On 2010-09-21 23:58, Jeff Layton wrote:
> On Tue, 21 Sep 2010 16:46:21 -0400
> Trond Myklebust <trond.myklebust@xxxxxxxxxx> wrote:
>
>> On Tue, 2010-09-21 at 16:24 -0400, J. Bruce Fields wrote:
>>> On Tue, Sep 21, 2010 at 04:00:32PM -0400, Trond Myklebust wrote:
>>>> On Tue, 2010-09-21 at 15:36 -0400, Trond Myklebust wrote:
>>>>> On Tue, 2010-09-21 at 15:20 -0400, J. Bruce Fields wrote:
>>>>>> All I need to do is mount nfs4.1 and run cthon -s. The last output I
>>>>>> see from the test is:
>>>>>>
>>>>>> check for proper open/unlink operation
>>>>>> nfsjunk files before unlink:
>>>>>>
>>>>>
>>>>> Oh... I bet I see what it is.
>>>>>
>>>>> It's that damned res->sr_slotid = NFS4_MAX_SLOT_TABLE and related
>>>>> initialisation junk that's biting us in the arse again...
>>>>>
>>>>> I'll fix it...
>>>>
>>>> Does this work?
>>>
>>> Yup.
>>
>> It seems to fix things for me too... Once you mentioned NFSv4.1 it was
>> easy to reproduce the bug.
>>
>> OK. I'll merge these into nfs-for-2.6.37...
>
> Thanks for fixing it. I should have mentioned that the 4.1 parts were
> written using the "cargo-cult" programming method of copying what
> unlink does, and that they needed careful review. Mea culpa!
>
I still hate it that the sr_slotid requires explicit, non-trivial initialization.
Once upon a time, the equivalent of sr_slotid used to be a pointer to
struct slot. Using a pointer, implicitly initialized to NULL is significantly
more straight forward as in the patch below.
(passes cthon tests over your nfs-for-2.6.37 branch + the patch I
sent earlier that fixes __put_nfs_open_context. w/o it I readily reproduce the
crash reported on this thread)
>From 50221fb5bd8fbd46f6cabe1fc795db7efc71bff7 Mon Sep 17 00:00:00 2001
From: Benny Halevy <bhalevy@xxxxxxxxxxx>
Date: Thu, 23 Sep 2010 19:08:21 +0200
Subject: [PATCH] NFSv4.1: keep seq_res.sr_slot as pointer rather than an index
Having to explicitly initialize sr_slotid to NFS4_MAX_SLOT_TABLE
resulted in numerous bugs. Keeping the current slot as a pointer
to the slot table is more straight forward and robust as it's
implicitly set up to NULL wherever the seq_res member is initialized
to zeroes.
Signed-off-by: Benny Halevy <bhalevy@xxxxxxxxxxx>
---
fs/nfs/nfs4proc.c | 52 +++++++++++++++++++----------------------------
fs/nfs/nfs4xdr.c | 6 +---
fs/nfs/read.c | 1 -
fs/nfs/unlink.c | 3 +-
fs/nfs/write.c | 2 -
include/linux/nfs_xdr.h | 2 +-
6 files changed, 25 insertions(+), 41 deletions(-)
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 72aa706..7f8cc33 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -334,10 +334,12 @@ static void renew_lease(const struct nfs_server *server, unsigned long timestamp
* Must be called while holding tbl->slot_tbl_lock
*/
static void
-nfs4_free_slot(struct nfs4_slot_table *tbl, u8 free_slotid)
+nfs4_free_slot(struct nfs4_slot_table *tbl, struct nfs4_slot *free_slot)
{
+ int free_slotid = free_slot - tbl->slots;
int slotid = free_slotid;
+ BUG_ON(slotid < 0 || slotid >= NFS4_MAX_SLOT_TABLE);
/* clear used bit in bitmap */
