From: Brian Gerst <bgerst@didntduck.org>
To: Linux kernel mailing list <linux-kernel@vger.kernel.org>
Cc: Alexander Viro <viro@math.psu.edu>,
Linus Torvalds <torvalds@transmeta.com>
Subject: [PATCH] struct superblock cleanup - minixfs
Date: Mon, 11 Mar 2002 17:59:28 -0500 [thread overview]
Message-ID: <3C8D36D0.C43162A2@didntduck.org> (raw)
[-- Attachment #1: Type: text/plain, Size: 403 bytes --]
These two patches are the start of cleaning up the union of
filesystem-specific structures in struct super_block. The goal is to
remove dependence on filesystem headers in fs.h. The first patch
abstracts the access to the minix_sb_info structure through the function
minix_sb(). The second patch switches to using kmalloc to allocate the
structure.
Patches are against 2.5.6.
--
Brian Gerst
[-- Attachment #2: sb-minix-a1 --]
[-- Type: text/plain, Size: 14709 bytes --]
diff -urN -X scripts/dontdiff linux-2.5.6/fs/minix/bitmap.c linux/fs/minix/bitmap.c
--- linux-2.5.6/fs/minix/bitmap.c Wed Feb 6 11:47:05 2002
+++ linux/fs/minix/bitmap.c Thu Mar 7 09:46:20 2002
@@ -52,6 +52,7 @@
void minix_free_block(struct inode * inode, int block)
{
struct super_block * sb = inode->i_sb;
+ struct minix_sb_info * sbi = minix_sb(sb);
struct buffer_head * bh;
unsigned int bit,zone;
@@ -59,19 +60,19 @@
printk("trying to free block on nonexistent device\n");
return;
}
- if (block < sb->u.minix_sb.s_firstdatazone ||
- block >= sb->u.minix_sb.s_nzones) {
+ if (block < sbi->s_firstdatazone ||
+ block >= sbi->s_nzones) {
printk("trying to free block not in datazone\n");
return;
}
- zone = block - sb->u.minix_sb.s_firstdatazone + 1;
+ zone = block - sbi->s_firstdatazone + 1;
bit = zone & 8191;
zone >>= 13;
- if (zone >= sb->u.minix_sb.s_zmap_blocks) {
+ if (zone >= sbi->s_zmap_blocks) {
printk("minix_free_block: nonexistent bitmap buffer\n");
return;
}
- bh = sb->u.minix_sb.s_zmap[zone];
+ bh = sbi->s_zmap[zone];
if (!minix_test_and_clear_bit(bit,bh->b_data))
printk("free_block (%s:%d): bit already cleared\n",
sb->s_id, block);
@@ -82,6 +83,7 @@
int minix_new_block(struct inode * inode)
{
struct super_block * sb = inode->i_sb;
+ struct minix_sb_info * sbi = minix_sb(sb);
struct buffer_head * bh;
int i,j;
@@ -92,8 +94,8 @@
repeat:
j = 8192;
bh = NULL;
- for (i = 0; i < sb->u.minix_sb.s_zmap_blocks; i++) {
- bh = sb->u.minix_sb.s_zmap[i];
+ for (i = 0; i < sbi->s_zmap_blocks; i++) {
+ bh = sbi->s_zmap[i];
if ((j = minix_find_first_zero_bit(bh->b_data, 8192)) < 8192)
break;
}
@@ -104,25 +106,26 @@
goto repeat;
}
mark_buffer_dirty(bh);
- j += i*8192 + sb->u.minix_sb.s_firstdatazone-1;
- if (j < sb->u.minix_sb.s_firstdatazone ||
- j >= sb->u.minix_sb.s_nzones)
