsigned long j;
+	int i;
 
 	if (!inode) {
 		*error = -ENOMEM;
 		return NULL;
 	}
-	j = 8192;
+	j = bits_per_zone;
 	bh = NULL;
 	*error = -ENOSPC;
 	lock_kernel();
 	for (i = 0; i < sbi->s_imap_blocks; i++) {
 		bh = sbi->s_imap[i];
-		if ((j = minix_find_first_zero_bit(bh->b_data, 8192)) < 8192)
+		j = minix_find_first_zero_bit(bh->b_data, bits_per_zone);
+		if (j < bits_per_zone)
 			break;
 	}
-	if (!bh || j >= 8192) {
+	if (!bh || j >= bits_per_zone) {
 		unlock_kernel();
 		iput(inode);
 		return NULL;
 	}
-	if (minix_test_and_set_bit(j,bh->b_data)) {	/* shouldn't happen */
-		printk("new_inode: bit already set\n");
+	if (minix_test_and_set_bit(j, bh->b_data)) {	/* shouldn't happen */
 		unlock_kernel();
+		printk("minix_new_inode: bit already set\n");
 		iput(inode);
 		return NULL;
 	}
 	unlock_kernel();
 	mark_buffer_dirty(bh);
-	j += i*8192;
+	j += i * bits_per_zone;
 	if (!j || j > sbi->s_ninodes) {
 		iput(inode);
 		return NULL;

fs/minix/dir.c

@@ -4,6 +4,8 @@
  *  Copyright (C) 1991, 1992 Linus Torvalds
  *
  *  minix directory handling functions
+ *
+ *  Updated to filesystem version 3 by Daniel Aragones
  */
 
 #include "minix.h"
@@ -11,6 +13,7 @@
 #include <linux/smp_lock.h>
 
 typedef struct minix_dir_entry minix_dirent;
+typedef struct minix3_dir_entry minix3_dirent;
 
 static int minix_readdir(struct file *, void *, filldir_t);
 
@@ -89,6 +92,8 @@ static int minix_readdir(struct file * filp, void * dirent, filldir_t filldir)
 	unsigned long npages = dir_pages(inode);
 	struct minix_sb_info *sbi = minix_sb(sb);
 	unsigned chunk_size = sbi->s_dirsize;
+	char *name;
+	__u32 inumber;
 
 	lock_kernel();
 
@@ -105,16 +110,24 @@ static int minix_readdir(struct file * filp, void * dirent, filldir_t filldir)
 		kaddr = (char *)page_address(page);
 		p = kaddr+offset;
 		limit = kaddr + minix_last_byte(inode, n) - chunk_size;
-		for ( ; p <= limit ; p = minix_next_entry(p, sbi)) {
-			minix_dirent *de = (minix_dirent *)p;
-			if (de->inode) {
+		for ( ; p <= limit; p = minix_next_entry(p, sbi)) {
+			if (sbi->s_version == MINIX_V3) {
+				minix3_dirent *de3 = (minix3_dirent *)p;
+				name = de3->name;
+				inumber = de3->inode;
+	 		} else {
+				minix_dirent *de = (minix_dirent *)p;
+				name = de->name;
+				inumber = de->inode;
+			}
+			if (inumber) {
 				int over;
-				unsigned l = strnlen(de->name,sbi->s_namelen);
 
+				unsigned l = strnlen(name, sbi->s_namelen);
 				offset = p - kaddr;
-				over = filldir(dirent, de->name, l,
-						(n<<PAGE_CACHE_SHIFT) | offset,
-						de->inode, DT_UNKNOWN);
+				over = filldir(dirent, name, l,
+					(n << PAGE_CACHE_SHIFT) | offset,
+					inumber, DT_UNKNOWN);
 				if (over) {
 					dir_put_page(page);
 					goto done;
@@ -156,23 +169,34 @@ minix_dirent *minix_find_entry(struct dentry *dentry, struct page **res_page)
 	unsigned long n;
 	unsigned long npages = dir_pages(dir);
 	struct page *page = NULL;
-	struct minix_dir_entry *de;
+	char *p;
 
