kernel-ark/fs/lockd/xdr4.c
Chuck Lever 2bea90d43a SUNRPC: RPC buffer size estimates are too large
The RPC buffer size estimation logic in net/sunrpc/clnt.c always
significantly overestimates the requirements for the buffer size.
A little instrumentation demonstrated that in fact rpc_malloc was never
allocating the buffer from the mempool, but almost always called kmalloc.

To compute the size of the RPC buffer more precisely, split p_bufsiz into
two fields; one for the argument size, and one for the result size.

Then, compute the sum of the exact call and reply header sizes, and split
the RPC buffer precisely between the two.  That should keep almost all RPC
buffers within the 2KiB buffer mempool limit.

And, we can finally be rid of RPC_SLACK_SPACE!

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-04-30 22:17:10 -07:00

592 lines
14 KiB
C

/*
* linux/fs/lockd/xdr4.c
*
* XDR support for lockd and the lock client.
*
* Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
* Copyright (C) 1999, Trond Myklebust <trond.myklebust@fys.uio.no>
*/
#include <linux/types.h>
#include <linux/sched.h>
#include <linux/utsname.h>
#include <linux/nfs.h>
#include <linux/sunrpc/xdr.h>
#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/svc.h>
#include <linux/sunrpc/stats.h>
#include <linux/lockd/lockd.h>
#include <linux/lockd/sm_inter.h>
#define NLMDBG_FACILITY NLMDBG_XDR
static inline loff_t
s64_to_loff_t(__s64 offset)
{
return (loff_t)offset;
}
static inline s64
loff_t_to_s64(loff_t offset)
{
s64 res;
if (offset > NLM4_OFFSET_MAX)
res = NLM4_OFFSET_MAX;
else if (offset < -NLM4_OFFSET_MAX)
res = -NLM4_OFFSET_MAX;
else
res = offset;
return res;
}
/*
* XDR functions for basic NLM types
*/
static __be32 *
nlm4_decode_cookie(__be32 *p, struct nlm_cookie *c)
{
unsigned int len;
len = ntohl(*p++);
if(len==0)
{
c->len=4;
memset(c->data, 0, 4); /* hockeypux brain damage */
}
else if(len<=NLM_MAXCOOKIELEN)
{
c->len=len;
memcpy(c->data, p, len);
p+=XDR_QUADLEN(len);
}
else
{
printk(KERN_NOTICE
"lockd: bad cookie size %d (only cookies under %d bytes are supported.)\n", len, NLM_MAXCOOKIELEN);
return NULL;
}
return p;
}
static __be32 *
nlm4_encode_cookie(__be32 *p, struct nlm_cookie *c)
{
*p++ = htonl(c->len);
memcpy(p, c->data, c->len);
p+=XDR_QUADLEN(c->len);
return p;
}
static __be32 *
nlm4_decode_fh(__be32 *p, struct nfs_fh *f)
{
memset(f->data, 0, sizeof(f->data));
f->size = ntohl(*p++);
if (f->size > NFS_MAXFHSIZE) {
printk(KERN_NOTICE
"lockd: bad fhandle size %d (should be <=%d)\n",
f->size, NFS_MAXFHSIZE);
return NULL;
}
memcpy(f->data, p, f->size);
return p + XDR_QUADLEN(f->size);
}
static __be32 *
nlm4_encode_fh(__be32 *p, struct nfs_fh *f)
{
*p++ = htonl(f->size);
if (f->size) p[XDR_QUADLEN(f->size)-1] = 0; /* don't leak anything */
memcpy(p, f->data, f->size);
return p + XDR_QUADLEN(f->size);
}
/*
* Encode and decode owner handle
*/
static __be32 *
nlm4_decode_oh(__be32 *p, struct xdr_netobj *oh)
{
return xdr_decode_netobj(p, oh);
}
static __be32 *
nlm4_encode_oh(__be32 *p, struct xdr_netobj *oh)
{
return xdr_encode_netobj(p, oh);