+ j += i*8192 + sbi->s_firstdatazone-1;
+ if (j < sbi->s_firstdatazone ||
+ j >= sbi->s_nzones)
return 0;
return j;
}
unsigned long minix_count_free_blocks(struct super_block *sb)
{
- return (count_free(sb->u.minix_sb.s_zmap, sb->u.minix_sb.s_zmap_blocks,
- sb->u.minix_sb.s_nzones - sb->u.minix_sb.s_firstdatazone + 1)
- << sb->u.minix_sb.s_log_zone_size);
+ struct minix_sb_info *sbi = minix_sb(sb);
+ return (count_free(sbi->s_zmap, sbi->s_zmap_blocks,
+ sbi->s_nzones - sbi->s_firstdatazone + 1)
+ << sbi->s_log_zone_size);
}
struct minix_inode *
minix_V1_raw_inode(struct super_block *sb, ino_t ino, struct buffer_head **bh)
{
int block;
- struct minix_sb_info *sbi = &sb->u.minix_sb;
+ struct minix_sb_info *sbi = minix_sb(sb);
struct minix_inode *p;
if (!ino || ino > sbi->s_ninodes) {
@@ -146,7 +149,7 @@
minix_V2_raw_inode(struct super_block *sb, ino_t ino, struct buffer_head **bh)
{
int block;
- struct minix_sb_info *sbi = &sb->u.minix_sb;
+ struct minix_sb_info *sbi = minix_sb(sb);
struct minix2_inode *p;
*bh = NULL;
@@ -198,17 +201,17 @@
struct buffer_head * bh;
unsigned long ino;
- if (inode->i_ino < 1 || inode->i_ino > inode->i_sb->u.minix_sb.s_ninodes) {
+ if (inode->i_ino < 1 || inode->i_ino > minix_sb(inode->i_sb)->s_ninodes) {
printk("free_inode: inode 0 or nonexistent inode\n");
return;
}
ino = inode->i_ino;
- if ((ino >> 13) >= inode->i_sb->u.minix_sb.s_imap_blocks) {
+ if ((ino >> 13) >= minix_sb(inode->i_sb)->s_imap_blocks) {
printk("free_inode: nonexistent imap in superblock\n");
return;
}
- bh = inode->i_sb->u.minix_sb.s_imap[ino >> 13];
+ bh = minix_sb(inode->i_sb)->s_imap[ino >> 13];
minix_clear_inode(inode);
clear_inode(inode);
if (!minix_test_and_clear_bit(ino & 8191, bh->b_data))
@@ -233,8 +236,8 @@
bh = NULL;
*error = -ENOSPC;
lock_super(sb);
- for (i = 0; i < sb->u.minix_sb.s_imap_blocks; i++) {
- bh = inode->i_sb->u.minix_sb.s_imap[i];
+ for (i = 0; i < minix_sb(sb)->s_imap_blocks; i++) {
+ bh = minix_sb(inode->i_sb)->s_imap[i];
if ((j = minix_find_first_zero_bit(bh->b_data, 8192)) < 8192)
break;
}
@@ -251,7 +254,7 @@
}
mark_buffer_dirty(bh);
j += i*8192;
- if (!j || j > inode->i_sb->u.minix_sb.s_ninodes) {
+ if (!j || j > minix_sb(inode->i_sb)->s_ninodes) {
iput(inode);
unlock_super(sb);
return NULL;
@@ -272,6 +275,6 @@
unsigned long minix_count_free_inodes(struct super_block *sb)
{
- return count_free(sb->u.minix_sb.s_imap, sb->u.minix_sb.s_imap_blocks,
- sb->u.minix_sb.s_ninodes + 1);
+ return count_free(minix_sb(sb)->s_imap, minix_sb(sb)->s_imap_blocks,
+ minix_sb(sb)->s_ninodes + 1);
}
diff -urN -X scripts/dontdiff linux-2.5.6/fs/minix/dir.c linux/fs/minix/dir.c
--- linux-2.5.6/fs/minix/dir.c Wed Feb 20 01:47:36 2002