+	char *namx;
+	__u32 inumber;
 	*res_page = NULL;
 
 	for (n = 0; n < npages; n++) {
-		char *kaddr;
+		char *kaddr, *limit;
+
 		page = dir_get_page(dir, n);
 		if (IS_ERR(page))
 			continue;
 
 		kaddr = (char*)page_address(page);
-		de = (struct minix_dir_entry *) kaddr;
-		kaddr += minix_last_byte(dir, n) - sbi->s_dirsize;
-		for ( ; (char *) de <= kaddr ; de = minix_next_entry(de,sbi)) {
-			if (!de->inode)
+		limit = kaddr + minix_last_byte(dir, n) - sbi->s_dirsize;
+		for (p = kaddr; p <= limit; p = minix_next_entry(p, sbi)) {
+			if (sbi->s_version == MINIX_V3) {
+				minix3_dirent *de3 = (minix3_dirent *)p;
+				namx = de3->name;
+				inumber = de3->inode;
+ 			} else {
+				minix_dirent *de = (minix_dirent *)p;
+				namx = de->name;
+				inumber = de->inode;
+			}
+			if (!inumber)
 				continue;
-			if (namecompare(namelen,sbi->s_namelen,name,de->name))
+			if (namecompare(namelen, sbi->s_namelen, name, namx))
 				goto found;
 		}
 		dir_put_page(page);
@@ -181,7 +205,7 @@ minix_dirent *minix_find_entry(struct dentry *dentry, struct page **res_page)
 
 found:
 	*res_page = page;
-	return de;
+	return (minix_dirent *)p;
 }
 
 int minix_add_link(struct dentry *dentry, struct inode *inode)
@@ -192,12 +216,15 @@ int minix_add_link(struct dentry *dentry, struct inode *inode)
 	struct super_block * sb = dir->i_sb;
 	struct minix_sb_info * sbi = minix_sb(sb);
 	struct page *page = NULL;
-	struct minix_dir_entry * de;
 	unsigned long npages = dir_pages(dir);
 	unsigned long n;
-	char *kaddr;
+	char *kaddr, *p;
+	minix_dirent *de;
+	minix3_dirent *de3;
 	unsigned from, to;
 	int err;
+	char *namx = NULL;
+	__u32 inumber;
 
 	/*
 	 * We take care of directory expansion in the same loop
@@ -205,7 +232,7 @@ int minix_add_link(struct dentry *dentry, struct inode *inode)
 	 * to protect that region.
 	 */
 	for (n = 0; n <= npages; n++) {
-		char *dir_end;
+		char *limit, *dir_end;
 
 		page = dir_get_page(dir, n);
 		err = PTR_ERR(page);
@@ -214,20 +241,30 @@ int minix_add_link(struct dentry *dentry, struct inode *inode)
 		lock_page(page);
 		kaddr = (char*)page_address(page);
 		dir_end = kaddr + minix_last_byte(dir, n);
-		de = (minix_dirent *)kaddr;
-		kaddr += PAGE_CACHE_SIZE - sbi->s_dirsize;
-		while ((char *)de <= kaddr) {
-			if ((char *)de == dir_end) {
+		limit = kaddr + PAGE_CACHE_SIZE - sbi->s_dirsize;
+		for (p = kaddr; p <= limit; p = minix_next_entry(p, sbi)) {
+			de = (minix_dirent *)p;
+			de3 = (minix3_dirent *)p;
+			if (sbi->s_version == MINIX_V3) {
+				namx = de3->name;
+				inumber = de3->inode;
+		 	} else {
+  				namx = de->name;
+				inumber = de->inode;
+			}
+			if (p == dir_end) {
 				/* We hit i_size */
-				de->inode = 0;
+				if (sbi->s_version == MINIX_V3)
+					de3->inode = 0;
+		 		else
+					de->inode = 0;
 				goto got_it;
 			}
-			if (!de->inode)
+			if (!inumber)
 				goto got_it;
 			err = -EEXIST;
-			if (namecompare(namelen,sbi->s_namelen,name,de->name))
+			if (namecompare(namelen, sbi->s_namelen, name, namx))
 				goto out_unlock;
-			de = minix_next_entry(de, sbi);
 		}
 		unlock_page(page);
 		dir_put_page(page);
@@ -236,14 +273,19 @@ int minix_add_link(struct dentry *dentry, struct inode *inode)
 	return -EINVAL;
 
