[PATCH] knfsd: Allow run-time selection of NFS versions to export
Provide a file in the NFSD filesystem that allows setting and querying of
which version of NFS are being exported. Changes are only allowed while no
server is running.
Signed-off-by: Steve Dickson <steved@redhat.com>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c
index 2a99a0b..a0871b3 100644
--- a/fs/nfsd/nfsctl.c
+++ b/fs/nfsd/nfsctl.c
@@ -23,6 +23,7 @@
#include <linux/seq_file.h>
#include <linux/pagemap.h>
#include <linux/init.h>
+#include <linux/string.h>
#include <linux/nfs.h>
#include <linux/nfsd_idmap.h>
@@ -35,6 +36,8 @@
#include <asm/uaccess.h>
+unsigned int nfsd_versbits = ~0;
+
/*
* We have a single directory with 9 nodes in it.
*/
@@ -50,8 +53,15 @@
NFSD_List,
NFSD_Fh,
NFSD_Threads,
+ NFSD_Versions,
+ /*
+ * The below MUST come last. Otherwise we leave a hole in nfsd_files[]
+ * with !CONFIG_NFSD_V4 and simple_fill_super() goes oops
+ */
+#ifdef CONFIG_NFSD_V4
NFSD_Leasetime,
NFSD_RecoveryDir,
+#endif
};
/*
@@ -66,8 +76,11 @@
static ssize_t write_getfs(struct file *file, char *buf, size_t size);
static ssize_t write_filehandle(struct file *file, char *buf, size_t size);
static ssize_t write_threads(struct file *file, char *buf, size_t size);
+static ssize_t write_versions(struct file *file, char *buf, size_t size);
+#ifdef CONFIG_NFSD_V4
static ssize_t write_leasetime(struct file *file, char *buf, size_t size);
static ssize_t write_recoverydir(struct file *file, char *buf, size_t size);
+#endif
static ssize_t (*write_op[])(struct file *, char *, size_t) = {
[NFSD_Svc] = write_svc,
@@ -79,8 +92,11 @@
[NFSD_Getfs] = write_getfs,
[NFSD_Fh] = write_filehandle,
[NFSD_Threads] = write_threads,
+ [NFSD_Versions] = write_versions,
+#ifdef CONFIG_NFSD_V4
[NFSD_Leasetime] = write_leasetime,
[NFSD_RecoveryDir] = write_recoverydir,
+#endif
};
static ssize_t nfsctl_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
@@ -343,6 +359,70 @@
return strlen(buf);
}
+static ssize_t write_versions(struct file *file, char *buf, size_t size)
+{
+ /*
+ * Format:
+ * [-/+]vers [-/+]vers ...
+ */
+ char *mesg = buf;
+ char *vers, sign;
+ int len, num;
+ ssize_t tlen = 0;
+ char *sep;
+
+ if (size>0) {
+ if (nfsd_serv)
+ return -EBUSY;
+ if (buf[size-1] != '\n')
+ return -EINVAL;
+ buf[size-1] = 0;
+
+ vers = mesg;
+ len = qword_get(&mesg, vers, size);
+ if (len <= 0) return -EINVAL;
+ do {
+ sign = *vers;
+ if (sign == '+' || sign == '-')
+ num = simple_strtol((vers+1), NULL, 0);
+ else
+ num = simple_strtol(vers, NULL, 0);
+ switch(num) {
+ case 2:
+ case 3:
+ case 4:
+ if (sign != '-')
+ NFSCTL_VERSET(nfsd_versbits, num);
+ else
+ NFSCTL_VERUNSET(nfsd_versbits, num);
+ break;
+ default:
+ return -EINVAL;
+ }
+ vers += len + 1;
+ tlen += len;
+ } while ((len = qword_get(&mesg, vers, size)) > 0);
+ /* 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;
+ }
+ /* Now write current state into reply buffer */
+ len = 0;
+ sep = "";
+ for (num=2 ; num <= 4 ; num++)
+ if (NFSCTL_VERISSET(NFSCTL_VERALL, num)) {
+ len += sprintf(buf+len, "%s%c%d", sep,
+ NFSCTL_VERISSET(nfsd_versbits, num)?'+':'-',
+ num);
+ sep = " ";
+ }
+ len += sprintf(buf+len, "\n");
+ return len;
+}
+
+#ifdef CONFIG_NFSD_V4
extern time_t nfs4_leasetime(void);
static ssize_t write_leasetime(struct file *file, char *buf, size_t size)
@@ -384,6 +464,7 @@
status = nfs4_reset_recoverydir(recdir);
return strlen(buf);
}
+#endif
/*----------------------------------------------------------------------------*/
/*
@@ -403,6 +484,7 @@
[NFSD_List] = {"exports", &exports_operations, S_IRUGO},
[NFSD_Fh] = {"filehandle", &transaction_ops, S_IWUSR|S_IRUSR},
[NFSD_Threads] = {"threads", &transaction_ops, S_IWUSR|S_IRUSR},
+ [NFSD_Versions] = {"versions", &transaction_ops, S_IWUSR|S_IRUSR},
