ceph: re-send AIO write request when getting -EOLDSNAP error

When receiving -EOLDSNAP from OSD, we need to re-send corresponding
write request. Due to locking issue, we can send new request inside
another OSD request's complete callback. So we use worker to re-send
request for AIO write.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
This commit is contained in:
Yan, Zheng 2015-12-24 08:44:20 +08:00 committed by Ilya Dryomov
parent c8fe9b17d0
commit 5be0389dac

View File

@ -554,9 +554,17 @@ struct ceph_aio_request {
struct list_head osd_reqs;
unsigned num_reqs;
atomic_t pending_reqs;
struct timespec mtime;
struct ceph_cap_flush *prealloc_cf;
};
struct ceph_aio_work {
struct work_struct work;
struct ceph_osd_request *req;
};
static void ceph_aio_retry_work(struct work_struct *work);
static void ceph_aio_complete(struct inode *inode,
struct ceph_aio_request *aio_req)
{
@ -614,10 +622,19 @@ static void ceph_aio_complete_req(struct ceph_osd_request *req,
inode, rc, osd_data->length);
if (rc == -EOLDSNAPC) {
BUG_ON(1);
}
struct ceph_aio_work *aio_work;
BUG_ON(!aio_req->write);
if (!aio_req->write) {
aio_work = kmalloc(sizeof(*aio_work), GFP_NOFS);
if (aio_work) {
INIT_WORK(&aio_work->work, ceph_aio_retry_work);
aio_work->req = req;
queue_work(ceph_inode_to_client(inode)->wb_wq,
&aio_work->work);
return;
}
rc = -ENOMEM;
} else if (!aio_req->write) {
if (rc == -ENOENT)
rc = 0;
if (rc >= 0 && osd_data->length > rc) {
@ -653,6 +670,69 @@ static void ceph_aio_complete_req(struct ceph_osd_request *req,
return;
}
static void ceph_aio_retry_work(struct work_struct *work)
{
struct ceph_aio_work *aio_work =
container_of(work, struct ceph_aio_work, work);
struct ceph_osd_request *orig_req = aio_work->req;
struct ceph_aio_request *aio_req = orig_req->r_priv;
struct inode *inode = orig_req->r_inode;
struct ceph_inode_info *ci = ceph_inode(inode);
struct ceph_snap_context *snapc;
struct ceph_osd_request *req;
int ret;
spin_lock(&ci->i_ceph_lock);
if (__ceph_have_pending_cap_snap(ci)) {
struct ceph_cap_snap *capsnap =
list_last_entry(&ci->i_cap_snaps,
struct ceph_cap_snap,
ci_item);
snapc = ceph_get_snap_context(capsnap->context);
} else {
BUG_ON(!ci->i_head_snapc);
snapc = ceph_get_snap_context(ci->i_head_snapc);
}
spin_unlock(&ci->i_ceph_lock);
req = ceph_osdc_alloc_request(orig_req->r_osdc, snapc, 2,
false, GFP_NOFS);
if (IS_ERR(req)) {
ret = PTR_ERR(req);
req = orig_req;
goto out;
}
req->r_flags = CEPH_OSD_FLAG_ORDERSNAP |
CEPH_OSD_FLAG_ONDISK |
CEPH_OSD_FLAG_WRITE;
req->r_base_oloc = orig_req->r_base_oloc;
req->r_base_oid = orig_req->r_base_oid;
req->r_ops[0] = orig_req->r_ops[0];
osd_req_op_init(req, 1, CEPH_OSD_OP_STARTSYNC, 0);
ceph_osdc_build_request(req, req->r_ops[0].extent.offset,
snapc, CEPH_NOSNAP, &aio_req->mtime);
ceph_put_snap_context(snapc);
ceph_osdc_put_request(orig_req);
req->r_callback = ceph_aio_complete_req;
req->r_inode = inode;
req->r_priv = aio_req;
ret = ceph_osdc_start_request(req->r_osdc, req, false);
out:
if (ret < 0) {
BUG_ON(ret == -EOLDSNAPC);
req->r_result = ret;
ceph_aio_complete_req(req, NULL);
}
kfree(aio_work);
}
/*
* Write commit request unsafe callback, called to tell us when a
* request is unsafe (that is, in flight--has been handed to the
@ -772,6 +852,7 @@ ceph_direct_read_write(struct kiocb *iocb, struct iov_iter *iter,
aio_req->write = write;
INIT_LIST_HEAD(&aio_req->osd_reqs);
if (write) {
aio_req->mtime = mtime;
swap(aio_req->prealloc_cf, *pcf);
}
}
@ -867,6 +948,7 @@ ceph_direct_read_write(struct kiocb *iocb, struct iov_iter *iter,
ret = ceph_osdc_start_request(req->r_osdc,
req, false);
if (ret < 0) {
BUG_ON(ret == -EOLDSNAPC);
req->r_result = ret;
ceph_aio_complete_req(req, NULL);
}