 got_it:
-	from = (char*)de - (char*)page_address(page);
+	from = p - (char*)page_address(page);
 	to = from + sbi->s_dirsize;
 	err = page->mapping->a_ops->prepare_write(NULL, page, from, to);
 	if (err)
 		goto out_unlock;
-	memcpy (de->name, name, namelen);
-	memset (de->name + namelen, 0, sbi->s_dirsize - namelen - 2);
-	de->inode = inode->i_ino;
+	memcpy (namx, name, namelen);
+	if (sbi->s_version == MINIX_V3) {
+		memset (namx + namelen, 0, sbi->s_dirsize - namelen - 4);
+		de3->inode = inode->i_ino;
+	} else {
+		memset (namx + namelen, 0, sbi->s_dirsize - namelen - 2);
+		de->inode = inode->i_ino;
+	}
 	err = dir_commit_chunk(page, from, to);
 	dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
 	mark_inode_dirty(dir);
@@ -283,8 +325,7 @@ int minix_make_empty(struct inode *inode, struct inode *dir)
 {
 	struct address_space *mapping = inode->i_mapping;
 	struct page *page = grab_cache_page(mapping, 0);
-	struct minix_sb_info * sbi = minix_sb(inode->i_sb);
-	struct minix_dir_entry * de;
+	struct minix_sb_info *sbi = minix_sb(inode->i_sb);
 	char *kaddr;
 	int err;
 
@@ -299,12 +340,23 @@ int minix_make_empty(struct inode *inode, struct inode *dir)
 	kaddr = kmap_atomic(page, KM_USER0);
 	memset(kaddr, 0, PAGE_CACHE_SIZE);
 
-	de = (struct minix_dir_entry *)kaddr;
-	de->inode = inode->i_ino;
-	strcpy(de->name,".");
-	de = minix_next_entry(de, sbi);
-	de->inode = dir->i_ino;
-	strcpy(de->name,"..");
+	if (sbi->s_version == MINIX_V3) {
+		minix3_dirent *de3 = (minix3_dirent *)kaddr;
+
+		de3->inode = inode->i_ino;
+		strcpy(de3->name, ".");
+		de3 = minix_next_entry(de3, sbi);
+		de3->inode = dir->i_ino;
+		strcpy(de3->name, "..");
+	} else {
+		minix_dirent *de = (minix_dirent *)kaddr;
+
+		de->inode = inode->i_ino;
+		strcpy(de->name, ".");
+		de = minix_next_entry(de, sbi);
+		de->inode = dir->i_ino;
+		strcpy(de->name, "..");
+	}
 	kunmap_atomic(kaddr, KM_USER0);
 
 	err = dir_commit_chunk(page, 0, 2 * sbi->s_dirsize);
@@ -321,33 +373,41 @@ int minix_empty_dir(struct inode * inode)
 	struct page *page = NULL;
 	unsigned long i, npages = dir_pages(inode);
 	struct minix_sb_info *sbi = minix_sb(inode->i_sb);
+	char *name;
+	__u32 inumber;
 
 	for (i = 0; i < npages; i++) {
-		char *kaddr;
-		minix_dirent * de;
-		page = dir_get_page(inode, i);
+		char *p, *kaddr, *limit;
 