+++ linux/fs/minix/dir.c Thu Mar 7 09:36:53 2002
@@ -77,7 +77,7 @@
unsigned offset = pos & ~PAGE_CACHE_MASK;
unsigned long n = pos >> PAGE_CACHE_SHIFT;
unsigned long npages = dir_pages(inode);
- struct minix_sb_info *sbi = &sb->u.minix_sb;
+ struct minix_sb_info *sbi = minix_sb(sb);
unsigned chunk_size = sbi->s_dirsize;
pos = (pos + chunk_size-1) & ~(chunk_size-1);
@@ -140,7 +140,7 @@
int namelen = dentry->d_name.len;
struct inode * dir = dentry->d_parent->d_inode;
struct super_block * sb = dir->i_sb;
- struct minix_sb_info * sbi = &sb->u.minix_sb;
+ struct minix_sb_info * sbi = minix_sb(sb);
unsigned long n;
unsigned long npages = dir_pages(dir);
struct page *page = NULL;
@@ -178,7 +178,7 @@
const char * name = dentry->d_name.name;
int namelen = dentry->d_name.len;
struct super_block * sb = dir->i_sb;
- struct minix_sb_info * sbi = &sb->u.minix_sb;
+ struct minix_sb_info * sbi = minix_sb(sb);
struct page *page = NULL;
struct minix_dir_entry * de;
unsigned long npages = dir_pages(dir);
@@ -236,7 +236,7 @@
struct inode *inode = (struct inode*)mapping->host;
char *kaddr = (char*)page_address(page);
unsigned from = (char*)de - kaddr;
- unsigned to = from + inode->i_sb->u.minix_sb.s_dirsize;
+ unsigned to = from + minix_sb(inode->i_sb)->s_dirsize;
int err;
lock_page(page);
@@ -256,7 +256,7 @@
{
struct address_space *mapping = inode->i_mapping;
struct page *page = grab_cache_page(mapping, 0);
- struct minix_sb_info * sbi = &inode->i_sb->u.minix_sb;
+ struct minix_sb_info * sbi = minix_sb(inode->i_sb);
struct minix_dir_entry * de;
char *base;
int err;
@@ -291,7 +291,7 @@
{
struct page *page = NULL;
unsigned long i, npages = dir_pages(inode);
- struct minix_sb_info *sbi = &inode->i_sb->u.minix_sb;
+ struct minix_sb_info *sbi = minix_sb(inode->i_sb);
for (i = 0; i < npages; i++) {
char *kaddr;
@@ -334,7 +334,7 @@
struct inode *inode)
{
struct inode *dir = (struct inode*)page->mapping->host;
- struct minix_sb_info *sbi = &dir->i_sb->u.minix_sb;
+ struct minix_sb_info *sbi = minix_sb(dir->i_sb);
unsigned from = (char *)de-(char*)page_address(page);
unsigned to = from + sbi->s_dirsize;
int err;
@@ -354,7 +354,7 @@
struct minix_dir_entry * minix_dotdot (struct inode *dir, struct page **p)
{
struct page *page = dir_get_page(dir, 0);
- struct minix_sb_info *sbi = &dir->i_sb->u.minix_sb;
+ struct minix_sb_info *sbi = minix_sb(dir->i_sb);
struct minix_dir_entry *de = NULL;
if (!IS_ERR(page)) {
diff -urN -X scripts/dontdiff linux-2.5.6/fs/minix/inode.c linux/fs/minix/inode.c
--- linux-2.5.6/fs/minix/inode.c Wed Feb 20 01:47:36 2002
+++ linux/fs/minix/inode.c Thu Mar 7 09:39:46 2002
@@ -36,7 +36,7 @@
static void minix_commit_super(struct super_block * sb)
