This serves to decrease the size of struct inode a bit,
and makes sure that a later increase of sizeof(dev_t)
does not make struct inode bigger than it used to be.
The i_dev field is deleted and the few uses are replaced
by i_sb->s_dev.
There is a single side effect: a stat on a socket now sees
a nonzero st_dev. There is nothing against that - FreeBSD
has a nonzero value as well - but there is at least one
utility (fuser) that will need an update.
Andries
Patch against (vanilla) 2.5.48.
diff -u --recursive --new-file -X /linux/dontdiff a/fs/coda/coda_linux.c b/fs/coda/coda_linux.c
--- a/fs/coda/coda_linux.c Mon Nov 18 10:57:19 2002
+++ b/fs/coda/coda_linux.c Fri Nov 22 00:21:21 2002
@@ -100,7 +100,7 @@
void coda_vattr_to_iattr(struct inode *inode, struct coda_vattr *attr)
{
int inode_type;
- /* inode's i_dev, i_flags, i_ino are set by iget
+ /* inode's i_flags, i_ino are set by iget
XXX: is this all we need ??
*/
switch (attr->va_type) {
diff -u --recursive --new-file -X /linux/dontdiff a/fs/inode.c b/fs/inode.c
--- a/fs/inode.c Mon Nov 18 10:57:20 2002
+++ b/fs/inode.c Fri Nov 22 00:21:21 2002
@@ -102,7 +102,6 @@
struct address_space * const mapping = &inode->i_data;
inode->i_sb = sb;
- inode->i_dev = sb->s_dev;
inode->i_blkbits = sb->s_blocksize_bits;
inode->i_flags = 0;
atomic_set(&inode->i_count, 1);
diff -u --recursive --new-file -X /linux/dontdiff a/fs/intermezzo/presto.c b/fs/intermezzo/presto.c
--- a/fs/intermezzo/presto.c Thu Oct 17 02:28:40 2002
+++ b/fs/intermezzo/presto.c Fri Nov 22 00:21:21 2002
@@ -67,7 +67,7 @@
CDEBUG(D_PSDEV, "\n");
if ( !cache ) {
CERROR("PRESTO: BAD: cannot find cache for dev %d, ino %ld\n",
- inode->i_dev, inode->i_ino);
+ inode->i_sb->s_dev, inode->i_ino);
EXIT;
return -1;
}
diff -u --recursive --new-file -X /linux/dontdiff a/fs/intermezzo/vfs.c b/fs/intermezzo/vfs.c
--- a/fs/intermezzo/vfs.c Mon Nov 18 10:57:20 2002
+++ b/fs/intermezzo/vfs.c Fri Nov 22 00:21:21 2002
@@ -182,7 +182,7 @@
{
int minor = presto_f2m(fset);
int errorval = izo_channels[minor].uc_errorval;
- kdev_t dev = to_kdev_t(fset->fset_dentry->d_inode->i_dev);
+ kdev_t dev = to_kdev_t(fset->fset_dentry->d_inode->i_sb->s_dev);
if (errorval && errorval == (long)value && !is_read_only(dev)) {
CDEBUG(D_SUPER, "setting device %s read only\n", kdevname(dev));
@@ -763,7 +763,7 @@
goto exit_lock;
error = -EXDEV;
- if (dir->d_inode->i_dev != inode->i_dev)
+ if (dir->d_inode->i_sb->s_dev != inode->i_sb->s_dev)
goto exit_lock;
/*
@@ -1820,7 +1820,7 @@
if (error)
return error;
- if (new_dir->i_dev != old_dir->i_dev)
+ if (new_dir->i_sb->s_dev != old_dir->i_sb->s_dev)
return -EXDEV;
if (!new_dentry->d_inode)
@@ -1901,7 +1901,7 @@
if (error)
return error;
- if (new_dir->i_dev != old_dir->i_dev)
+ if (new_dir->i_sb->s_dev != old_dir->i_sb->s_dev)
return -EXDEV;
if (!new_dentry->d_inode)
diff -u --recursive --new-file -X /linux/dontdiff a/fs/locks.c b/fs/locks.c
--- a/fs/locks.c Mon Nov 18 10:57:20 2002
+++ b/fs/locks.c Fri Nov 22 00:21:21 2002
@@ -1766,7 +1766,7 @@
#else
/* kdevname is a broken interface. but we expose it to userspace */
out += sprintf(out, "%d %s:%ld ", fl->fl_pid,
- inode ? kdevname(to_kdev_t(inode->i_dev)) : "<none>",
+ inode ? kdevname(to_kdev_t(inode->i_sb->s_dev)) : "<none>",
inode ? inode->i_ino : 0);
#endif