+		page = dir_get_page(inode, i);
 		if (IS_ERR(page))
 			continue;
 
 		kaddr = (char *)page_address(page);
-		de = (minix_dirent *)kaddr;
-		kaddr += minix_last_byte(inode, i) - sbi->s_dirsize;
+		limit = kaddr + minix_last_byte(inode, i) - sbi->s_dirsize;
+		for (p = kaddr; p <= limit; p = minix_next_entry(p, sbi)) {
+			if (sbi->s_version == MINIX_V3) {
+				minix3_dirent *de3 = (minix3_dirent *)p;
+				name = de3->name;
+				inumber = de3->inode;
+			} else {
+				minix_dirent *de = (minix_dirent *)p;
+				name = de->name;
+				inumber = de->inode;
+			}
 
-		while ((char *)de <= kaddr) {
-			if (de->inode != 0) {
+			if (inumber != 0) {
 				/* check for . and .. */
-				if (de->name[0] != '.')
+				if (name[0] != '.')
 					goto not_empty;
-				if (!de->name[1]) {
-					if (de->inode != inode->i_ino)
+				if (!name[1]) {
+					if (inumber != inode->i_ino)
 						goto not_empty;
-				} else if (de->name[1] != '.')
+				} else if (name[1] != '.')
 					goto not_empty;
-				else if (de->name[2])
+				else if (name[2])
 					goto not_empty;
 			}
-			de = minix_next_entry(de, sbi);
 		}
 		dir_put_page(page);
 	}

fs/minix/inode.c

@@ -7,6 +7,7 @@
  *	Minix V2 fs support.
  *
  *  Modified for 680x0 by Andreas Schwab
+ *  Updated to filesystem version 3 by Daniel Aragones
  */
 
 #include <linux/module.h>
@@ -36,7 +37,8 @@ static void minix_put_super(struct super_block *sb)
 	struct minix_sb_info *sbi = minix_sb(sb);
 
 	if (!(sb->s_flags & MS_RDONLY)) {
-		sbi->s_ms->s_state = sbi->s_mount_state;
+		if (sbi->s_version != MINIX_V3)	 /* s_state is now out from V3 sb */
+			sbi->s_ms->s_state = sbi->s_mount_state;
 		mark_buffer_dirty(sbi->s_sbh);
 	}
 	for (i = 0; i < sbi->s_imap_blocks; i++)
@@ -117,12 +119,17 @@ static int minix_remount (struct super_block * sb, int * flags, char * data)
 		    !(sbi->s_mount_state & MINIX_VALID_FS))
 			return 0;
 		/* Mounting a rw partition read-only. */
-		ms->s_state = sbi->s_mount_state;
+		if (sbi->s_version != MINIX_V3)
+			ms->s_state = sbi->s_mount_state;
 		mark_buffer_dirty(sbi->s_sbh);
 	} else {
 	  	/* Mount a partition which is read-only, read-write. */
-		sbi->s_mount_state = ms->s_state;
-		ms->s_state &= ~MINIX_VALID_FS;
+		if (sbi->s_version != MINIX_V3) {
+			sbi->s_mount_state = ms->s_state;
+			ms->s_state &= ~MINIX_VALID_FS;
+		} else {
+			sbi->s_mount_state = MINIX_VALID_FS;
+		}
 		mark_buffer_dirty(sbi->s_sbh);
 
 		if (!(sbi->s_mount_state & MINIX_VALID_FS))
@@ -140,7 +147,8 @@ static int minix_fill_super(struct super_block *s, void *data, int silent)
 	struct buffer_head *bh;
 	struct buffer_head **map;
 	struct minix_super_block *ms;
-	int i, block;
+	struct minix3_super_block *m3s = NULL;
+	unsigned long i, block;
 	struct inode *root_inode;
 	struct minix_sb_info *sbi;
 