__clear_bit(slotid, tbl->used_slots);
@@ -379,7 +381,7 @@ static void nfs41_sequence_free_slot(struct nfs4_sequence_res *res)
struct nfs4_slot_table *tbl;
tbl = &res->sr_session->fc_slot_table;
- if (res->sr_slotid == NFS4_MAX_SLOT_TABLE) {
+ if (!res->sr_slot) {
/* just wake up the next guy waiting since
* we may have not consumed a slot after all */
dprintk("%s: No slot\n", __func__);
@@ -387,17 +389,15 @@ static void nfs41_sequence_free_slot(struct nfs4_sequence_res *res)
}
spin_lock(&tbl->slot_tbl_lock);
- nfs4_free_slot(tbl, res->sr_slotid);
+ nfs4_free_slot(tbl, res->sr_slot);
nfs41_check_drain_session_complete(res->sr_session);
spin_unlock(&tbl->slot_tbl_lock);
- res->sr_slotid = NFS4_MAX_SLOT_TABLE;
+ res->sr_slot = NULL;
}
static int nfs41_sequence_done(struct rpc_task *task, struct nfs4_sequence_res *res)
{
unsigned long timestamp;
- struct nfs4_slot_table *tbl;
- struct nfs4_slot *slot;
struct nfs_client *clp;
/*
@@ -410,17 +410,14 @@ static int nfs41_sequence_done(struct rpc_task *task, struct nfs4_sequence_res *
res->sr_status = NFS_OK;
/* -ERESTARTSYS can result in skipping nfs41_sequence_setup */
- if (res->sr_slotid == NFS4_MAX_SLOT_TABLE)
+ if (!res->sr_slot)
goto out;
- tbl = &res->sr_session->fc_slot_table;
- slot = tbl->slots + res->sr_slotid;
-
/* Check the SEQUENCE operation status */
switch (res->sr_status) {
case 0:
/* Update the slot's sequence and clientid lease timer */
- ++slot->seq_nr;
+ ++res->sr_slot->seq_nr;
timestamp = res->sr_renewal_time;
clp = res->sr_session->clp;
do_renew_lease(clp, timestamp);
@@ -433,12 +430,14 @@ static int nfs41_sequence_done(struct rpc_task *task, struct nfs4_sequence_res *
* returned NFS4ERR_DELAY as per Section 2.10.6.2
* of RFC5661.
*/
- dprintk("%s: slot=%d seq=%d: Operation in progress\n",
- __func__, res->sr_slotid, slot->seq_nr);
+ dprintk("%s: slot=%ld seq=%d: Operation in progress\n",
+ __func__,
+ res->sr_slot - res->sr_session->fc_slot_table.slots,
+ res->sr_slot->seq_nr);
goto out_retry;
default:
/* Just update the slot sequence no. */
- ++slot->seq_nr;
+ ++res->sr_slot->seq_nr;
}
out:
/* The session may be reset by one of the error handlers. */
@@ -505,10 +504,9 @@ static int nfs41_setup_sequence(struct nfs4_session *session,
dprintk("--> %s\n", __func__);
/* slot already allocated? */
- if (res->sr_slotid != NFS4_MAX_SLOT_TABLE)
+ if (res->sr_slot != NULL)
return 0;
- res->sr_slotid = NFS4_MAX_SLOT_TABLE;
tbl = &session->fc_slot_table;
spin_lock(&tbl->slot_tbl_lock);
@@ -550,7 +548,7 @@ static int nfs41_setup_sequence(struct nfs4_session *session,
dprintk("<-- %s slotid=%d seqid=%d\n", __func__, slotid, slot->seq_nr);
res->sr_session = session;
- res->sr_slotid = slotid;
+ res->sr_slot = slot;
res->sr_renewal_time = jiffies;
res->sr_status_flags = 0;
/*
@@ -576,8 +574,9 @@ int nfs4_setup_sequence(const struct nfs_server *server,
goto out;
}
- dprintk("--> %s clp %p session %p sr_slotid %d\n",
- __func__, session->clp, session, res->sr_slotid);
+ dprintk("--> %s clp %p session %p sr_slot %ld\n",
+ __func__, session->clp, session, res->sr_slot ?
