2018-08-13 22:15:48

by Olga Kornievskaia

Subject: [PATCH 09/11] NFS recover from destination server reboot for copies

Mark the destination state to indicate a server-side copy is
happening. On detecting a reboot and recovering open state check
if any state is engaged in a server-side copy, if so, find the
copy and mark it and then signal the waiting thread. Upon wakeup,
if copy was marked then propage EAGAIN to the nfsd_copy_file_range
and restart the copy from scratch.

Signed-off-by: Olga Kornievskaia <[email protected]>
---
fs/nfs/nfs42proc.c | 16 +++++++++++++---
fs/nfs/nfs4_fs.h | 3 +++
fs/nfs/nfs4file.c | 9 +++++++--
fs/nfs/nfs4state.c | 16 ++++++++++++++++
include/linux/nfs_fs.h | 2 ++
5 files changed, 41 insertions(+), 5 deletions(-)

diff --git a/fs/nfs/nfs42proc.c b/fs/nfs/nfs42proc.c
index aeb9837..0c16b91 100644
--- a/fs/nfs/nfs42proc.c
+++ b/fs/nfs/nfs42proc.c
@@ -140,6 +140,7 @@ static int handle_async_copy(struct nfs42_copy_res *res,
struct nfs4_copy_state *copy;
int status = NFS4_OK;
bool found_pending = false;
+ struct nfs_open_context *ctx = nfs_file_open_context(dst);

spin_lock(&server->nfs_client->cl_lock);
list_for_each_entry(copy, &server->nfs_client->pending_cb_stateids,
@@ -163,6 +164,7 @@ static int handle_async_copy(struct nfs42_copy_res *res,
}
memcpy(&copy->stateid, &res->write_res.stateid, NFS4_STATEID_SIZE);
init_completion(&copy->completion);
+ copy->parent_state = ctx->state;

list_add_tail(&copy->copies, &server->ss_copies);
spin_unlock(&server->nfs_client->cl_lock);
@@ -172,9 +174,10 @@ static int handle_async_copy(struct nfs42_copy_res *res,
list_del_init(&copy->copies);
spin_unlock(&server->nfs_client->cl_lock);
if (status == -ERESTARTSYS) {
- nfs42_do_offload_cancel_async(dst, &copy->stateid);
- kfree(copy);
- return status;
+ goto out_cancel;
+ } else if (copy->flags) {
+ status = -EAGAIN;
+ goto out_cancel;
}
out:
res->write_res.count = copy->count;
@@ -183,6 +186,10 @@ static int handle_async_copy(struct nfs42_copy_res *res,

kfree(copy);
return status;
+out_cancel:
+ nfs42_do_offload_cancel_async(dst, &copy->stateid);
+ kfree(copy);
+ return status;
}

static ssize_t _nfs42_proc_copy(struct file *src,
@@ -230,6 +237,9 @@ static ssize_t _nfs42_proc_copy(struct file *src,
if (!res->commit_res.verf)
return -ENOMEM;
}
+ set_bit(NFS_CLNT_DST_SSC_COPY_STATE,
+ &dst_lock->open_context->state->flags);
+
status = nfs4_call_sync(server->client, server, &msg,
&args->seq_args, &res->seq_res, 0);
if (status == -ENOTSUPP)
diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h
index a417aaa..345197c 100644
--- a/fs/nfs/nfs4_fs.h
+++ b/fs/nfs/nfs4_fs.h
@@ -163,6 +163,9 @@ enum {
NFS_STATE_RECOVERY_FAILED, /* OPEN stateid state recovery failed */
NFS_STATE_MAY_NOTIFY_LOCK, /* server may CB_NOTIFY_LOCK */
NFS_STATE_CHANGE_WAIT, /* A state changing operation is outstanding */
+#ifdef CONFIG_NFS_V4_2
+ NFS_CLNT_DST_SSC_COPY_STATE, /* dst server open state on client*/
+#endif /* CONFIG_NFS_V4_2 */
};

struct nfs4_state {
diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c
index 6b3b372..eaef5fa 100644
--- a/fs/nfs/nfs4file.c
+++ b/fs/nfs/nfs4file.c
@@ -133,10 +133,15 @@ static ssize_t nfs4_copy_file_range(struct file *file_in, loff_t pos_in,
struct file *file_out, loff_t pos_out,
size_t count, unsigned int flags)
{
+ ssize_t ret;
+
if (file_inode(file_in) == file_inode(file_out))
return -EINVAL;
-
- return nfs42_proc_copy(file_in, pos_in, file_out, pos_out, count);
+retry:
+ ret = nfs42_proc_copy(file_in, pos_in, file_out, pos_out, count);
+ if (ret == -EAGAIN)
+ goto retry;
+ return ret;
}

static loff_t nfs4_file_llseek(struct file *filep, loff_t offset, int whence)
diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c
index 2bf2eaa..12cb450 100644
--- a/fs/nfs/nfs4state.c
+++ b/fs/nfs/nfs4state.c
@@ -1588,6 +1588,22 @@ static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs
}
clear_bit(NFS_STATE_RECLAIM_NOGRACE,
&state->flags);
+#ifdef CONFIG_NFS_V4_2
+ if (test_bit(NFS_CLNT_DST_SSC_COPY_STATE, &state->flags)) {
+ struct nfs4_copy_state *copy;
+
+ spin_lock(&sp->so_server->nfs_client->cl_lock);
+ list_for_each_entry(copy, &sp->so_server->ss_copies, copies) {
+ if (memcmp(&state->stateid.other, &copy->parent_state->stateid.other, NFS4_STATEID_SIZE))
+ continue;
+ copy->flags = 1;
+ complete(&copy->completion);
+ printk("AGLO: server rebooted waking up the copy\n");
+ break;
+ }
+ spin_unlock(&sp->so_server->nfs_client->cl_lock);
+ }
+#endif /* CONFIG_NFS_V4_2 */
nfs4_put_open_state(state);
spin_lock(&sp->so_lock);
goto restart;
diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h
index 645ad8e..a0831e9 100644
--- a/include/linux/nfs_fs.h
+++ b/include/linux/nfs_fs.h
@@ -192,6 +192,8 @@ struct nfs4_copy_state {
uint64_t count;
struct nfs_writeverf verf;
int error;
+ int flags;
+ struct nfs4_state *parent_state;
};

/*
--
1.8.3.1