[PATCH 006 of 9] knfsd: Remove nfsd_versbits as intermediate storage for desired versions.

NeilBrown
2006-07-25T01:55:40Z

We have an array 'nfsd_version' which lists the available versions
of nfsd, and 'nfsd_versions' (poor choice there :-() which lists
the currently active versions.

Then we have a bitmap - nfsd_versbits which says which versions are
wanted. The bits in this bitset cause content to be copied from
nfsd_version to nfsd_versions when nfsd starts.

This patch removes nfsd_versbits and moves information directly from
nfsd_version to nfsd_versions when requests for version changes arrive.

Note that this doesn't make it possible to change versions while the
server is running. This is because serv->sv_xdrsize is calculated when
a service is created, and used when threads are created, and xdrsize
depends on the active versions.

Signed-off-by: Neil Brown <neilb@suse.de>

### Diffstat output
./fs/nfsd/nfsctl.c | 18 +++----
./fs/nfsd/nfssvc.c | 93 ++++++++++++++++++++++-------------------
./include/linux/nfsd/nfsd.h | 4 +
./include/linux/nfsd/syscall.h | 17 -------
4 files changed, 62 insertions(+), 70 deletions(-)

diff .prev/fs/nfsd/nfsctl.c ./fs/nfsd/nfsctl.c
--- .prev/fs/nfsd/nfsctl.c 2006-07-24 15:17:36.000000000 +1000
+++ ./fs/nfsd/nfsctl.c 2006-07-24 15:17:36.000000000 +1000
@@ -35,8 +35,6 @@

#include <asm/uaccess.h>

-unsigned int nfsd_versbits = ~0;
-
/*
* We have a single directory with 9 nodes in it.
*/
@@ -372,6 +370,10 @@ static ssize_t write_versions(struct fil

if (size>0) {
if (nfsd_serv)
+ /* Cannot change versions without updating
+ * nfsd_serv->sv_xdrsize, and reallocing
+ * rq_argp and rq_resp
+ */
return -EBUSY;
if (buf[size-1] != '\n')
return -EINVAL;
@@ -390,10 +392,7 @@ static ssize_t write_versions(struct fil
case 2:
case 3:
case 4:
- if (sign != '-')
- NFSCTL_VERSET(nfsd_versbits, num);
- else
- NFSCTL_VERUNSET(nfsd_versbits, num);
+ nfsd_vers(num, sign == '-' ? NFSD_CLEAR : NFSD_SET);
break;
default:
return -EINVAL;
@@ -404,16 +403,15 @@ static ssize_t write_versions(struct fil
/* If all get turned off, turn them back on, as
* having no versions is BAD
*/
- if ((nfsd_versbits & NFSCTL_VERALL)==0)
- nfsd_versbits = NFSCTL_VERALL;
+ nfsd_reset_versions();
}
/* Now write current state into reply buffer */
len = 0;
sep = "";
for (num=2 ; num <= 4 ; num++)
- if (NFSCTL_VERISSET(NFSCTL_VERALL, num)) {
+ if (nfsd_vers(num, NFSD_AVAIL)) {
len += sprintf(buf+len, "%s%c%d", sep,
- NFSCTL_VERISSET(nfsd_versbits, num)?'+':'-',
+ nfsd_vers(num, NFSD_TEST)?'+':'-',
num);
sep = " ";
}

diff .prev/fs/nfsd/nfssvc.c ./fs/nfsd/nfssvc.c
--- .prev/fs/nfsd/nfssvc.c 2006-07-24 15:15:04.000000000 +1000
+++ ./fs/nfsd/nfssvc.c 2006-07-24 15:17:36.000000000 +1000
@@ -117,6 +117,32 @@ struct svc_program nfsd_program = {

};

+int nfsd_vers(int vers, enum vers_op change)
+{
+ if (vers < NFSD_MINVERS || vers >= NFSD_NRVERS)
+ return -1;
+ switch(change) {
+ case NFSD_SET:
+ nfsd_versions[vers] = nfsd_version[vers];
+ break;
+#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
+ if (vers < NFSD_ACL_NRVERS)
+ nfsd_acl_version[vers] = nfsd_acl_version[vers];
+#endif
+ case NFSD_CLEAR:
+ nfsd_versions[vers] = NULL;
+#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
+ if (vers < NFSD_ACL_NRVERS)
+ nfsd_acl_version[vers] = NULL;
+#endif
+ break;
+ case NFSD_TEST:
+ return nfsd_versions[vers] != NULL;
+ case NFSD_AVAIL:
+ return nfsd_version[vers] != NULL;
+ }
+ return 0;
+}
/*
* Maximum number of nfsd processes
*/
@@ -147,16 +173,36 @@ static void nfsd_last_thread(struct svc_
nfsd_export_flush();
}
}
+
+void nfsd_reset_versions(void)
+{
+ int found_one = 0;
+ int i;
+
+ for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++) {
+ if (nfsd_program.pg_vers[i])
+ found_one = 1;
+ }
+
+ if (!found_one) {
+ for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++)
+ nfsd_program.pg_vers[i] = nfsd_version[i];
+#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
+ for (i = NFSD_ACL_MINVERS; i < NFSD_ACL_NRVERS; i++)
+ nfsd_acl_program.pg_vers[i] =
+ nfsd_acl_version[i];
+#endif
+ }
+}
+
int
nfsd_svc(unsigned short port, int nrservs)
{
int error;
- int found_one, i;
struct list_head *victim;