}
static __be32 *
nlm4_decode_lock(__be32 *p, struct nlm_lock *lock)
{
struct file_lock *fl = &lock->fl;
__s64 len, start, end;
if (!(p = xdr_decode_string_inplace(p, &lock->caller,
&lock->len, NLM_MAXSTRLEN))
|| !(p = nlm4_decode_fh(p, &lock->fh))
|| !(p = nlm4_decode_oh(p, &lock->oh)))
return NULL;
lock->svid = ntohl(*p++);
locks_init_lock(fl);
fl->fl_owner = current->files;
fl->fl_pid = (pid_t)lock->svid;
fl->fl_flags = FL_POSIX;
fl->fl_type = F_RDLCK; /* as good as anything else */
p = xdr_decode_hyper(p, &start);
p = xdr_decode_hyper(p, &len);
end = start + len - 1;
fl->fl_start = s64_to_loff_t(start);
if (len == 0 || end < 0)
fl->fl_end = OFFSET_MAX;
else
fl->fl_end = s64_to_loff_t(end);
return p;
}
/*
* Encode a lock as part of an NLM call
*/
static __be32 *
nlm4_encode_lock(__be32 *p, struct nlm_lock *lock)
{
struct file_lock *fl = &lock->fl;
__s64 start, len;
if (!(p = xdr_encode_string(p, lock->caller))
|| !(p = nlm4_encode_fh(p, &lock->fh))
|| !(p = nlm4_encode_oh(p, &lock->oh)))
return NULL;
if (fl->fl_start > NLM4_OFFSET_MAX
|| (fl->fl_end > NLM4_OFFSET_MAX && fl->fl_end != OFFSET_MAX))
return NULL;
*p++ = htonl(lock->svid);
start = loff_t_to_s64(fl->fl_start);
if (fl->fl_end == OFFSET_MAX)
len = 0;
else
len = loff_t_to_s64(fl->fl_end - fl->fl_start + 1);
p = xdr_encode_hyper(p, start);
p = xdr_encode_hyper(p, len);
return p;
}
/*
* Encode result of a TEST/TEST_MSG call
*/
static __be32 *
nlm4_encode_testres(__be32 *p, struct nlm_res *resp)
{
s64 start, len;
dprintk("xdr: before encode_testres (p %p resp %p)\n", p, resp);
if (!(p = nlm4_encode_cookie(p, &resp->cookie)))
return NULL;
*p++ = resp->status;
if (resp->status == nlm_lck_denied) {
struct file_lock *fl = &resp->lock.fl;
*p++ = (fl->fl_type == F_RDLCK)? xdr_zero : xdr_one;
*p++ = htonl(resp->lock.svid);
/* Encode owner handle. */
if (!(p = xdr_encode_netobj(p, &resp->lock.oh)))
return NULL;
start = loff_t_to_s64(fl->fl_start);
if (fl->fl_end == OFFSET_MAX)
len = 0;
else
len = loff_t_to_s64(fl->fl_end - fl->fl_start + 1);
p = xdr_encode_hyper(p, start);
p = xdr_encode_hyper(p, len);
dprintk("xdr: encode_testres (status %u pid %d type %d start %Ld end %Ld)\n",
resp->status, (int)resp->lock.svid, fl->fl_type,
(long long)fl->fl_start, (long long)fl->fl_end);
}
dprintk("xdr: after encode_testres (p %p resp %p)\n", p, resp);
return p;
}
/*
* First, the server side XDR functions
*/
int
nlm4svc_decode_testargs(struct svc_rqst *rqstp, __be32 *p, nlm_args *argp)
{
u32 exclusive;
if (!(p = nlm4_decode_cookie(p, &argp->cookie)))
return 0;
exclusive = ntohl(*p++);
if (!(p = nlm4_decode_lock(p, &argp->lock)))
return 0;
if (exclusive)
argp->lock.fl.fl_type = F_WRLCK;
return xdr_argsize_check(rqstp, p);
}
int
nlm4svc_encode_testres(struct svc_rqst *rqstp, __be32 *p, struct nlm_res *resp)
{
if (!(p = nlm4_encode_testres(p, resp)))
return 0;
return xdr_ressize_check(rqstp, p);
}
int
nlm4svc_decode_lockargs(struct svc_rqst *rqstp, __be32 *p, nlm_args *argp)
{
u32 exclusive;
if (!(p = nlm4_decode_cookie(p, &argp->cookie)))
return 0;