@@ -192,6 +200,22 @@ static int minix_fill_super(struct super_block *s, void *data, int silent)
 		sbi->s_dirsize = 32;
 		sbi->s_namelen = 30;
 		sbi->s_link_max = MINIX2_LINK_MAX;
+	} else if ( *(__u16 *)(bh->b_data + 24) == MINIX3_SUPER_MAGIC) {
+		m3s = (struct minix3_super_block *) bh->b_data;
+		s->s_magic = m3s->s_magic;
+		sbi->s_imap_blocks = m3s->s_imap_blocks;
+		sbi->s_zmap_blocks = m3s->s_zmap_blocks;
+		sbi->s_firstdatazone = m3s->s_firstdatazone;
+		sbi->s_log_zone_size = m3s->s_log_zone_size;
+		sbi->s_max_size = m3s->s_max_size;
+		sbi->s_ninodes = m3s->s_ninodes;
+		sbi->s_nzones = m3s->s_zones;
+		sbi->s_dirsize = 64;
+		sbi->s_namelen = 60;
+		sbi->s_version = MINIX_V3;
+		sbi->s_link_max = MINIX2_LINK_MAX;
+		sbi->s_mount_state = MINIX_VALID_FS;
+		sb_set_blocksize(s, m3s->s_blocksize);
 	} else
 		goto out_no_fs;
 
@@ -236,7 +260,8 @@ static int minix_fill_super(struct super_block *s, void *data, int silent)
 		s->s_root->d_op = &minix_dentry_operations;
 
 	if (!(s->s_flags & MS_RDONLY)) {
-		ms->s_state &= ~MINIX_VALID_FS;
+		if (sbi->s_version != MINIX_V3) /* s_state is now out from V3 sb */
+			ms->s_state &= ~MINIX_VALID_FS;
 		mark_buffer_dirty(bh);
 	}
 	if (!(sbi->s_mount_state & MINIX_VALID_FS))
@@ -278,8 +303,8 @@ out_illegal_sb:
 
 out_no_fs:
 	if (!silent)
-		printk("VFS: Can't find a Minix or Minix V2 filesystem "
-			"on device %s\n", s->s_id);
+		printk("VFS: Can't find a Minix filesystem V1 | V2 | V3 "
+		       "on device %s.\n", s->s_id);
 out_release:
 	brelse(bh);
 	goto out;
@@ -537,12 +562,14 @@ int minix_sync_inode(struct inode * inode)
 
 int minix_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
 {
+	struct inode *dir = dentry->d_parent->d_inode;
+	struct super_block *sb = dir->i_sb;
 	generic_fillattr(dentry->d_inode, stat);
 	if (INODE_VERSION(dentry->d_inode) == MINIX_V1)
-		stat->blocks = (BLOCK_SIZE / 512) * V1_minix_blocks(stat->size);
+		stat->blocks = (BLOCK_SIZE / 512) * V1_minix_blocks(stat->size, sb);
 	else
-		stat->blocks = (BLOCK_SIZE / 512) * V2_minix_blocks(stat->size);
-	stat->blksize = BLOCK_SIZE;
+		stat->blocks = (sb->s_blocksize / 512) * V2_minix_blocks(stat->size, sb);
+	stat->blksize = sb->s_blocksize;
 	return 0;
 }
 

fs/minix/itree_common.c

@@ -23,7 +23,7 @@ static inline int verify_chain(Indirect *from, Indirect *to)
 
 static inline block_t *block_end(struct buffer_head *bh)
 {
-	return (block_t *)((char*)bh->b_data + BLOCK_SIZE);
+	return (block_t *)((char*)bh->b_data + bh->b_size);
 }
 
 static inline Indirect *get_branch(struct inode *inode,
@@ -85,7 +85,7 @@ static int alloc_branch(struct inode *inode,
 		branch[n].key = cpu_to_block(nr);
 		bh = sb_getblk(inode->i_sb, parent);
 		lock_buffer(bh);
-		memset(bh->b_data, 0, BLOCK_SIZE);
+		memset(bh->b_data, 0, bh->b_size);
 		branch[n].bh = bh;
 		branch[n].p = (block_t*) bh->b_data + offsets[n];
 		*branch[n].p = branch[n].key;
@@ -292,6 +292,7 @@ static void free_branches(struct inode *inode, block_t *p, block_t *q, int depth
 
 static inline void truncate (struct inode * inode)
 {
+	struct super_block *sb = inode->i_sb;
 	block_t *idata = i_data(inode);
 	int offsets[DEPTH];
 	Indirect chain[DEPTH];
@@ -301,7 +302,7 @@ static inline void truncate (struct inode * inode)
 	int first_whole;
 	long iblock;
 
