/*
 * Copyright (c) 2016 Tom Haynes <loghyr@primarydata.com>
 *
 * The following implements a super-simple flex-file server
 * where the NFSv4.1 mds is also the ds. And the storage is
 * the same. I.e., writing to the mds via a NFSv4.1 WRITE
 * goes to the same location as the NFSv3 WRITE.
 */
#include <linux/slab.h>

#include <linux/nfsd/debug.h>

#include <linux/sunrpc/addr.h>

#include "flexfilelayoutxdr.h"
#include "pnfs.h"

#define NFSDDBG_FACILITY	NFSDDBG_PNFS

static __be32
nfsd4_ff_proc_layoutget(struct inode *inode, const struct svc_fh *fhp,
		struct nfsd4_layoutget *args)
{
	struct nfsd4_layout_seg *seg = &args->lg_seg;
	u32 device_generation = 0;
	int error;
	uid_t u;

	struct pnfs_ff_layout *fl;

	/*
	 * The super simple flex file server has 1 mirror, 1 data server,
	 * and 1 file handle. So instead of 4 allocs, do 1 for now.
	 * Zero it out for the stateid - don't want junk in there!
	 */
	error = -ENOMEM;
	fl = kzalloc(sizeof(*fl), GFP_KERNEL);
	if (!fl)
		goto out_error;
	args->lg_content = fl;

	/*
	 * Avoid layout commit, try to force the I/O to the DS,
	 * and for fun, cause all IOMODE_RW layout segments to
	 * effectively be WRITE only.
	 */
	fl->flags = FF_FLAGS_NO_LAYOUTCOMMIT | FF_FLAGS_NO_IO_THRU_MDS |
		    FF_FLAGS_NO_READ_IO;

	/* Do not allow a IOMODE_READ segment to have write pemissions */
	if (seg->iomode == IOMODE_READ) {
		u = from_kuid(&init_user_ns, inode->i_uid) + 1;
		fl->uid = make_kuid(&init_user_ns, u);
	} else
		fl->uid = inode->i_uid;
	fl->gid = inode->i_gid;

	error = nfsd4_set_deviceid(&fl->deviceid, fhp, device_generation);
	if (error)
		goto out_error;

	fl->fh.size = fhp->fh_handle.fh_size;
	memcpy(fl->fh.data, &fhp->fh_handle.fh_base, fl->fh.size);

	/* Give whole file layout segments */
	seg->offset = 0;
	seg->length = NFS4_MAX_UINT64;

	dprintk("GET: 0x%llx:0x%llx %d\n", seg->offset, seg->length,
		seg->iomode);
	return 0;

out_error:
	seg->length = 0;
	return nfserrno(error);
}

static __be32
nfsd4_ff_proc_getdeviceinfo(struct super_block *sb, struct svc_rqst *rqstp,
		struct nfs4_client *clp, struct nfsd4_getdeviceinfo *gdp)
{
	struct pnfs_ff_device_addr *da;

	u16 port;
	char addr[INET6_ADDRSTRLEN];

	da = kzalloc(sizeof(struct pnfs_ff_device_addr), GFP_KERNEL);
	if (!da)
		return nfserrno(-ENOMEM);

	gdp->gd_device = da;

	da->version = 3;
	da->minor_version = 0;

	da->rsize = svc_max_payload(rqstp);
	da->wsize = da->rsize;

	rpc_ntop((struct sockaddr *)&rqstp->rq_daddr,
		 addr, INET6_ADDRSTRLEN);
	if (rqstp->rq_daddr.ss_family == AF_INET) {
		struct sockaddr_in *sin;

		sin = (struct sockaddr_in *)&rqstp->rq_daddr;
		port = ntohs(sin->sin_port);
		snprintf(da->netaddr.netid, FF_NETID_LEN + 1, "tcp");
		da->netaddr.netid_len = 3;
	} else {
		struct sockaddr_in6 *sin6;

		sin6 = (struct sockaddr_in6 *)&rqstp->rq_daddr;
		port = ntohs(sin6->sin6_port);
		snprintf(da->netaddr.netid, FF_NETID_LEN + 1, "tcp6");
		da->netaddr.netid_len = 4;
	}

	da->netaddr.addr_len =
		snprintf(da->netaddr.addr, FF_ADDR_LEN + 1,
			 "%s.%hhu.%hhu", addr, port >> 8, port & 0xff);

	da->tightly_coupled = false;

