WSL2-Linux-Kernel/fs/nfs/callback_proc.c

402 строки
11 KiB
C

/*
* linux/fs/nfs/callback_proc.c
*
* Copyright (C) 2004 Trond Myklebust
*
* NFSv4 callback procedures
*/
#include <linux/nfs4.h>
#include <linux/nfs_fs.h>
#include "nfs4_fs.h"
#include "callback.h"
#include "delegation.h"
#include "internal.h"
#ifdef NFS_DEBUG
#define NFSDBG_FACILITY NFSDBG_CALLBACK
#endif
__be32 nfs4_callback_getattr(struct cb_getattrargs *args, struct cb_getattrres *res)
{
struct nfs_client *clp;
struct nfs_delegation *delegation;
struct nfs_inode *nfsi;
struct inode *inode;
res->bitmap[0] = res->bitmap[1] = 0;
res->status = htonl(NFS4ERR_BADHANDLE);
clp = nfs_find_client(args->addr, 4);
if (clp == NULL)
goto out;
dprintk("NFS: GETATTR callback request from %s\n",
rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR));
inode = nfs_delegation_find_inode(clp, &args->fh);
if (inode == NULL)
goto out_putclient;
nfsi = NFS_I(inode);
down_read(&nfsi->rwsem);
delegation = nfsi->delegation;
if (delegation == NULL || (delegation->type & FMODE_WRITE) == 0)
goto out_iput;
res->size = i_size_read(inode);
res->change_attr = delegation->change_attr;
if (nfsi->npages != 0)
res->change_attr++;
res->ctime = inode->i_ctime;
res->mtime = inode->i_mtime;
res->bitmap[0] = (FATTR4_WORD0_CHANGE|FATTR4_WORD0_SIZE) &
args->bitmap[0];
res->bitmap[1] = (FATTR4_WORD1_TIME_METADATA|FATTR4_WORD1_TIME_MODIFY) &
args->bitmap[1];
res->status = 0;
out_iput:
up_read(&nfsi->rwsem);
iput(inode);
out_putclient:
nfs_put_client(clp);
out:
dprintk("%s: exit with status = %d\n", __func__, ntohl(res->status));
return res->status;
}
static int (*nfs_validate_delegation_stateid(struct nfs_client *clp))(struct nfs_delegation *, const nfs4_stateid *)
{
#if defined(CONFIG_NFS_V4_1)
if (clp->cl_minorversion > 0)
return nfs41_validate_delegation_stateid;
#endif
return nfs4_validate_delegation_stateid;
}
__be32 nfs4_callback_recall(struct cb_recallargs *args, void *dummy)
{
struct nfs_client *clp;
struct inode *inode;
__be32 res;
res = htonl(NFS4ERR_BADHANDLE);
clp = nfs_find_client(args->addr, 4);
if (clp == NULL)
goto out;
dprintk("NFS: RECALL callback request from %s\n",
rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR));
do {
struct nfs_client *prev = clp;
inode = nfs_delegation_find_inode(clp, &args->fh);
if (inode != NULL) {
/* Set up a helper thread to actually return the delegation */
switch (nfs_async_inode_return_delegation(inode, &args->stateid,
nfs_validate_delegation_stateid(clp))) {
case 0:
res = 0;
break;
case -ENOENT:
if (res != 0)
res = htonl(NFS4ERR_BAD_STATEID);
break;
default:
res = htonl(NFS4ERR_RESOURCE);
}
iput(inode);
}
clp = nfs_find_client_next(prev);
nfs_put_client(prev);
} while (clp != NULL);
out:
dprintk("%s: exit with status = %d\n", __func__, ntohl(res));
return res;
}
int nfs4_validate_delegation_stateid(struct nfs_delegation *delegation, const nfs4_stateid *stateid)
{
if (delegation == NULL || memcmp(delegation->stateid.data, stateid->data,
sizeof(delegation->stateid.data)) != 0)
return 0;
return 1;
}
#if defined(CONFIG_NFS_V4_1)
int nfs41_validate_delegation_stateid(struct nfs_delegation *delegation, const nfs4_stateid *stateid)
{
if (delegation == NULL)
return 0;
/* seqid is 4-bytes long */
if (((u32 *) &stateid->data)[0] != 0)
return 0;
if (memcmp(&delegation->stateid.data[4], &stateid->data[4],
sizeof(stateid->data)-4))
return 0;
return 1;
}
/*
* Validate the sequenceID sent by the server.
