[PATCH 24/30] IGET: Stop ROMFS from using iget() and read_inode()

From: David Howells
Date: Mon Oct 01 2007 - 09:18:43 EST


Stop the ROMFS filesystem from using iget() and read_inode(). Replace
romfs_read_inode() with romfs_iget(), and call that instead of iget().
romfs_iget() then uses iget_locked() directly and returns a proper error code
instead of an inode in the event of an error.

romfs_fill_super() returns any error incurred when getting the root inode
instead of EINVAL.

Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
---

fs/romfs/inode.c | 45 +++++++++++++++++++++++++++++++--------------
1 files changed, 31 insertions(+), 14 deletions(-)

diff --git a/fs/romfs/inode.c b/fs/romfs/inode.c
index dae7945..5071c9a 100644
--- a/fs/romfs/inode.c
+++ b/fs/romfs/inode.c
@@ -84,6 +84,8 @@ struct romfs_inode_info {
struct inode vfs_inode;
};

+static struct inode *romfs_iget(struct super_block *, unsigned long);
+
/* instead of private superblock data */
static inline unsigned long romfs_maxsize(struct super_block *sb)
{
@@ -117,7 +119,7 @@ static int romfs_fill_super(struct super_block *s, void *data, int silent)
struct buffer_head *bh;
struct romfs_super_block *rsb;
struct inode *root;
- int sz;
+ int sz, ret = -EINVAL;

/* I would parse the options here, but there are none.. :) */

@@ -157,10 +159,13 @@ static int romfs_fill_super(struct super_block *s, void *data, int silent)
& ROMFH_MASK;

s->s_op = &romfs_ops;
- root = iget(s, sz);
- if (!root)
+ root = romfs_iget(s, sz);
+ if (IS_ERR(root)) {
+ ret = PTR_ERR(root);
goto out;
+ }

+ ret = -ENOMEM;
s->s_root = d_alloc_root(root);
if (!s->s_root)
goto outiput;
@@ -173,7 +178,7 @@ outiput:
out:
brelse(bh);
outnobh:
- return -EINVAL;
+ return ret;
}

/* That's simple too. */
@@ -389,8 +394,11 @@ romfs_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
if ((be32_to_cpu(ri.next) & ROMFH_TYPE) == ROMFH_HRD)
offset = be32_to_cpu(ri.spec) & ROMFH_MASK;

- if ((inode = iget(dir->i_sb, offset)))
- goto outi;
+ inode = romfs_iget(dir->i_sb, offset);
+ if (IS_ERR(inode)) {
+ res = PTR_ERR(inode);
+ goto out;
+ }

/*
* it's a bit funky, _lookup needs to return an error code
@@ -402,7 +410,7 @@ romfs_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
*/

out0: inode = NULL;
-outi: res = 0;
+ res = 0;
d_add (dentry, inode);

out: unlock_kernel();
@@ -478,20 +486,28 @@ static mode_t romfs_modemap[] =
S_IFBLK+0600, S_IFCHR+0600, S_IFSOCK+0644, S_IFIFO+0644
};

-static void
-romfs_read_inode(struct inode *i)
+static struct inode *
+romfs_iget(struct super_block *sb, unsigned long ino)
{
- int nextfh, ino;
+ int nextfh;
struct romfs_inode ri;
+ struct inode *i;
+
+ ino &= ROMFH_MASK;
+ i = iget_locked(sb, ino);
+ if (!i)
+ return ERR_PTR(-ENOMEM);
+ if (!(i->i_state & I_NEW))
+ return i;

- ino = i->i_ino & ROMFH_MASK;
i->i_mode = 0;

/* Loop for finding the real hard link */
for(;;) {
if (romfs_copyfrom(i, &ri, ino, ROMFH_SIZE) <= 0) {
- printk("romfs: read error for inode 0x%x\n", ino);
- return;
+ printk("romfs: read error for inode 0x%lx\n", ino);
+ iget_failed(i);
+ return ERR_PTR(-EIO);
}
/* XXX: do romfs_checksum here too (with name) */

@@ -548,6 +564,8 @@ romfs_read_inode(struct inode *i)
init_special_inode(i, ino,
MKDEV(nextfh>>16,nextfh&0xffff));
}
+ unlock_new_inode(i);
+ return i;
}

static struct kmem_cache * romfs_inode_cachep;
@@ -599,7 +617,6 @@ static int romfs_remount(struct super_block *sb, int *flags, char *data)
static const struct super_operations romfs_ops = {
.alloc_inode = romfs_alloc_inode,
.destroy_inode = romfs_destroy_inode,
- .read_inode = romfs_read_inode,
.statfs = romfs_statfs,
.remount_fs = romfs_remount,
};

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/