if (IS_POSIX(fl)) {
diff -u --recursive --new-file -X /linux/dontdiff a/fs/nfsd/nfs3xdr.c b/fs/nfsd/nfs3xdr.c
--- a/fs/nfsd/nfs3xdr.c Mon Nov 18 10:57:20 2002
+++ b/fs/nfsd/nfs3xdr.c Fri Nov 22 00:21:21 2002
@@ -226,7 +226,7 @@
&& (fhp->fh_export->ex_flags & NFSEXP_FSID))
p = xdr_encode_hyper(p, (u64) fhp->fh_export->ex_fsid);
else
- p = xdr_encode_hyper(p, (u64) inode->i_dev);
+ p = xdr_encode_hyper(p, (u64) inode->i_sb->s_dev);
p = xdr_encode_hyper(p, (u64) inode->i_ino);
time.tv_sec = fhp->fh_post_atime;
time.tv_nsec = 0;
diff -u --recursive --new-file -X /linux/dontdiff a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
--- a/fs/nfsd/vfs.c Mon Nov 18 10:57:20 2002
+++ b/fs/nfsd/vfs.c Fri Nov 22 00:21:21 2002
@@ -632,7 +632,7 @@
#endif
/* Get readahead parameters */
- ra = nfsd_get_raparms(inode->i_dev, inode->i_ino);
+ ra = nfsd_get_raparms(inode->i_sb->s_dev, inode->i_ino);
if (ra)
file.f_ra = ra->p_ra;
@@ -752,7 +752,7 @@
*/
if (EX_WGATHER(exp)) {
if (atomic_read(&inode->i_writecount) > 1
- || (last_ino == inode->i_ino && last_dev == inode->i_dev)) {
+ || (last_ino == inode->i_ino && last_dev == inode->i_sb->s_dev)) {
dprintk("nfsd: write defer %d\n", current->pid);
set_current_state(TASK_UNINTERRUPTIBLE);
schedule_timeout((HZ+99)/100);
@@ -769,7 +769,7 @@
#endif
}
last_ino = inode->i_ino;
- last_dev = inode->i_dev;
+ last_dev = inode->i_sb->s_dev;
}
dprintk("nfsd: write complete err=%d\n", err);
diff -u --recursive --new-file -X /linux/dontdiff a/fs/proc/array.c b/fs/proc/array.c
--- a/fs/proc/array.c Tue Nov 5 09:18:10 2002
+++ b/fs/proc/array.c Fri Nov 22 00:21:21 2002
@@ -484,8 +484,9 @@
dev = 0;
ino = 0;
if (map->vm_file != NULL) {
- dev = map->vm_file->f_dentry->d_inode->i_dev;
- ino = map->vm_file->f_dentry->d_inode->i_ino;
+ struct inode *inode = map->vm_file->f_dentry->d_inode;
+ dev = inode->i_sb->s_dev;
+ ino = inode->i_ino;
line = d_path(map->vm_file->f_dentry,
map->vm_file->f_vfsmnt,
buf, PAGE_SIZE);
diff -u --recursive --new-file -X /linux/dontdiff a/fs/stat.c b/fs/stat.c
--- a/fs/stat.c Mon Nov 18 10:57:22 2002
+++ b/fs/stat.c Fri Nov 22 00:21:21 2002
@@ -18,7 +18,7 @@
void generic_fillattr(struct inode *inode, struct kstat *stat)
{
- stat->dev = inode->i_dev;
+ stat->dev = inode->i_sb->s_dev;
stat->ino = inode->i_ino;
stat->mode = inode->i_mode;
stat->nlink = inode->i_nlink;
diff -u --recursive --new-file -X /linux/dontdiff a/fs/udf/inode.c b/fs/udf/inode.c
--- a/fs/udf/inode.c Mon Nov 18 10:57:22 2002
+++ b/fs/udf/inode.c Fri Nov 22 00:21:21 2002
@@ -920,7 +920,6 @@
* Set defaults, but the inode is still incomplete!
* Note: get_new_inode() sets the following on a new inode:
* i_sb = sb
- * i_dev = sb->s_dev;
* i_no = ino
* i_flags = sb->s_flags
* i_state = 0
diff -u --recursive --new-file -X /linux/dontdiff a/fs/xfs/xfs_iget.c b/fs/xfs/xfs_iget.c
--- a/fs/xfs/xfs_iget.c Thu Nov 14 17:10:30 2002
+++ b/fs/xfs/xfs_iget.c Fri Nov 22 00:21:21 2002
@@ -247,8 +247,8 @@
/*
* Read the disk inode attributes into a new inode structure and get
* a new vnode for it. Initialize the inode lock so we can idestroy
- * it soon if it's a dup. This should also initialize i_dev, i_ino,
- * i_bno, i_mount, and i_index.
+ * it soon if it's a dup. This should also initialize i_ino, i_bno,
+ * i_mount, and i_index.