* Return success if the sequenceID is one more than what we last saw on
* this slot, accounting for wraparound. Increments the slot's sequence.
*
* We don't yet implement a duplicate request cache, instead we set the
* back channel ca_maxresponsesize_cached to zero. This is OK for now
* since we only currently implement idempotent callbacks anyway.
*
* We have a single slot backchannel at this time, so we don't bother
* checking the used_slots bit array on the table. The lower layer guarantees
* a single outstanding callback request at a time.
*/
static __be32
validate_seqid(struct nfs4_slot_table *tbl, struct cb_sequenceargs * args)
{
struct nfs4_slot *slot;
dprintk("%s enter. slotid %d seqid %d\n",
__func__, args->csa_slotid, args->csa_sequenceid);
if (args->csa_slotid > NFS41_BC_MAX_CALLBACKS)
return htonl(NFS4ERR_BADSLOT);
slot = tbl->slots + args->csa_slotid;
dprintk("%s slot table seqid: %d\n", __func__, slot->seq_nr);
/* Normal */
if (likely(args->csa_sequenceid == slot->seq_nr + 1)) {
slot->seq_nr++;
return htonl(NFS4_OK);
}
/* Replay */
if (args->csa_sequenceid == slot->seq_nr) {
dprintk("%s seqid %d is a replay\n",
__func__, args->csa_sequenceid);
/* Signal process_op to set this error on next op */
if (args->csa_cachethis == 0)
return htonl(NFS4ERR_RETRY_UNCACHED_REP);
/* The ca_maxresponsesize_cached is 0 with no DRC */
else if (args->csa_cachethis == 1)
return htonl(NFS4ERR_REP_TOO_BIG_TO_CACHE);
}
/* Wraparound */
if (args->csa_sequenceid == 1 && (slot->seq_nr + 1) == 0) {
slot->seq_nr = 1;
return htonl(NFS4_OK);
}
/* Misordered request */
return htonl(NFS4ERR_SEQ_MISORDERED);
}
/*
* Returns a pointer to a held 'struct nfs_client' that matches the server's
* address, major version number, and session ID. It is the caller's
* responsibility to release the returned reference.
*
* Returns NULL if there are no connections with sessions, or if no session
* matches the one of interest.
*/
static struct nfs_client *find_client_with_session(
const struct sockaddr *addr, u32 nfsversion,
struct nfs4_sessionid *sessionid)
{
struct nfs_client *clp;
clp = nfs_find_client(addr, 4);
if (clp == NULL)
return NULL;
do {
struct nfs_client *prev = clp;
if (clp->cl_session != NULL) {
if (memcmp(clp->cl_session->sess_id.data,
sessionid->data,
NFS4_MAX_SESSIONID_LEN) == 0) {
/* Returns a held reference to clp */
return clp;
}
}
clp = nfs_find_client_next(prev);
nfs_put_client(prev);
} while (clp != NULL);
return NULL;
}
/*
* For each referring call triple, check the session's slot table for
* a match. If the slot is in use and the sequence numbers match, the
* client is still waiting for a response to the original request.