#ifdef CONFIG_NFSD_V4
[NFSD_Leasetime] = {"nfsv4leasetime", &transaction_ops, S_IWUSR|S_IRUSR},
[NFSD_RecoveryDir] = {"nfsv4recoverydir", &transaction_ops, S_IWUSR|S_IRUSR},
diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c
index 1697539..0568ff8 100644
--- a/fs/nfsd/nfssvc.c
+++ b/fs/nfsd/nfssvc.c
@@ -30,6 +30,7 @@
#include <linux/nfsd/nfsd.h>
#include <linux/nfsd/stats.h>
#include <linux/nfsd/cache.h>
+#include <linux/nfsd/syscall.h>
#include <linux/lockd/bind.h>
#include <linux/nfsacl.h>
@@ -52,7 +53,7 @@
extern struct svc_program nfsd_program;
static void nfsd(struct svc_rqst *rqstp);
struct timeval nfssvc_boot;
-static struct svc_serv *nfsd_serv;
+ struct svc_serv *nfsd_serv;
static atomic_t nfsd_busy;
static unsigned long nfsd_last_call;
static DEFINE_SPINLOCK(nfsd_call_lock);
@@ -63,6 +64,31 @@
};
static struct list_head nfsd_list = LIST_HEAD_INIT(nfsd_list);
+static struct svc_version * nfsd_version[] = {
+ [2] = &nfsd_version2,
+#if defined(CONFIG_NFSD_V3)
+ [3] = &nfsd_version3,
+#endif
+#if defined(CONFIG_NFSD_V4)
+ [4] = &nfsd_version4,
+#endif
+};
+
+#define NFSD_MINVERS 2
+#define NFSD_NRVERS (sizeof(nfsd_version)/sizeof(nfsd_version[0]))
+static struct svc_version *nfsd_versions[NFSD_NRVERS];
+
+struct svc_program nfsd_program = {
+ .pg_prog = NFS_PROGRAM, /* program number */
+ .pg_nvers = NFSD_NRVERS, /* nr of entries in nfsd_version */
+ .pg_vers = nfsd_versions, /* version table */
+ .pg_name = "nfsd", /* program name */
+ .pg_class = "nfsd", /* authentication class */
+ .pg_stats = &nfsd_svcstats, /* version table */
+ .pg_authenticate = &svc_set_client, /* export authentication */
+
+};
+
/*
* Maximum number of nfsd processes
*/
@@ -80,11 +106,12 @@
nfsd_svc(unsigned short port, int nrservs)
{
int error;
- int none_left;
+ int none_left, found_one, i;
struct list_head *victim;
lock_kernel();
- dprintk("nfsd: creating service\n");
+ dprintk("nfsd: creating service: vers 0x%x\n",
+ nfsd_versbits);
error = -EINVAL;
if (nrservs <= 0)
nrservs = 0;
@@ -99,6 +126,27 @@
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];
+ }
+
atomic_set(&nfsd_busy, 0);
error = -ENOMEM;
nfsd_serv = svc_create(&nfsd_program, NFSD_BUFSIZE);
@@ -389,28 +437,3 @@
#else
#define nfsd_acl_program_p NULL
#endif /* defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) */
-
-extern struct svc_version nfsd_version2, nfsd_version3, nfsd_version4;
-
-static struct svc_version * nfsd_version[] = {
- [2] = &nfsd_version2,
-#if defined(CONFIG_NFSD_V3)
- [3] = &nfsd_version3,
-#endif
-#if defined(CONFIG_NFSD_V4)
- [4] = &nfsd_version4,
-#endif
-};
-
-#define NFSD_NRVERS (sizeof(nfsd_version)/sizeof(nfsd_version[0]))
-struct svc_program nfsd_program = {
- .pg_next = nfsd_acl_program_p,
- .pg_prog = NFS_PROGRAM, /* program number */
- .pg_nvers = NFSD_NRVERS, /* nr of entries in nfsd_version */
- .pg_vers = nfsd_version, /* version table */
- .pg_name = "nfsd", /* program name */
- .pg_class = "nfsd", /* authentication class */
- .pg_stats = &nfsd_svcstats, /* version table */
- .pg_authenticate = &svc_set_client, /* export authentication */
-
-};
diff --git a/include/linux/nfsd/nfsd.h b/include/linux/nfsd/nfsd.h
index 6d5a24f..51c231a 100644
--- a/include/linux/nfsd/nfsd.h
+++ b/include/linux/nfsd/nfsd.h
@@ -60,7 +60,7 @@
extern struct svc_program nfsd_program;
extern struct svc_version nfsd_version2, nfsd_version3,
nfsd_version4;
-
+extern struct svc_serv *nfsd_serv;
/*
* Function prototypes.
*/
diff --git a/include/linux/nfsd/syscall.h b/include/linux/nfsd/syscall.h
index e65c9db..781efbf 100644
--- a/include/linux/nfsd/syscall.h
+++ b/include/linux/nfsd/syscall.h
@@ -39,6 +39,21 @@
#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;
@@ -120,6 +135,8 @@
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 */