{
- mark_buffer_dirty(sb->u.minix_sb.s_sbh);
+ mark_buffer_dirty(minix_sb(sb)->s_sbh);
sb->s_dirt = 0;
}
@@ -45,7 +45,7 @@
struct minix_super_block * ms;
if (!(sb->s_flags & MS_RDONLY)) {
- ms = sb->u.minix_sb.s_ms;
+ ms = minix_sb(sb)->s_ms;
if (ms->s_state & MINIX_VALID_FS)
ms->s_state &= ~MINIX_VALID_FS;
@@ -58,17 +58,18 @@
static void minix_put_super(struct super_block *sb)
{
int i;
+ struct minix_sb_info *sbi = minix_sb(sb);
if (!(sb->s_flags & MS_RDONLY)) {
- sb->u.minix_sb.s_ms->s_state = sb->u.minix_sb.s_mount_state;
- mark_buffer_dirty(sb->u.minix_sb.s_sbh);
+ sbi->s_ms->s_state = sbi->s_mount_state;
+ mark_buffer_dirty(sbi->s_sbh);
}
- for (i = 0; i < sb->u.minix_sb.s_imap_blocks; i++)
- brelse(sb->u.minix_sb.s_imap[i]);
- for (i = 0; i < sb->u.minix_sb.s_zmap_blocks; i++)
- brelse(sb->u.minix_sb.s_zmap[i]);
- brelse (sb->u.minix_sb.s_sbh);
- kfree(sb->u.minix_sb.s_imap);
+ for (i = 0; i < sbi->s_imap_blocks; i++)
+ brelse(sbi->s_imap[i]);
+ for (i = 0; i < sbi->s_zmap_blocks; i++)
+ brelse(sbi->s_zmap[i]);
+ brelse (sbi->s_sbh);
+ kfree(sbi->s_imap);
return;
}
@@ -129,32 +130,33 @@
static int minix_remount (struct super_block * sb, int * flags, char * data)
{
+ struct minix_sb_info * sbi = minix_sb(sb);
struct minix_super_block * ms;
- ms = sb->u.minix_sb.s_ms;
+ ms = sbi->s_ms;
if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
return 0;
if (*flags & MS_RDONLY) {
if (ms->s_state & MINIX_VALID_FS ||
- !(sb->u.minix_sb.s_mount_state & MINIX_VALID_FS))
+ !(sbi->s_mount_state & MINIX_VALID_FS))
return 0;
/* Mounting a rw partition read-only. */
- ms->s_state = sb->u.minix_sb.s_mount_state;
- mark_buffer_dirty(sb->u.minix_sb.s_sbh);
+ ms->s_state = sbi->s_mount_state;
+ mark_buffer_dirty(sbi->s_sbh);
sb->s_dirt = 1;
minix_commit_super(sb);
}
else {
/* Mount a partition which is read-only, read-write. */
- sb->u.minix_sb.s_mount_state = ms->s_state;
+ sbi->s_mount_state = ms->s_state;
ms->s_state &= ~MINIX_VALID_FS;
- mark_buffer_dirty(sb->u.minix_sb.s_sbh);
+ mark_buffer_dirty(sbi->s_sbh);
sb->s_dirt = 1;
- if (!(sb->u.minix_sb.s_mount_state & MINIX_VALID_FS))
+ if (!(sbi->s_mount_state & MINIX_VALID_FS))
printk ("MINIX-fs warning: remounting unchecked fs, "
"running fsck is recommended.\n");
- else if ((sb->u.minix_sb.s_mount_state & MINIX_ERROR_FS))
+ else if ((sbi->s_mount_state & MINIX_ERROR_FS))
printk ("MINIX-fs warning: remounting fs with errors, "
"running fsck is recommended.\n");
}
@@ -168,7 +170,7 @@
struct minix_super_block *ms;
int i, block;
struct inode *root_inode;
- struct minix_sb_info *sbi = &s->u.minix_sb;
+ struct minix_sb_info *sbi = minix_sb(s);
/* N.B. These should be compile-time tests.
