From: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
In order to avoid issues with stack overflow, just call the read
routines from a workqueue job.
Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx>
---
fs/nfs/localio.c | 39 +++++++++++++++++++++++++++++----------
1 file changed, 29 insertions(+), 10 deletions(-)
diff --git a/fs/nfs/localio.c b/fs/nfs/localio.c
index 2c6811b20dcf..d997f0a96627 100644
--- a/fs/nfs/localio.c
+++ b/fs/nfs/localio.c
@@ -465,21 +465,38 @@ nfs_local_read_aio_complete(struct kiocb *kiocb, long ret)
nfs_local_pgio_complete(iocb);
}
-static int
-nfs_do_local_read(struct nfs_pgio_header *hdr, struct file *filp,
- const struct rpc_call_ops *call_ops)
+static void nfs_local_call_read(struct work_struct *work)
{
- struct nfs_local_kiocb *iocb;
+ struct nfs_local_io_args *args =
+ container_of(work, struct nfs_local_io_args, work);
+ struct nfs_local_kiocb *iocb = args->iocb;
+ struct file *filp = iocb->kiocb.ki_filp;
struct iov_iter iter;
ssize_t status;
+ nfs_local_iter_init(&iter, iocb, READ);
+
+ status = filp->f_op->read_iter(&iocb->kiocb, &iter);
+ if (status != -EIOCBQUEUED) {
+ nfs_local_read_done(iocb, status);
+ nfs_local_pgio_release(iocb);
+ }
+ complete(args->done);
+}
+
+static int nfs_do_local_read(struct nfs_pgio_header *hdr, struct file *filp,
+ const struct rpc_call_ops *call_ops)
+{
+ struct nfs_local_io_args args;
+ DECLARE_COMPLETION_ONSTACK(done);
+ struct nfs_local_kiocb *iocb;
+
dprintk("%s: vfs_read count=%u pos=%llu\n",
__func__, hdr->args.count, hdr->args.offset);
iocb = nfs_local_iocb_alloc(hdr, filp, GFP_KERNEL);
if (iocb == NULL)
return -ENOMEM;
- nfs_local_iter_init(&iter, iocb, READ);
nfs_local_pgio_init(hdr, call_ops);
hdr->res.eof = false;
@@ -489,11 +506,13 @@ nfs_do_local_read(struct nfs_pgio_header *hdr, struct file *filp,
iocb->kiocb.ki_complete = nfs_local_read_aio_complete;
}
- status = filp->f_op->read_iter(&iocb->kiocb, &iter);
- if (status != -EIOCBQUEUED) {
- nfs_local_read_done(iocb, status);
- nfs_local_pgio_release(iocb);
- }
+ args.iocb = iocb;
+ args.done = &done;
+ INIT_WORK_ONSTACK(&args.work, nfs_local_call_read);
+
+ queue_work(nfsiod_workqueue, &args.work);
+ wait_for_completion(&done);
+ destroy_work_on_stack(&args.work);
return 0;
}
--
2.44.0