argp->block = ntohl(*p++);
exclusive = ntohl(*p++);
if (!(p = nlm4_decode_lock(p, &argp->lock)))
return 0;
if (exclusive)
argp->lock.fl.fl_type = F_WRLCK;
argp->reclaim = ntohl(*p++);
argp->state = ntohl(*p++);
argp->monitor = 1; /* monitor client by default */
return xdr_argsize_check(rqstp, p);
}
int
nlm4svc_decode_cancargs(struct svc_rqst *rqstp, __be32 *p, nlm_args *argp)
{
u32 exclusive;
if (!(p = nlm4_decode_cookie(p, &argp->cookie)))
return 0;
argp->block = ntohl(*p++);
exclusive = ntohl(*p++);
if (!(p = nlm4_decode_lock(p, &argp->lock)))
return 0;
if (exclusive)
argp->lock.fl.fl_type = F_WRLCK;
return xdr_argsize_check(rqstp, p);
}
int
nlm4svc_decode_unlockargs(struct svc_rqst *rqstp, __be32 *p, nlm_args *argp)
{
if (!(p = nlm4_decode_cookie(p, &argp->cookie))
|| !(p = nlm4_decode_lock(p, &argp->lock)))
return 0;
argp->lock.fl.fl_type = F_UNLCK;
return xdr_argsize_check(rqstp, p);
}
int
nlm4svc_decode_shareargs(struct svc_rqst *rqstp, __be32 *p, nlm_args *argp)
{
struct nlm_lock *lock = &argp->lock;
memset(lock, 0, sizeof(*lock));
locks_init_lock(&lock->fl);
lock->svid = ~(u32) 0;
lock->fl.fl_pid = (pid_t)lock->svid;
if (!(p = nlm4_decode_cookie(p, &argp->cookie))
|| !(p = xdr_decode_string_inplace(p, &lock->caller,
&lock->len, NLM_MAXSTRLEN))
|| !(p = nlm4_decode_fh(p, &lock->fh))
|| !(p = nlm4_decode_oh(p, &lock->oh)))
return 0;
argp->fsm_mode = ntohl(*p++);
argp->fsm_access = ntohl(*p++);
return xdr_argsize_check(rqstp, p);
}
int
nlm4svc_encode_shareres(struct svc_rqst *rqstp, __be32 *p, struct nlm_res *resp)
{
if (!(p = nlm4_encode_cookie(p, &resp->cookie)))
return 0;
*p++ = resp->status;
*p++ = xdr_zero; /* sequence argument */
return xdr_ressize_check(rqstp, p);
}
int
nlm4svc_encode_res(struct svc_rqst *rqstp, __be32 *p, struct nlm_res *resp)
{
if (!(p = nlm4_encode_cookie(p, &resp->cookie)))
return 0;
*p++ = resp->status;
return xdr_ressize_check(rqstp, p);
}
int
nlm4svc_decode_notify(struct svc_rqst *rqstp, __be32 *p, struct nlm_args *argp)
{
struct nlm_lock *lock = &argp->lock;
if (!(p = xdr_decode_string_inplace(p, &lock->caller,
&lock->len, NLM_MAXSTRLEN)))
return 0;
argp->state = ntohl(*p++);
return xdr_argsize_check(rqstp, p);
}
int
nlm4svc_decode_reboot(struct svc_rqst *rqstp, __be32 *p, struct nlm_reboot *argp)
{
if (!(p = xdr_decode_string_inplace(p, &argp->mon, &argp->len, SM_MAXSTRLEN)))
return 0;
argp->state = ntohl(*p++);
/* Preserve the address in network byte order */
argp->addr = *p++;
argp->vers = *p++;
argp->proto = *p++;
return xdr_argsize_check(rqstp, p);
}
int
nlm4svc_decode_res(struct svc_rqst *rqstp, __be32 *p, struct nlm_res *resp)
{
if (!(p = nlm4_decode_cookie(p, &resp->cookie)))
return 0;
resp->status = *p++;
return xdr_argsize_check(rqstp, p);
}
int
nlm4svc_decode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
{
return xdr_argsize_check(rqstp, p);
}
int
nlm4svc_encode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
{
return xdr_ressize_check(rqstp, p);
}
/*
* Now, the client side XDR functions
*/
#ifdef NLMCLNT_SUPPORT_SHARES
static int