lock_kernel();
- dprintk("nfsd: creating service: vers 0x%x\n",
- nfsd_versbits);
+ dprintk("nfsd: creating service\n");
error = -EINVAL;
if (nrservs <= 0)
nrservs = 0;
@@ -171,46 +217,7 @@ nfsd_svc(unsigned short port, int nrserv
if (error<0)
goto out;
if (!nfsd_serv) {
- /*
- * Use the nfsd_ctlbits to define which
- * versions that will be advertised.
- * If nfsd_ctlbits doesn't list any version,
- * export them all.
- */
- found_one = 0;
-
- for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++) {
- if (NFSCTL_VERISSET(nfsd_versbits, i)) {
- nfsd_program.pg_vers[i] = nfsd_version[i];
- found_one = 1;
- } else
- nfsd_program.pg_vers[i] = NULL;
- }
-
- if (!found_one) {
- for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++)
- nfsd_program.pg_vers[i] = nfsd_version[i];
- }
-
-
-#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
- found_one = 0;
-
- for (i = NFSD_ACL_MINVERS; i < NFSD_ACL_NRVERS; i++) {
- if (NFSCTL_VERISSET(nfsd_versbits, i)) {
- nfsd_acl_program.pg_vers[i] =
- nfsd_acl_version[i];
- found_one = 1;
- } else
- nfsd_acl_program.pg_vers[i] = NULL;
- }
-
- if (!found_one) {
- for (i = NFSD_ACL_MINVERS; i < NFSD_ACL_NRVERS; i++)
- nfsd_acl_program.pg_vers[i] =
- nfsd_acl_version[i];
- }
-#endif
+ nfsd_reset_versions();

atomic_set(&nfsd_busy, 0);
error = -ENOMEM;

diff .prev/include/linux/nfsd/nfsd.h ./include/linux/nfsd/nfsd.h
--- .prev/include/linux/nfsd/nfsd.h 2006-07-24 15:17:36.000000000 +1000
+++ ./include/linux/nfsd/nfsd.h 2006-07-24 15:17:36.000000000 +1000
@@ -140,6 +140,10 @@ struct posix_acl *nfsd_get_posix_acl(str
int nfsd_set_posix_acl(struct svc_fh *, int, struct posix_acl *);
#endif

+enum vers_op {NFSD_SET, NFSD_CLEAR, NFSD_TEST, NFSD_AVAIL };
+int nfsd_vers(int vers, enum vers_op change);
+void nfsd_reset_versions(void);
+

/*
* NFSv4 State

diff .prev/include/linux/nfsd/syscall.h ./include/linux/nfsd/syscall.h
--- .prev/include/linux/nfsd/syscall.h 2006-07-24 15:17:36.000000000 +1000
+++ ./include/linux/nfsd/syscall.h 2006-07-24 15:17:36.000000000 +1000
@@ -38,21 +38,6 @@
#define NFSCTL_GETFD 7 /* get an fh by path (used by mountd) */
#define NFSCTL_GETFS 8 /* get an fh by path with max FH len */

-/*
- * Macros used to set version
- */
-#define NFSCTL_VERSET(_cltbits, _v) ((_cltbits) |= (1 << (_v)))
-#define NFSCTL_VERUNSET(_cltbits, _v) ((_cltbits) &= ~(1 << (_v)))
-#define NFSCTL_VERISSET(_cltbits, _v) ((_cltbits) & (1 << (_v)))
-
-#if defined(CONFIG_NFSD_V4)
-#define NFSCTL_VERALL (0x1c /* 0b011100 */)
-#elif defined(CONFIG_NFSD_V3)
-#define NFSCTL_VERALL (0x0c /* 0b001100 */)
-#else
-#define NFSCTL_VERALL (0x04 /* 0b000100 */)
-#endif
-
/* SVC */
struct nfsctl_svc {
unsigned short svc_port;
@@ -134,8 +119,6 @@ extern int exp_delclient(struct nfsctl_
extern int exp_export(struct nfsctl_export *nxp);
extern int exp_unexport(struct nfsctl_export *nxp);

-extern unsigned int nfsd_versbits;
-
#endif /* __KERNEL__ */

#endif /* NFSD_SYSCALL_H */