*/
error = xfs_iread(mp, tp, ino, &ip, bno);
if (error) {
diff -u --recursive --new-file -X /linux/dontdiff a/fs/xfs/xfsidbg.c b/fs/xfs/xfsidbg.c
--- a/fs/xfs/xfsidbg.c Thu Nov 14 17:10:30 2002
+++ b/fs/xfs/xfsidbg.c Fri Nov 22 00:21:21 2002
@@ -1639,7 +1639,7 @@
kdb_printf(" i_ino = %lu i_count = %u i_dev = 0x%x i_size %Ld\n",
ip->i_ino, atomic_read(&ip->i_count),
- ip->i_dev, ip->i_size);
+ ip->i_sb->s_dev, ip->i_size);
kdb_printf(
" i_mode = 0x%x i_nlink = %d i_rdev = 0x%x i_state = 0x%lx\n",
diff -u --recursive --new-file -X /linux/dontdiff a/include/linux/fs.h b/include/linux/fs.h
--- a/include/linux/fs.h Mon Nov 18 10:57:23 2002
+++ b/include/linux/fs.h Fri Nov 22 00:21:21 2002
@@ -362,7 +362,6 @@
struct list_head i_dentry;
unsigned long i_ino;
atomic_t i_count;
- dev_t i_dev;
umode_t i_mode;
unsigned int i_nlink;
uid_t i_uid;
diff -u --recursive --new-file -X /linux/dontdiff a/net/socket.c b/net/socket.c
--- a/net/socket.c Mon Nov 18 10:57:24 2002
+++ b/net/socket.c Fri Nov 22 00:21:46 2002
@@ -468,7 +468,6 @@
if (!inode)
return NULL;
- inode->i_dev = 0;
sock = SOCKET_I(inode);
inode->i_mode = S_IFSOCK|S_IRWXUGO;
On Fri, 22 Nov 2002 [email protected] wrote:
>
> The i_dev field is deleted and the few uses are replaced
> by i_sb->s_dev.
Applied.
> There is a single side effect: a stat on a socket now sees
> a nonzero st_dev. There is nothing against that - FreeBSD
> has a nonzero value as well - but there is at least one
> utility (fuser) that will need an update.
Looking at the patch (not testing it), as far as I can tell we'll return a
basically random number that is just whatever the anonymous super-block
was allocated, right?
I'm not convinced that returning random numbers to user space is
necessarily a great idea.. That said, I think we already do it for unnamed
pipes anyway, so I'm more wondering if we should have some way to map
these numbews (in user space) to a valid thing, so that they wouldn't just
be random numbers.
(In other words: I like the patch, and I'm not really complaining about
this new behavour at all. It's just the "randomness" as far as user space
goes that bothers me a bit, since it seems to imply bad interface design).
Linus
Followup to: <[email protected]>
By author: Linus Torvalds <[email protected]>
In newsgroup: linux.dev.kernel
>
> Applied.
>
> > There is a single side effect: a stat on a socket now sees
> > a nonzero st_dev. There is nothing against that - FreeBSD
> > has a nonzero value as well - but there is at least one
> > utility (fuser) that will need an update.
>
> Looking at the patch (not testing it), as far as I can tell we'll return a
> basically random number that is just whatever the anonymous super-block
> was allocated, right?
>
> I'm not convinced that returning random numbers to user space is
> necessarily a great idea.. That said, I think we already do it for unnamed
> pipes anyway, so I'm more wondering if we should have some way to map
> these numbews (in user space) to a valid thing, so that they wouldn't just
> be random numbers.
>
What's really important is that they don't map to anything else. I
don't think it matters what the numbers is, since there is a much
better way to find out that you're a pipe or a socket.
-hpa
--
<[email protected]> at work, <[email protected]> in private!
"Unix gives you enough rope to shoot yourself in the foot."
http://www.zytor.com/~hpa/puzzle.txt <[email protected]>
> I'm not convinced that returning random numbers to user space is
> necessarily a great idea.. That said, I think we already do it for unnamed
> pipes anyway, so I'm more wondering if we should have some way to map
> these numbews (in user space) to a valid thing, so that they wouldn't just
> be random numbers.
That just means someone has to implement a trivial ->getattr wrapper for
sockfs that zeroes out the st_dev field.
From [email protected] Fri Nov 22 00:57:03 2002
> There is a single side effect: a stat on a socket now sees
> a nonzero st_dev. There is nothing against that - FreeBSD
> has a nonzero value as well - but there is at least one
> utility (fuser) that will need an update.
Looking at the patch (not testing it), as far as I can tell we'll return a
basically random number that is just whatever the anonymous super-block
was allocated, right?
Right.
I'm not convinced that returning random numbers to user space is
necessarily a great idea.. That said, I think we already do it for unnamed
pipes anyway, so I'm more wondering if we should have some way to map
these numbers (in user space) to a valid thing, so that they wouldn't just
be random numbers.
I don't know. We can try in-kernel to give these well-known services
well-known numbers. Or we can give them essentially random
numbers like today but publish these somewhere, e.g. under /sys.
Both are easy, but seem too heavy for a value used by nobody.
We have process IDs and anonymous fs IDs, and both are just what
they happen to be.
Andries
[If userspace wants to know the present value, then create a socket,
stat, 3! Create a pipe, stat, 7!]