nlm4clt_decode_void(struct rpc_rqst *req, __be32 *p, void *ptr)
{
return 0;
}
#endif
static int
nlm4clt_encode_testargs(struct rpc_rqst *req, __be32 *p, nlm_args *argp)
{
struct nlm_lock *lock = &argp->lock;
if (!(p = nlm4_encode_cookie(p, &argp->cookie)))
return -EIO;
*p++ = (lock->fl.fl_type == F_WRLCK)? xdr_one : xdr_zero;
if (!(p = nlm4_encode_lock(p, lock)))
return -EIO;
req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
return 0;
}
static int
nlm4clt_decode_testres(struct rpc_rqst *req, __be32 *p, struct nlm_res *resp)
{
if (!(p = nlm4_decode_cookie(p, &resp->cookie)))
return -EIO;
resp->status = *p++;
if (resp->status == nlm_lck_denied) {
struct file_lock *fl = &resp->lock.fl;
u32 excl;
s64 start, end, len;
memset(&resp->lock, 0, sizeof(resp->lock));
locks_init_lock(fl);
excl = ntohl(*p++);
resp->lock.svid = ntohl(*p++);
fl->fl_pid = (pid_t)resp->lock.svid;
if (!(p = nlm4_decode_oh(p, &resp->lock.oh)))
return -EIO;
fl->fl_flags = FL_POSIX;
fl->fl_type = excl? F_WRLCK : F_RDLCK;
p = xdr_decode_hyper(p, &start);
p = xdr_decode_hyper(p, &len);
end = start + len - 1;
fl->fl_start = s64_to_loff_t(start);
if (len == 0 || end < 0)
fl->fl_end = OFFSET_MAX;
else
fl->fl_end = s64_to_loff_t(end);
}
return 0;
}
static int
nlm4clt_encode_lockargs(struct rpc_rqst *req, __be32 *p, nlm_args *argp)
{
struct nlm_lock *lock = &argp->lock;
if (!(p = nlm4_encode_cookie(p, &argp->cookie)))
return -EIO;
*p++ = argp->block? xdr_one : xdr_zero;
*p++ = (lock->fl.fl_type == F_WRLCK)? xdr_one : xdr_zero;
if (!(p = nlm4_encode_lock(p, lock)))
return -EIO;
*p++ = argp->reclaim? xdr_one : xdr_zero;
*p++ = htonl(argp->state);
req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
return 0;
}
static int
nlm4clt_encode_cancargs(struct rpc_rqst *req, __be32 *p, nlm_args *argp)
{
struct nlm_lock *lock = &argp->lock;
if (!(p = nlm4_encode_cookie(p, &argp->cookie)))
return -EIO;
*p++ = argp->block? xdr_one : xdr_zero;
*p++ = (lock->fl.fl_type == F_WRLCK)? xdr_one : xdr_zero;
if (!(p = nlm4_encode_lock(p, lock)))
return -EIO;
req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
return 0;
}
static int
nlm4clt_encode_unlockargs(struct rpc_rqst *req, __be32 *p, nlm_args *argp)
{
struct nlm_lock *lock = &argp->lock;
if (!(p = nlm4_encode_cookie(p, &argp->cookie)))
return -EIO;
if (!(p = nlm4_encode_lock(p, lock)))
return -EIO;
req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
return 0;
}
static int
nlm4clt_encode_res(struct rpc_rqst *req, __be32 *p, struct nlm_res *resp)
{
if (!(p = nlm4_encode_cookie(p, &resp->cookie)))
return -EIO;
*p++ = resp->status;
req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
return 0;
}
static int
nlm4clt_encode_testres(struct rpc_rqst *req, __be32 *p, struct nlm_res *resp)
{
if (!(p = nlm4_encode_testres(p, resp)))
return -EIO;
req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
return 0;
}
static int
nlm4clt_decode_res(struct rpc_rqst *req, __be32 *p, struct nlm_res *resp)
{
if (!(p = nlm4_decode_cookie(p, &resp->cookie)))
return -EIO;
resp->status = *p++;
return 0;
}
#if (NLMCLNT_OHSIZE > XDR_MAX_NETOBJ)