	return 0;
}

const struct nfsd4_layout_ops ff_layout_ops = {
	.notify_types		=
			NOTIFY_DEVICEID4_DELETE | NOTIFY_DEVICEID4_CHANGE,
	.disable_recalls	= true,
	.proc_getdeviceinfo	= nfsd4_ff_proc_getdeviceinfo,
	.encode_getdeviceinfo	= nfsd4_ff_encode_getdeviceinfo,
	.proc_layoutget		= nfsd4_ff_proc_layoutget,
	.encode_layoutget	= nfsd4_ff_encode_layoutget,
};
r</th><th class='left'>Files</th><th class='left'>Lines</th></tr>
s-private-remove'/><input type='hidden' name='id' value='433e19cf33d34bb6751c874a9c00980552fe508c'/><table><tr><td colspan='2'/></tr><tr><td class='label'>context:</td><td class='ctrl'><select name='context' onchange='this.form.submit();'><option value='1'>1</option><option value='2'>2</option><option value='3' selected='selected'>3</option><option value='4'>4</option><option value='5'>5</option><option value='6'>6</option><option value='7'>7</option><option value='8'>8</option><option value='9'>9</option><option value='10'>10</option><option value='15'>15</option><option value='20'>20</option><option value='25'>25</option><option value='30'>30</option><option value='35'>35</option><option value='40'>40</option></select></td></tr><tr><td class='label'>space:</td><td class='ctrl'><select name='ignorews' onchange='this.form.submit();'><option value='0' selected='selected'>include</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>Dexuan Cui &lt;decui@microsoft.com&gt;</td><td class='right'>2017-01-28 11:46:02 -0700</td></tr>
<tr><th>committer</th><td>Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;</td><td class='right'>2017-01-31 10:59:48 +0100</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/net/x25/x25_subr.c?h=nds-private-remove&amp;id=433e19cf33d34bb6751c874a9c00980552fe508c'>433e19cf33d34bb6751c874a9c00980552fe508c</a> (<a href='/cgit.cgi/linux/net-next.git/patch/net/x25/x25_subr.c?id=433e19cf33d34bb6751c874a9c00980552fe508c'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?h=nds-private-remove&amp;id=433e19cf33d34bb6751c874a9c00980552fe508c'>ce6547ef2987fbb289fa28f03536328a42781651</a> /<a href='/cgit.cgi/linux/net-next.git/tree/net/x25/x25_subr.c?h=nds-private-remove&amp;id=433e19cf33d34bb6751c874a9c00980552fe508c'>net/x25/x25_subr.c</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/net/x25/x25_subr.c?h=nds-private-remove&amp;id=191e885a2e130e639bb0c8ee350d7047294f2ce6'>191e885a2e130e639bb0c8ee350d7047294f2ce6</a> (<a href='/cgit.cgi/linux/net-next.git/diff/net/x25/x25_subr.c?h=nds-private-remove&amp;id=433e19cf33d34bb6751c874a9c00980552fe508c&amp;id2=191e885a2e130e639bb0c8ee350d7047294f2ce6'>diff</a>)</td></tr></table>
<div class='commit-subject'>Drivers: hv: vmbus: finally fix hv_need_to_signal_on_read()</div><div class='commit-msg'>Commit a389fcfd2cb5 ("Drivers: hv: vmbus: Fix signaling logic in
hv_need_to_signal_on_read()")
added the proper mb(), but removed the test "prev_write_sz &lt; pending_sz"
when making the signal decision.

As a result, the guest can signal the host unnecessarily,
and then the host can throttle the guest because the host
thinks the guest is buggy or malicious; finally the user
running stress test can perceive intermittent freeze of
the guest.

This patch brings back the test, and properly handles the
in-place consumption APIs used by NetVSC (see get_next_pkt_raw(),
put_pkt_raw() and commit_rd_index()).

Fixes: a389fcfd2cb5 ("Drivers: hv: vmbus: Fix signaling logic in
hv_need_to_signal_on_read()")

Signed-off-by: Dexuan Cui &lt;decui@microsoft.com&gt;
Reported-by: Rolf Neugebauer &lt;rolf.neugebauer@docker.com&gt;
Tested-by: Rolf Neugebauer &lt;rolf.neugebauer@docker.com&gt;
Cc: "K. Y. Srinivasan" &lt;kys@microsoft.com&gt;
Cc: Haiyang Zhang &lt;haiyangz@microsoft.com&gt;
Cc: Stephen Hemminger &lt;sthemmin@microsoft.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: K. Y. Srinivasan &lt;kys@microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?h=nds-private-remove&amp;id=433e19cf33d34bb6751c874a9c00980552fe508c'>Diffstat</a> (limited to 'net/x25/x25_subr.c')</div><table summary='diffstat' class='diffstat'>