-	iblock = (inode->i_size + BLOCK_SIZE-1) >> 10;
+	iblock = (inode->i_size + sb->s_blocksize -1) >> sb->s_blocksize_bits;
 	block_truncate_page(inode->i_mapping, inode->i_size, get_block);
 
 	n = block_to_path(inode, iblock, offsets);
@@ -346,15 +347,16 @@ do_indirects:
 	mark_inode_dirty(inode);
 }
 
-static inline unsigned nblocks(loff_t size)
+static inline unsigned nblocks(loff_t size, struct super_block *sb)
 {
+	int k = sb->s_blocksize_bits - 10;
 	unsigned blocks, res, direct = DIRECT, i = DEPTH;
-	blocks = (size + BLOCK_SIZE - 1) >> BLOCK_SIZE_BITS;
+	blocks = (size + sb->s_blocksize - 1) >> (BLOCK_SIZE_BITS + k);
 	res = blocks;
 	while (--i && blocks > direct) {
 		blocks -= direct;
-		blocks += BLOCK_SIZE/sizeof(block_t) - 1;
-		blocks /= BLOCK_SIZE/sizeof(block_t);
+		blocks += sb->s_blocksize/sizeof(block_t) - 1;
+		blocks /= sb->s_blocksize/sizeof(block_t);
 		res += blocks;
 		direct = 1;
 	}

fs/minix/itree_v1.c

@@ -55,7 +55,7 @@ void V1_minix_truncate(struct inode * inode)
 	truncate(inode);
 }
 
-unsigned V1_minix_blocks(loff_t size)
+unsigned V1_minix_blocks(loff_t size, struct super_block *sb)
 {
-	return nblocks(size);
+	return nblocks(size, sb);
 }

fs/minix/itree_v2.c

@@ -23,10 +23,11 @@ static inline block_t *i_data(struct inode *inode)
 static int block_to_path(struct inode * inode, long block, int offsets[DEPTH])
 {
 	int n = 0;
+	struct super_block *sb = inode->i_sb;
 
 	if (block < 0) {
 		printk("minix_bmap: block<0\n");
-	} else if (block >= (minix_sb(inode->i_sb)->s_max_size/BLOCK_SIZE)) {
+	} else if (block >= (minix_sb(inode->i_sb)->s_max_size/sb->s_blocksize)) {
 		printk("minix_bmap: block>big\n");
 	} else if (block < 7) {
 		offsets[n++] = block;
@@ -60,7 +61,7 @@ void V2_minix_truncate(struct inode * inode)
 	truncate(inode);
 }
 
-unsigned V2_minix_blocks(loff_t size)
+unsigned V2_minix_blocks(loff_t size, struct super_block *sb)
 {
-	return nblocks(size);
+	return nblocks(size, sb);
 }

fs/minix/minix.h

@@ -7,11 +7,10 @@
  * truncated. Else they will be disallowed (ENAMETOOLONG).
  */
 #define NO_TRUNCATE 1
-
 #define INODE_VERSION(inode)	minix_sb(inode->i_sb)->s_version
-
 #define MINIX_V1		0x0001		/* original minix fs */
 #define MINIX_V2		0x0002		/* minix V2 fs */
+#define MINIX_V3		0x0003		/* minix V3 fs */
 