Unfortunately that is impossible. */
@@ -316,14 +318,15 @@
static int minix_statfs(struct super_block *sb, struct statfs *buf)
{
+ struct minix_sb_info *sbi = minix_sb(sb);
buf->f_type = sb->s_magic;
buf->f_bsize = sb->s_blocksize;
- buf->f_blocks = (sb->u.minix_sb.s_nzones - sb->u.minix_sb.s_firstdatazone) << sb->u.minix_sb.s_log_zone_size;
+ buf->f_blocks = (sbi->s_nzones - sbi->s_firstdatazone) << sbi->s_log_zone_size;
buf->f_bfree = minix_count_free_blocks(sb);
buf->f_bavail = buf->f_bfree;
- buf->f_files = sb->u.minix_sb.s_ninodes;
+ buf->f_files = sbi->s_ninodes;
buf->f_ffree = minix_count_free_inodes(sb);
- buf->f_namelen = sb->u.minix_sb.s_namelen;
+ buf->f_namelen = sbi->s_namelen;
return 0;
}
diff -urN -X scripts/dontdiff linux-2.5.6/fs/minix/itree_v1.c linux/fs/minix/itree_v1.c
--- linux-2.5.6/fs/minix/itree_v1.c Wed Feb 6 11:47:05 2002
+++ linux/fs/minix/itree_v1.c Thu Mar 7 08:38:13 2002
@@ -28,7 +28,7 @@
if (block < 0) {
printk("minix_bmap: block<0");
- } else if (block >= (inode->i_sb->u.minix_sb.s_max_size/BLOCK_SIZE)) {
+ } else if (block >= (minix_sb(inode->i_sb)->s_max_size/BLOCK_SIZE)) {
printk("minix_bmap: block>big");
} else if (block < 7) {
offsets[n++] = block;
diff -urN -X scripts/dontdiff linux-2.5.6/fs/minix/itree_v2.c linux/fs/minix/itree_v2.c
--- linux-2.5.6/fs/minix/itree_v2.c Wed Feb 6 11:47:05 2002
+++ linux/fs/minix/itree_v2.c Thu Mar 7 08:38:13 2002
@@ -28,7 +28,7 @@
if (block < 0) {
printk("minix_bmap: block<0");
- } else if (block >= (inode->i_sb->u.minix_sb.s_max_size/BLOCK_SIZE)) {
+ } else if (block >= (minix_sb(inode->i_sb)->s_max_size/BLOCK_SIZE)) {
printk("minix_bmap: block>big");
} else if (block < 7) {
offsets[n++] = block;
diff -urN -X scripts/dontdiff linux-2.5.6/fs/minix/namei.c linux/fs/minix/namei.c
--- linux-2.5.6/fs/minix/namei.c Wed Feb 20 01:47:36 2002
+++ linux/fs/minix/namei.c Thu Mar 7 08:38:13 2002
@@ -38,7 +38,7 @@
int i;
const unsigned char *name;
- i = dentry->d_inode->i_sb->u.minix_sb.s_namelen;
+ i = minix_sb(dentry->d_inode->i_sb)->s_namelen;
if (i >= qstr->len)
return 0;
/* Truncate the name in place, avoids having to define a compare
@@ -63,7 +63,7 @@
dentry->d_op = dir->i_sb->s_root->d_op;
- if (dentry->d_name.len > dir->i_sb->u.minix_sb.s_namelen)
+ if (dentry->d_name.len > minix_sb(dir->i_sb)->s_namelen)
return ERR_PTR(-ENAMETOOLONG);
ino = minix_inode_by_name(dentry);
@@ -131,7 +131,7 @@
{
struct inode *inode = old_dentry->d_inode;
- if (inode->i_nlink >= inode->i_sb->u.minix_sb.s_link_max)
+ if (inode->i_nlink >= minix_sb(inode->i_sb)->s_link_max)
return -EMLINK;
inode->i_ctime = CURRENT_TIME;
@@ -145,7 +145,7 @@
struct inode * inode;
int err = -EMLINK;
- if (dir->i_nlink >= dir->i_sb->u.minix_sb.s_link_max)
+ if (dir->i_nlink >= minix_sb(dir->i_sb)->s_link_max)
goto out;
inc_count(dir);
@@ -221,7 +221,7 @@
static int minix_rename(struct inode * old_dir, struct dentry *old_dentry,
struct inode * new_dir, struct dentry *new_dentry)
{
- struct minix_sb_info * info = &old_dir->i_sb->u.minix_sb;
+ struct minix_sb_info * info = minix_sb(old_dir->i_sb);
struct inode * old_inode = old_dentry->d_inode;
struct inode * new_inode = new_dentry->d_inode;
struct page * dir_page = NULL;
diff -urN -X scripts/dontdiff linux-2.5.6/include/linux/minix_fs.h linux/include/linux/minix_fs.h
--- linux-2.5.6/include/linux/minix_fs.h Wed Feb 6 11:47:05 2002
+++ linux/include/linux/minix_fs.h Thu Mar 7 09:54:58 2002
@@ -32,7 +32,7 @@
#define MINIX_V1 0x0001 /* original minix fs */
#define MINIX_V2 0x0002 /* minix V2 fs */
-#define INODE_VERSION(inode) inode->i_sb->u.minix_sb.s_version
+#define INODE_VERSION(inode) minix_sb(inode->i_sb)->s_version
/*
* This is the original minix inode layout on disk.
