Steven N. Hirsch wrote:
> I applied your little patch to instrument the NFS subsystem. I'm able to
> reproduce the "semaphore in use" Aiee at will.
>
>
Oops, forgot the patch ...
Regards,
Bill
--------------792DC2201F09AFC1F2AF9E8C
Content-Type: text/plain; charset=us-ascii; name="nfsd_119-patch"
Content-Transfer-Encoding: 7bit
Content-Disposition: inline; filename="nfsd_119-patch"
--- linux-2.1.119/include/linux/nfsd/nfsfh.h.old Fri Aug 28 08:30:03 1998
+++ linux-2.1.119/include/linux/nfsd/nfsfh.h Sat Aug 29 14:11:20 1998
@@ -81,12 +81,12 @@
struct knfs_fh fh_handle; /* FH data */
struct dentry * fh_dentry; /* validated dentry */
struct svc_export * fh_export; /* export pointer */
+ int fh_dverified; /* dentry has been checked */
+ int fh_locked; /* inode locked by us */
size_t fh_pre_size; /* size before operation */
time_t fh_pre_mtime; /* mtime before oper */
time_t fh_pre_ctime; /* ctime before oper */
unsigned long fh_post_version;/* inode version after oper */
- unsigned char fh_locked; /* inode locked by us */
- unsigned char fh_dverified; /* dentry has been checked */
} svc_fh;
/*
@@ -133,22 +133,36 @@
static inline void
fh_lock(struct svc_fh *fhp)
{
- struct inode *inode = fhp->fh_dentry->d_inode;
+ struct dentry *dentry = fhp->fh_dentry;
+ struct inode *inode;
/*
dfprintk(FILEOP, "nfsd: fh_lock(%x/%ld) locked = %d\n",
SVCFH_DEV(fhp), SVCFH_INO(fhp), fhp->fh_locked);
*/
+ if (!fhp->fh_dverified) {
+ printk(KERN_ERR "fh_lock: fh not verified!\n");
+ return;
+ }
if (fhp->fh_locked) {
printk(KERN_WARNING "fh_lock: %s/%s already locked!\n",
- fhp->fh_dentry->d_parent->d_name.name,
- fhp->fh_dentry->d_name.name);
+ dentry->d_parent->d_name.name, dentry->d_name.name);
return;
}
+
+ inode = dentry->d_inode;
down(&inode->i_sem);
if (!fhp->fh_pre_mtime)
fhp->fh_pre_mtime = inode->i_mtime;
fhp->fh_locked = 1;
+
+ /* check for trouble ... */
+ if (!fhp->fh_dverified)
+ printk(KERN_ERR "fh_lock: not verified after down()!\n");
+ if (atomic_read(&inode->i_sem.count) > 0)
+ printk(KERN_ERR "fh_lock: %s/%s not really locked, count=%d\n",
+ dentry->d_parent->d_name.name, dentry->d_name.name,
+ atomic_read(&inode->i_sem.count));
}
/*
@@ -157,12 +171,21 @@
static inline void
fh_unlock(struct svc_fh *fhp)
{
+ if (!fhp->fh_dverified)
+ printk(KERN_ERR "fh_unlock: fh not verified!\n");
+
if (fhp->fh_locked) {
- struct inode *inode = fhp->fh_dentry->d_inode;
+ struct dentry *dentry = fhp->fh_dentry;
+ struct inode *inode = dentry->d_inode;
+
if (!fhp->fh_post_version)
fhp->fh_post_version = inode->i_version;
fhp->fh_locked = 0;
up(&inode->i_sem);
+ if (atomic_read(&inode->i_sem.count) > 1)
+ printk(KERN_ERR "fh_unlock: %s/%s has bad count %d\n",
+ dentry->d_parent->d_name.name, dentry->d_name.name,
+ atomic_read(&inode->i_sem.count));
}
}
--- linux-2.1.119/fs/nfsd/nfsfh.c.old Thu Aug 6 16:54:09 1998
+++ linux-2.1.119/fs/nfsd/nfsfh.c Sat Aug 29 12:05:57 1998
@@ -1107,7 +1107,7 @@
dprintk("nfsd: fh_compose(exp %x/%ld %s/%s, ino=%ld)\n",
exp->ex_dev, exp->ex_ino,
- dentry->d_parent->d_name.name, dentry->d_name.name,
+ parent->d_name.name, dentry->d_name.name,
(inode ? inode->i_ino : 0));
/*
@@ -1115,7 +1115,12 @@
* may not be done on error paths, but the cleanup must call fh_put.
* Fix this soon!
*/
+ if (fhp->fh_dverified) {
+ printk(KERN_ERR "fh_compose: fh %s/%s already verified??\n",
+ parent->d_name.name, dentry->d_name.name);
+ }
fh_init(fhp);
+
fhp->fh_handle.fh_dcookie = dentry;
if (inode) {
fhp->fh_handle.fh_ino = ino_t_to_u32(inode->i_ino);
--- linux-2.1.119/fs/nfsd/export.c.old Thu May 21 13:57:47 1998
+++ linux-2.1.119/fs/nfsd/export.c Sat Aug 29 12:01:04 1998
@@ -392,14 +392,15 @@
int
exp_rootfh(struct svc_client *clp, kdev_t dev, ino_t ino, struct knfs_fh *f)
{
- struct svc_export *exp = NULL;
- struct svc_fh fh;
+ struct svc_export *exp;
struct dentry *dentry;
struct inode *inode;
+ struct svc_fh fh;
dprintk("nfsd: exp_rootfh(%s:%x/%ld)\n", clp->cl_ident, dev, ino);
- if (!(exp = exp_get(clp, dev, ino)))
+ exp = exp_get(clp, dev, ino);
+ if (!exp)
return -EPERM;
dentry = exp->ex_dentry;
@@ -414,8 +415,11 @@
dev, ino, inode->i_dev, inode->i_ino);
}
- dget(dentry);
- fh_compose(&fh, exp, dentry);
+ /*
+ * fh must be initialized before calling fh_compose
+ */
+ fh_init(&fh);
+ fh_compose(&fh, exp, dget(dentry));
memcpy(f, &fh.fh_handle, sizeof(struct knfs_fh));
fh_put(&fh);
--------------792DC2201F09AFC1F2AF9E8C--
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.altern.org/andrebalsa/doc/lkml-faq.html