BMC/Intel-BMC/linux.git/net/9p/trans_virtio.c, branch dev

9p/trans_virtio: reset virtio device on remove

2015-07-13T16:47:10+00:00

On device shutdown/removal, virtio drivers need to trigger a reset on the device; if this is neglected, the virtio core will complain about non-zero device status. This patch resets the status when the 9p virtio driver is removed from the system by calling vdev->config->reset on the virtio_device to send a reset to the host virtio device. Signed-off-by: Pierre Morel Reviewed-by: Cornelia Huck Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin

Merge tag 'for-linus-4.1-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs

2015-04-18T21:45:30+00:00

Pull 9pfs updates from Eric Van Hensbergen: "Some accumulated cleanup patches for kerneldoc and unused variables as well as some lock bug fixes and adding privateport option for RDMA" * tag 'for-linus-4.1-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs: net/9p: add a privport option for RDMA transport. fs/9p: Initialize status in v9fs_file_do_lock. net/9p: Initialize opts->privport as it should be. net/9p: use memcpy() instead of snprintf() in p9_mount_tag_show() 9p: use unsigned integers for nwqid/count 9p: do not crash on unknown lock status code 9p: fix error handling in v9fs_file_do_lock 9p: remove unused variable in p9_fd_create() 9p: kerneldoc warning fixes

net/9p: switch the guts of p9_client_{read,write}() to iov_iter

2015-04-12T02:28:25+00:00

... and have get_user_pages_fast() mapping fewer pages than requested to generate a short read/write. Signed-off-by: Al Viro

net/9p: use memcpy() instead of snprintf() in p9_mount_tag_show()

2015-03-20T14:34:43+00:00

p9_mount_tag_show() uses '%s' format string to print non-NULL terminated chan->tag string. This leads to out of bounds memory read, because format '%s' implies that string is NULL-terminated. The length of string is know here, so its simpler and safer to use memcpy instead of snprintf(). Signed-off-by: Andrey Ryabinin Signed-off-by: Dominique Martinet Signed-off-by: Eric Van Hensbergen

9p/trans_virtio: fix hot-unplug

2015-03-13T05:25:41+00:00

On device hot-unplug, 9p/virtio currently will kfree channel while it might still be in use. Of course, it might stay used forever, so it's an extremely ugly hack, but it seems better than use-after-free that we have now. [ Unused variable removed, whitespace cleanup, msg single-lined --RR ] Signed-off-by: Michael S. Tsirkin Signed-off-by: Rusty Russell

virtio/9p: verify device has config space

2015-01-21T05:58:45+00:00

Some devices might not implement config space access (e.g. remoteproc used not to - before 3.9). virtio/9p needs config space access so make it fail gracefully if not there. Signed-off-by: Michael S. Tsirkin Signed-off-by: Rusty Russell

9p/trans_virtio: enable VQs early

2014-10-14T23:55:04+00:00

virtio spec requires drivers to set DRIVER_OK before using VQs. This is set automatically after probe returns, but virtio 9p device adds self to channel list within probe, at which point VQ can be used in violation of the spec. To fix, call virtio_device_ready before using VQs. Signed-off-by: Michael S. Tsirkin Signed-off-by: Rusty Russell

Merge tag 'for-linus-3.15' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs

2014-04-11T21:14:57+00:00

Pull 9p changes from Eric Van Hensbergen: "A bunch of updates and cleanup within the transport layer, particularly with a focus on RDMA" * tag 'for-linus-3.15' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs: 9pnet_rdma: check token type before int conversion 9pnet: trans_fd : allocate struct p9_trans_fd and struct p9_conn together. 9pnet: p9_client->conn field is unused. Remove it. 9P: Get rid of REQ_STATUS_FLSH 9pnet_rdma: add cancelled() 9pnet_rdma: update request status during send 9P: Add cancelled() to the transport functions. net: Mark function as static in 9p/client.c 9P: Add memory barriers to protect request fields over cb/rpc threads handoff

9P: Add memory barriers to protect request fields over cb/rpc threads handoff

2014-03-25T21:37:59+00:00

We need barriers to guarantee this pattern works as intended: [w] req->rc, 1 [r] req->status, 1 wmb rmb [w] req->status, 1 [r] req->rc Where the wmb ensures that rc gets written before status, and the rmb ensures that if you observe status == 1, rc is the new value. Signed-off-by: Dominique Martinet Signed-off-by: Eric Van Hensbergen

9p/trans_virtio.c: Fix broken zero-copy on vmalloc() buffers

2014-02-11T01:48:54+00:00

The 9p-virtio transport does zero copy on things larger than 1024 bytes in size. It accomplishes this by returning the physical addresses of pages to the virtio-pci device. At present, the translation is usually a bit shift. That approach produces an invalid page address when we read/write to vmalloc buffers, such as those used for Linux kernel modules. Any attempt to load a Linux kernel module from 9p-virtio produces the following stack. [] p9_virtio_zc_request+0x45e/0x510 [] p9_client_zc_rpc.constprop.16+0xfd/0x4f0 [] p9_client_read+0x15d/0x240 [] v9fs_fid_readn+0x50/0xa0 [] v9fs_file_readn+0x10/0x20 [] v9fs_file_read+0x37/0x70 [] vfs_read+0x9b/0x160 [] kernel_read+0x41/0x60 [] copy_module_from_fd.isra.34+0xfb/0x180 Subsequently, QEMU will die printing: qemu-system-x86_64: virtio: trying to map MMIO memory This patch enables 9p-virtio to correctly handle this case. This not only enables us to load Linux kernel modules off virtfs, but also enables ZFS file-based vdevs on virtfs to be used without killing QEMU. Special thanks to both Avi Kivity and Alexander Graf for their interpretation of QEMU backtraces. Without their guidence, tracking down this bug would have taken much longer. Also, special thanks to Linus Torvalds for his insightful explanation of why this should use is_vmalloc_addr() instead of is_vmalloc_or_module_addr(): https://lkml.org/lkml/2014/2/8/272 Signed-off-by: Richard Yao Signed-off-by: David S. Miller