[PATCH] knfsd: Allow max size of NFSd payload to be configured

The max possible is the maximum RPC payload.  The default depends on amount of
total memory.

The value can be set within reason as long as no nfsd threads are currently
running.  The value can also be ready, allowing the default to be determined
after nfsd has started.

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 6c2ddfed2cfc40b397fed9737712cc14f01872d1..39aed901514b0c34d30cb468b1a8aabadc33b2e8 100644 (file)
--- a/fs/nfsd/nfsctl.c
+++ b/fs/nfsd/nfsctl.c
@@ -57,6 +57,7 @@ enum {
        NFSD_Pool_Threads,
        NFSD_Versions,
        NFSD_Ports,
+       NFSD_MaxBlkSize,
        /*
         * The below MUST come last.  Otherwise we leave a hole in nfsd_files[]
         * with !CONFIG_NFSD_V4 and simple_fill_super() goes oops
@@ -82,6 +83,7 @@ static ssize_t write_threads(struct file *file, char *buf, size_t size);
 static ssize_t write_pool_threads(struct file *file, char *buf, size_t size);
 static ssize_t write_versions(struct file *file, char *buf, size_t size);
 static ssize_t write_ports(struct file *file, char *buf, size_t size);
+static ssize_t write_maxblksize(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);
@@ -100,6 +102,7 @@ static ssize_t (*write_op[])(struct file *, char *, size_t) = {
        [NFSD_Pool_Threads] = write_pool_threads,
        [NFSD_Versions] = write_versions,
        [NFSD_Ports] = write_ports,
+       [NFSD_MaxBlkSize] = write_maxblksize,
 #ifdef CONFIG_NFSD_V4
        [NFSD_Leasetime] = write_leasetime,
        [NFSD_RecoveryDir] = write_recoverydir,
@@ -555,6 +558,35 @@ static ssize_t write_ports(struct file *file, char *buf, size_t size)
        return -EINVAL;
 }
 
+int nfsd_max_blksize;
+
+static ssize_t write_maxblksize(struct file *file, char *buf, size_t size)
+{
+       char *mesg = buf;
+       if (size > 0) {
+               int bsize;
+               int rv = get_int(&mesg, &bsize);
+               if (rv)
+                       return rv;
+               /* force bsize into allowed range and
+                * required alignment.
+                */
+               if (bsize < 1024)
+                       bsize = 1024;
+               if (bsize > NFSSVC_MAXBLKSIZE)
+                       bsize = NFSSVC_MAXBLKSIZE;
+               bsize &= ~(1024-1);
+               lock_kernel();
+               if (nfsd_serv && nfsd_serv->sv_nrthreads) {
+                       unlock_kernel();
+                       return -EBUSY;
+               }
+               nfsd_max_blksize = bsize;
+               unlock_kernel();
+       }
+       return sprintf(buf, "%d\n", nfsd_max_blksize);
+}
+
 #ifdef CONFIG_NFSD_V4
 extern time_t nfs4_leasetime(void);
 
@@ -620,6 +652,7 @@ static int nfsd_fill_super(struct super_block * sb, void * data, int silent)
                [NFSD_Pool_Threads] = {"pool_threads", &transaction_ops, S_IWUSR|S_IRUSR},
                [NFSD_Versions] = {"versions", &transaction_ops, S_IWUSR|S_IRUSR},
                [NFSD_Ports] = {"portlist", &transaction_ops, S_IWUSR|S_IRUGO},
+               [NFSD_MaxBlkSize] = {"max_block_size", &transaction_ops, S_IWUSR|S_IRUGO},
 #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 19443056ec301a94df4db864d617fac80a0f0fa5..0603baad54266708f9e336669c0158d791845a50 100644 (file)
--- a/fs/nfsd/nfssvc.c
+++ b/fs/nfsd/nfssvc.c
@@ -198,9 +198,26 @@ int nfsd_create_serv(void)
                unlock_kernel();
                return 0;
        }
+       if (nfsd_max_blksize == 0) {
+               /* choose a suitable default */
+               struct sysinfo i;
+               si_meminfo(&i);
+               /* Aim for 1/4096 of memory per thread
+                * This gives 1MB on 4Gig machines
+                * But only uses 32K on 128M machines.
+                * Bottom out at 8K on 32M and smaller.
+                * Of course, this is only a default.
+                */
+               nfsd_max_blksize = NFSSVC_MAXBLKSIZE;
+               i.totalram >>= 12;
+               while (nfsd_max_blksize > i.totalram &&
+                      nfsd_max_blksize >= 8*1024*2)
+                       nfsd_max_blksize /= 2;
+       }
 
        atomic_set(&nfsd_busy, 0);
-       nfsd_serv = svc_create_pooled(&nfsd_program, NFSD_BUFSIZE,
+       nfsd_serv = svc_create_pooled(&nfsd_program,
+                                     NFSD_BUFSIZE - NFSSVC_MAXBLKSIZE + nfsd_max_blksize,
                                      nfsd_last_thread,
                                      nfsd, SIG_NOCLEAN, THIS_MODULE);
        if (nfsd_serv == NULL)

diff --git a/include/linux/nfsd/const.h b/include/linux/nfsd/const.h
index adbddf007898d697b4789626d336d8b733a8788f..f478066f9cd5da67c203ce84783c89745d05fda0 100644 (file)
--- a/include/linux/nfsd/const.h
+++ b/include/linux/nfsd/const.h
@@ -21,9 +21,9 @@
 #define NFSSVC_MAXVERS         3
 
 /*
- * Maximum blocksize supported by daemon currently at 32K
+ * Maximum blocksizes supported by daemon under various circumstances.
  */
-#define NFSSVC_MAXBLKSIZE      (32*1024)
+#define NFSSVC_MAXBLKSIZE      RPCSVC_MAXPAYLOAD
 /* NFSv2 is limited by the protocol specification, see RFC 1094 */
 #define NFSSVC_MAXBLKSIZE_V2   (8*1024)
 

diff --git a/include/linux/nfsd/nfsd.h b/include/linux/nfsd/nfsd.h
index e1dbc86c270b874e00ede638eeb8f64155d22872..259841bb2f6c7628b5db512d533b514655ba56f7 100644 (file)
--- a/include/linux/nfsd/nfsd.h
+++ b/include/linux/nfsd/nfsd.h
@@ -145,6 +145,7 @@ int nfsd_vers(int vers, enum vers_op change);
 void nfsd_reset_versions(void);
 int nfsd_create_serv(void);
 
+extern int nfsd_max_blksize;
 
 /* 
  * NFSv4 State