@@ -90,6 +90,7 @@
#ifdef __KERNEL__
#include <linux/minix_fs_i.h>
+#include <linux/minix_fs_sb.h>
/*
* change the define below to 0 if you want names > info->s_namelen chars to be
@@ -131,6 +132,11 @@
extern struct file_operations minix_dir_operations;
extern struct dentry_operations minix_dentry_operations;
+static inline struct minix_sb_info *minix_sb(struct super_block *sb)
+{
+ return &sb->u.minix_sb;
+}
+
static inline struct minix_inode_info *minix_i(struct inode *inode)
{
return list_entry(inode, struct minix_inode_info, vfs_inode);
[-- Attachment #3: sb-minix-b1 --]
[-- Type: text/plain, Size: 1909 bytes --]
diff -urN linux/fs/minix/inode.c linux2/fs/minix/inode.c
--- linux/fs/minix/inode.c Thu Mar 7 09:39:46 2002
+++ linux2/fs/minix/inode.c Thu Mar 7 10:12:22 2002
@@ -70,6 +70,8 @@
brelse(sbi->s_zmap[i]);
brelse (sbi->s_sbh);
kfree(sbi->s_imap);
+ sb->u.generic_sbp = NULL;
+ kfree(sbi);
return;
}
@@ -170,7 +172,12 @@
struct minix_super_block *ms;
int i, block;
struct inode *root_inode;
- struct minix_sb_info *sbi = minix_sb(s);
+ struct minix_sb_info *sbi;
+
+ sbi = kmalloc(sizeof(struct minix_sb_info), GFP_KERNEL);
+ if (!sbi)
+ return -ENOMEM;
+ s->u.generic_sbp = sbi;
/* N.B. These should be compile-time tests.
Unfortunately that is impossible. */
@@ -313,6 +320,8 @@
out_bad_sb:
printk("MINIX-fs: unable to read superblock\n");
out:
+ s->u.generic_sbp = NULL;
+ kfree(sbi);
return -EINVAL;
}
diff -urN linux/include/linux/fs.h linux2/include/linux/fs.h
--- linux/include/linux/fs.h Thu Mar 7 09:55:00 2002
+++ linux2/include/linux/fs.h Thu Mar 7 10:11:08 2002
@@ -650,7 +650,6 @@
#define MNT_FORCE 0x00000001 /* Attempt to forcibily umount */
#define MNT_DETACH 0x00000002 /* Just detach from the tree */
-#include <linux/minix_fs_sb.h>
#include <linux/ext2_fs_sb.h>
#include <linux/ext3_fs_sb.h>
#include <linux/hpfs_fs_sb.h>
@@ -708,7 +707,6 @@
char s_id[32]; /* Informational name */
union {
- struct minix_sb_info minix_sb;
struct ext2_sb_info ext2_sb;
struct ext3_sb_info ext3_sb;
struct hpfs_sb_info hpfs_sb;
diff -urN linux/include/linux/minix_fs.h linux2/include/linux/minix_fs.h
--- linux/include/linux/minix_fs.h Thu Mar 7 09:54:58 2002
+++ linux2/include/linux/minix_fs.h Thu Mar 7 09:58:42 2002
@@ -134,7 +134,7 @@
static inline struct minix_sb_info *minix_sb(struct super_block *sb)
{
- return &sb->u.minix_sb;
+ return sb->u.generic_sbp;
}
static inline struct minix_inode_info *minix_i(struct inode *inode)
next reply other threads:[~2002-03-11 23:01 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2002-03-11 22:59 Brian Gerst [this message]
2002-03-12 13:32 ` [PATCH] struct superblock cleanup - minixfs Daniel Phillips
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