+ res->sr_slot - session->fc_slot_table.slots : -1);
ret = nfs41_setup_sequence(session, args, res, cache_reply,
task);
@@ -650,7 +649,7 @@ static int nfs4_call_sync_sequence(struct nfs_server *server,
.callback_data = &data
};
- res->sr_slotid = NFS4_MAX_SLOT_TABLE;
+ res->sr_slot = NULL;
if (privileged)
task_setup.callback_ops = &nfs41_call_priv_sync_ops;
task = rpc_run_task(&task_setup);
@@ -735,7 +734,6 @@ static void nfs4_init_opendata_res(struct nfs4_opendata *p)
p->o_res.server = p->o_arg.server;
nfs_fattr_init(&p->f_attr);
nfs_fattr_init(&p->dir_attr);
- p->o_res.seq_res.sr_slotid = NFS4_MAX_SLOT_TABLE;
}
static struct nfs4_opendata *nfs4_opendata_alloc(struct path *path,
@@ -1975,7 +1973,6 @@ int nfs4_do_close(struct path *path, struct nfs4_state *state, gfp_t gfp_mask, i
calldata->res.fattr = &calldata->fattr;
calldata->res.seqid = calldata->arg.seqid;
calldata->res.server = server;
- calldata->res.seq_res.sr_slotid = NFS4_MAX_SLOT_TABLE;
path_get(path);
calldata->path = *path;
@@ -2550,7 +2547,7 @@ static void nfs4_proc_unlink_setup(struct rpc_message *msg, struct inode *dir)
args->bitmask = server->cache_consistency_bitmask;
res->server = server;
- res->seq_res.sr_slotid = NFS4_MAX_SLOT_TABLE;
+ res->seq_res.sr_slot = NULL;
msg->rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_REMOVE];
}
@@ -2576,7 +2573,6 @@ static void nfs4_proc_rename_setup(struct rpc_message *msg, struct inode *dir)
msg->rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_RENAME];
arg->bitmask = server->attr_bitmask;
res->server = server;
- res->seq_res.sr_slotid = NFS4_MAX_SLOT_TABLE;
}
static int nfs4_proc_rename_done(struct rpc_task *task, struct inode *old_dir,
@@ -3646,7 +3642,6 @@ static int _nfs4_proc_delegreturn(struct inode *inode, struct rpc_cred *cred, co
memcpy(&data->stateid, stateid, sizeof(data->stateid));
data->res.fattr = &data->fattr;
data->res.server = server;
- data->res.seq_res.sr_slotid = NFS4_MAX_SLOT_TABLE;
nfs_fattr_init(data->res.fattr);
data->timestamp = jiffies;
data->rpc_status = 0;
@@ -3799,7 +3794,6 @@ static struct nfs4_unlockdata *nfs4_alloc_unlockdata(struct file_lock *fl,
p->arg.fl = &p->fl;
p->arg.seqid = seqid;
p->res.seqid = seqid;
- p->res.seq_res.sr_slotid = NFS4_MAX_SLOT_TABLE;
p->arg.stateid = &lsp->ls_stateid;
p->lsp = lsp;
atomic_inc(&lsp->ls_count);
@@ -3979,7 +3973,6 @@ static struct nfs4_lockdata *nfs4_alloc_lockdata(struct file_lock *fl,
p->arg.lock_owner.clientid = server->nfs_client->cl_clientid;
p->arg.lock_owner.id = lsp->ls_id.id;
p->res.lock_seqid = p->arg.lock_seqid;
- p->res.seq_res.sr_slotid = NFS4_MAX_SLOT_TABLE;
p->lsp = lsp;
p->server = server;
atomic_inc(&lsp->ls_count);
@@ -4612,7 +4605,6 @@ int nfs4_proc_get_lease_time(struct nfs_client *clp, struct nfs_fsinfo *fsinfo)
};
int status;
- res.lr_seq_res.sr_slotid = NFS4_MAX_SLOT_TABLE;
dprintk("--> %s\n", __func__);
task = rpc_run_task(&task_setup);
@@ -5105,12 +5097,11 @@ static struct rpc_task *_nfs41_proc_sequence(struct nfs_client *clp, struct rpc_
if (!atomic_inc_not_zero(&clp->cl_count))
return ERR_PTR(-EIO);
- calldata = kmalloc(sizeof(*calldata), GFP_NOFS);
+ calldata = kzalloc(sizeof(*calldata), GFP_NOFS);
if (calldata == NULL) {
nfs_put_client(clp);
return ERR_PTR(-ENOMEM);
}
- calldata->res.sr_slotid = NFS4_MAX_SLOT_TABLE;
msg.rpc_argp = &calldata->args;
