diff options
author | David Howells <dhowells@redhat.com> | 2021-07-09 10:41:17 +0300 |
---|---|---|
committer | David Howells <dhowells@redhat.com> | 2023-12-28 12:42:44 +0300 |
commit | 21d706d5cf570917594b21edee81893bdce09ab8 (patch) | |
tree | a692b502c516bfafba77a2d98088155fe314ea0c /fs/netfs | |
parent | 92b6cc5d1e7cbe569f00e9c1249ac8214fd5e2d2 (diff) | |
download | linux-21d706d5cf570917594b21edee81893bdce09ab8.tar.xz |
netfs: Add support for DIO buffering
Add a bvec array pointer and an iterator to netfs_io_request for either
holding a copy of a DIO iterator or a list of all the bits of buffer
pointed to by a DIO iterator.
There are two problems: Firstly, if an iovec-class iov_iter is passed to
->read_iter() or ->write_iter(), this cannot be passed directly to
kernel_sendmsg() or kernel_recvmsg() as that may cause locking recursion if
a fault is generated, so we need to keep track of the pages involved
separately.
Secondly, if the I/O is asynchronous, we must copy the iov_iter describing
the buffer before returning to the caller as it may be immediately
deallocated.
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
cc: linux-fsdevel@vger.kernel.org
cc: linux-mm@kvack.org
Diffstat (limited to 'fs/netfs')
-rw-r--r-- | fs/netfs/objects.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/fs/netfs/objects.c b/fs/netfs/objects.c index 1bd20bdad983..4df5e5eeada6 100644 --- a/fs/netfs/objects.c +++ b/fs/netfs/objects.c @@ -76,6 +76,7 @@ static void netfs_free_request(struct work_struct *work) { struct netfs_io_request *rreq = container_of(work, struct netfs_io_request, work); + unsigned int i; trace_netfs_rreq(rreq, netfs_rreq_trace_free); netfs_proc_del_rreq(rreq); @@ -84,6 +85,15 @@ static void netfs_free_request(struct work_struct *work) rreq->netfs_ops->free_request(rreq); if (rreq->cache_resources.ops) rreq->cache_resources.ops->end_operation(&rreq->cache_resources); + if (rreq->direct_bv) { + for (i = 0; i < rreq->direct_bv_count; i++) { + if (rreq->direct_bv[i].bv_page) { + if (rreq->direct_bv_unpin) + unpin_user_page(rreq->direct_bv[i].bv_page); + } + } + kvfree(rreq->direct_bv); + } kfree_rcu(rreq, rcu); netfs_stat_d(&netfs_n_rh_rreq); } |