# error "NLM host name cannot be larger than XDR_MAX_NETOBJ!"
#endif
#if (NLMCLNT_OHSIZE > NLM_MAXSTRLEN)
# error "NLM host name cannot be larger than NLM's maximum string length!"
#endif
/*
* Buffer requirements for NLM
*/
#define NLM4_void_sz 0
#define NLM4_cookie_sz 1+XDR_QUADLEN(NLM_MAXCOOKIELEN)
#define NLM4_caller_sz 1+XDR_QUADLEN(NLMCLNT_OHSIZE)
#define NLM4_owner_sz 1+XDR_QUADLEN(NLMCLNT_OHSIZE)
#define NLM4_fhandle_sz 1+XDR_QUADLEN(NFS3_FHSIZE)
#define NLM4_lock_sz 5+NLM4_caller_sz+NLM4_owner_sz+NLM4_fhandle_sz
#define NLM4_holder_sz 6+NLM4_owner_sz
#define NLM4_testargs_sz NLM4_cookie_sz+1+NLM4_lock_sz
#define NLM4_lockargs_sz NLM4_cookie_sz+4+NLM4_lock_sz
#define NLM4_cancargs_sz NLM4_cookie_sz+2+NLM4_lock_sz
#define NLM4_unlockargs_sz NLM4_cookie_sz+NLM4_lock_sz
#define NLM4_testres_sz NLM4_cookie_sz+1+NLM4_holder_sz
#define NLM4_res_sz NLM4_cookie_sz+1
#define NLM4_norep_sz 0
/*
* For NLM, a void procedure really returns nothing
*/
#define nlm4clt_decode_norep NULL
#define PROC(proc, argtype, restype) \
[NLMPROC_##proc] = { \
.p_proc = NLMPROC_##proc, \
.p_encode = (kxdrproc_t) nlm4clt_encode_##argtype, \
.p_decode = (kxdrproc_t) nlm4clt_decode_##restype, \
.p_arglen = NLM4_##argtype##_sz, \
.p_replen = NLM4_##restype##_sz, \
.p_statidx = NLMPROC_##proc, \
.p_name = #proc, \
}
static struct rpc_procinfo nlm4_procedures[] = {
PROC(TEST, testargs, testres),
PROC(LOCK, lockargs, res),
PROC(CANCEL, cancargs, res),
PROC(UNLOCK, unlockargs, res),
PROC(GRANTED, testargs, res),
PROC(TEST_MSG, testargs, norep),
PROC(LOCK_MSG, lockargs, norep),
PROC(CANCEL_MSG, cancargs, norep),
PROC(UNLOCK_MSG, unlockargs, norep),
PROC(GRANTED_MSG, testargs, norep),
PROC(TEST_RES, testres, norep),
PROC(LOCK_RES, res, norep),
PROC(CANCEL_RES, res, norep),
PROC(UNLOCK_RES, res, norep),
PROC(GRANTED_RES, res, norep),
#ifdef NLMCLNT_SUPPORT_SHARES
PROC(SHARE, shareargs, shareres),
PROC(UNSHARE, shareargs, shareres),
PROC(NM_LOCK, lockargs, res),
PROC(FREE_ALL, notify, void),
#endif
};
struct rpc_version nlm_version4 = {
.number = 4,
.nrprocs = 24,
.procs = nlm4_procedures,
};