msg.rpc_resp = &calldata->res;
calldata->clp = clp;
@@ -5242,7 +5233,6 @@ static int nfs41_proc_reclaim_complete(struct nfs_client *clp)
goto out;
calldata->clp = clp;
calldata->arg.one_fs = 0;
- calldata->res.seq_res.sr_slotid = NFS4_MAX_SLOT_TABLE;
msg.rpc_argp = &calldata->arg;
msg.rpc_resp = &calldata->res;
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index b0bd7ef..ccf09c4 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -4668,7 +4668,6 @@ static int decode_sequence(struct xdr_stream *xdr,
struct rpc_rqst *rqstp)
{
#if defined(CONFIG_NFS_V4_1)
- struct nfs4_slot *slot;
struct nfs4_sessionid id;
u32 dummy;
int status;
@@ -4700,15 +4699,14 @@ static int decode_sequence(struct xdr_stream *xdr,
goto out_overflow;
/* seqid */
- slot = &res->sr_session->fc_slot_table.slots[res->sr_slotid];
dummy = be32_to_cpup(p++);
- if (dummy != slot->seq_nr) {
+ if (dummy != res->sr_slot->seq_nr) {
dprintk("%s Invalid sequence number\n", __func__);
goto out_err;
}
/* slot id */
dummy = be32_to_cpup(p++);
- if (dummy != res->sr_slotid) {
+ if (dummy != res->sr_slot - res->sr_session->fc_slot_table.slots) {
dprintk("%s Invalid slot id\n", __func__);
goto out_err;
}
diff --git a/fs/nfs/read.c b/fs/nfs/read.c
index 87adc27..79859c8 100644
--- a/fs/nfs/read.c
+++ b/fs/nfs/read.c
@@ -46,7 +46,6 @@ struct nfs_read_data *nfs_readdata_alloc(unsigned int pagecount)
memset(p, 0, sizeof(*p));
INIT_LIST_HEAD(&p->pages);
p->npages = pagecount;
- p->res.seq_res.sr_slotid = NFS4_MAX_SLOT_TABLE;
if (pagecount <= ARRAY_SIZE(p->page_array))
p->pagevec = p->page_array;
else {
diff --git a/fs/nfs/unlink.c b/fs/nfs/unlink.c
index 47530aa..9a16bad 100644
--- a/fs/nfs/unlink.c
+++ b/fs/nfs/unlink.c
@@ -262,7 +262,6 @@ nfs_async_unlink(struct inode *dir, struct dentry *dentry)
status = PTR_ERR(data->cred);
goto out_free;
}
- data->res.seq_res.sr_slotid = NFS4_MAX_SLOT_TABLE;
data->res.dir_attr = &data->dir_attr;
status = -EBUSY;
@@ -427,7 +426,7 @@ nfs_async_rename(struct inode *old_dir, struct inode *new_dir,
.flags = RPC_TASK_ASYNC,
};
- data = kmalloc(sizeof(*data), GFP_KERNEL);
+ data = kzalloc(sizeof(*data), GFP_KERNEL);
if (data == NULL)
return ERR_PTR(-ENOMEM);
task_setup_data.callback_data = data,
diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 874972d..4d6d35d 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -55,7 +55,6 @@ struct nfs_write_data *nfs_commitdata_alloc(void)
if (p) {
memset(p, 0, sizeof(*p));
INIT_LIST_HEAD(&p->pages);
- p->res.seq_res.sr_slotid = NFS4_MAX_SLOT_TABLE;
}
return p;
}
@@ -75,7 +74,6 @@ struct nfs_write_data *nfs_writedata_alloc(unsigned int pagecount)
memset(p, 0, sizeof(*p));
INIT_LIST_HEAD(&p->pages);
p->npages = pagecount;
- p->res.seq_res.sr_slotid = NFS4_MAX_SLOT_TABLE;
if (pagecount <= ARRAY_SIZE(p->page_array))
p->pagevec = p->page_array;
else {
diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index 172df83..5772b2c 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -170,7 +170,7 @@ struct nfs4_sequence_args {
struct nfs4_sequence_res {
struct nfs4_session *sr_session;
- u8 sr_slotid; /* slot used to send request */
+ struct nfs4_slot *sr_slot; /* slot used to send request */
int sr_status; /* sequence operation status */
unsigned long sr_renewal_time;
u32 sr_status_flags;
--
1.7.2.3
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