*/
static bool referring_call_exists(struct nfs_client *clp,
uint32_t nrclists,
struct referring_call_list *rclists)
{
bool status = 0;
int i, j;
struct nfs4_session *session;
struct nfs4_slot_table *tbl;
struct referring_call_list *rclist;
struct referring_call *ref;
/*
* XXX When client trunking is implemented, this becomes
* a session lookup from within the loop
*/
session = clp->cl_session;
tbl = &session->fc_slot_table;
for (i = 0; i < nrclists; i++) {
rclist = &rclists[i];
if (memcmp(session->sess_id.data,
rclist->rcl_sessionid.data,
NFS4_MAX_SESSIONID_LEN) != 0)
continue;
for (j = 0; j < rclist->rcl_nrefcalls; j++) {
ref = &rclist->rcl_refcalls[j];
dprintk("%s: sessionid %x:%x:%x:%x sequenceid %u "
"slotid %u\n", __func__,
((u32 *)&rclist->rcl_sessionid.data)[0],
((u32 *)&rclist->rcl_sessionid.data)[1],
((u32 *)&rclist->rcl_sessionid.data)[2],
((u32 *)&rclist->rcl_sessionid.data)[3],
ref->rc_sequenceid, ref->rc_slotid);
spin_lock(&tbl->slot_tbl_lock);
status = (test_bit(ref->rc_slotid, tbl->used_slots) &&
tbl->slots[ref->rc_slotid].seq_nr ==
ref->rc_sequenceid);
spin_unlock(&tbl->slot_tbl_lock);
if (status)
goto out;
}
}
out:
return status;
}
__be32 nfs4_callback_sequence(struct cb_sequenceargs *args,
struct cb_sequenceres *res)
{
struct nfs_client *clp;
int i;
__be32 status;
status = htonl(NFS4ERR_BADSESSION);
clp = find_client_with_session(args->csa_addr, 4, &args->csa_sessionid);
if (clp == NULL)
goto out;
status = validate_seqid(&clp->cl_session->bc_slot_table, args);
if (status)
goto out_putclient;
/*
* Check for pending referring calls. If a match is found, a
* related callback was received before the response to the original
* call.
*/
if (referring_call_exists(clp, args->csa_nrclists, args->csa_rclists)) {
status = htonl(NFS4ERR_DELAY);
goto out_putclient;
}
memcpy(&res->csr_sessionid, &args->csa_sessionid,
sizeof(res->csr_sessionid));
res->csr_sequenceid = args->csa_sequenceid;
res->csr_slotid = args->csa_slotid;
res->csr_highestslotid = NFS41_BC_MAX_CALLBACKS - 1;
res->csr_target_highestslotid = NFS41_BC_MAX_CALLBACKS - 1;
out_putclient:
nfs_put_client(clp);
out:
for (i = 0; i < args->csa_nrclists; i++)
kfree(args->csa_rclists[i].rcl_refcalls);
kfree(args->csa_rclists);
if (status == htonl(NFS4ERR_RETRY_UNCACHED_REP))
res->csr_status = 0;
else
res->csr_status = status;
dprintk("%s: exit with status = %d res->csr_status %d\n", __func__,
ntohl(status), ntohl(res->csr_status));
return status;
}
__be32 nfs4_callback_recallany(struct cb_recallanyargs *args, void *dummy)
{
struct nfs_client *clp;
__be32 status;
fmode_t flags = 0;
status = htonl(NFS4ERR_OP_NOT_IN_SESSION);
clp = nfs_find_client(args->craa_addr, 4);
if (clp == NULL)
goto out;
dprintk("NFS: RECALL_ANY callback request from %s\n",
rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR));
if (test_bit(RCA4_TYPE_MASK_RDATA_DLG, (const unsigned long *)
&args->craa_type_mask))
flags = FMODE_READ;
if (test_bit(RCA4_TYPE_MASK_WDATA_DLG, (const unsigned long *)
&args->craa_type_mask))
flags |= FMODE_WRITE;
if (flags)
nfs_expire_all_delegation_types(clp, flags);
status = htonl(NFS4_OK);
out:
dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
return status;
}
/* Reduce the fore channel's max_slots to the target value */
__be32 nfs4_callback_recallslot(struct cb_recallslotargs *args, void *dummy)
{
struct nfs_client *clp;
struct nfs4_slot_table *fc_tbl;
__be32 status;
status = htonl(NFS4ERR_OP_NOT_IN_SESSION);
clp = nfs_find_client(args->crsa_addr, 4);
if (clp == NULL)
goto out;
dprintk("NFS: CB_RECALL_SLOT request from %s target max slots %d\n",
rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR),
args->crsa_target_max_slots);
fc_tbl = &clp->cl_session->fc_slot_table;
status = htonl(NFS4ERR_BAD_HIGH_SLOT);
if (args->crsa_target_max_slots > fc_tbl->max_slots ||
args->crsa_target_max_slots < 1)
goto out_putclient;
status = htonl(NFS4_OK);
if (args->crsa_target_max_slots == fc_tbl->max_slots)
goto out_putclient;
fc_tbl->target_max_slots = args->crsa_target_max_slots;
nfs41_handle_recall_slot(clp);
out_putclient:
nfs_put_client(clp); /* balance nfs_find_client */
out:
dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
return status;
}
#endif /* CONFIG_NFS_V4_1 */