 /*
  * minix fs inode data in memory
@@ -52,12 +51,10 @@ extern struct inode * minix_new_inode(const struct inode * dir, int * error);
 extern void minix_free_inode(struct inode * inode);
 extern unsigned long minix_count_free_inodes(struct minix_sb_info *sbi);
 extern int minix_new_block(struct inode * inode);
-extern void minix_free_block(struct inode * inode, int block);
+extern void minix_free_block(struct inode *inode, unsigned long block);
 extern unsigned long minix_count_free_blocks(struct minix_sb_info *sbi);
-
 extern int minix_getattr(struct vfsmount *, struct dentry *, struct kstat *);
 
-extern void V2_minix_truncate(struct inode *);
 extern void V1_minix_truncate(struct inode *);
 extern void V2_minix_truncate(struct inode *);
 extern void minix_truncate(struct inode *);
@@ -65,8 +62,8 @@ extern int minix_sync_inode(struct inode *);
 extern void minix_set_inode(struct inode *, dev_t);
 extern int V1_minix_get_block(struct inode *, long, struct buffer_head *, int);
 extern int V2_minix_get_block(struct inode *, long, struct buffer_head *, int);
-extern unsigned V1_minix_blocks(loff_t);
-extern unsigned V2_minix_blocks(loff_t);
+extern unsigned V1_minix_blocks(loff_t, struct super_block *);
+extern unsigned V2_minix_blocks(loff_t, struct super_block *);
 
 extern struct minix_dir_entry *minix_find_entry(struct dentry*, struct page**);
 extern int minix_add_link(struct dentry*, struct inode*);
@@ -76,7 +73,6 @@ extern int minix_empty_dir(struct inode*);
 extern void minix_set_link(struct minix_dir_entry*, struct page*, struct inode*);
 extern struct minix_dir_entry *minix_dotdot(struct inode*, struct page**);
 extern ino_t minix_inode_by_name(struct dentry*);
-
 extern int minix_sync_file(struct file *, struct dentry *, int);
 
 extern struct inode_operations minix_file_inode_operations;

include/linux/magic.h

@@ -18,6 +18,7 @@
 #define MINIX_SUPER_MAGIC2	0x138F		/* minix fs, 30 char names */
 #define MINIX2_SUPER_MAGIC	0x2468		/* minix V2 fs */
 #define MINIX2_SUPER_MAGIC2	0x2478		/* minix V2 fs, 30 char names */
+#define MINIX3_SUPER_MAGIC	0x4d5a		/* minix V3 fs */
 
 #define MSDOS_SUPER_MAGIC	0x4d44		/* MD */
 #define NCP_SUPER_MAGIC		0x564c		/* Guess, what 0x564c is :-) */

include/linux/minix_fs.h

@@ -25,7 +25,6 @@
 #define MINIX_ERROR_FS		0x0002		/* fs has errors. */
 
 #define MINIX_INODES_PER_BLOCK ((BLOCK_SIZE)/(sizeof (struct minix_inode)))
-#define MINIX2_INODES_PER_BLOCK ((BLOCK_SIZE)/(sizeof (struct minix2_inode)))
 
 /*
  * This is the original minix inode layout on disk.
@@ -75,9 +74,33 @@ struct minix_super_block {
 	__u32 s_zones;
 };
 
+/*
+ * V3 minix super-block data on disk
+ */
+struct minix3_super_block {
+	__u16 s_ninodes;
+	__u16 s_nzones;
+	__u16 s_pad0;
+	__u16 s_imap_blocks;
+	__u16 s_zmap_blocks;
+	__u16 s_firstdatazone;
+	__u16 s_log_zone_size;
+	__u16 s_pad1;
+	__u32 s_max_size;
+	__u32 s_zones;
+	__u16 s_magic;
+	__u16 s_pad2;
+	__u16 s_blocksize;
+	__u8  s_disk_version;
+};
+
 struct minix_dir_entry {
 	__u16 inode;
 	char name[0];
 };
 
+struct minix3_dir_entry {
+	__u32 inode;
+	char name[0];
+};
 #endif