summaryrefslogtreecommitdiffstats
path: root/kernel/drivers/scsi/scsi_netlink.c
blob: 109802f776ed71cea6857eda9ae6ccc3e0b41f80 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
/*
 *  scsi_netlink.c  - SCSI Transport Netlink Interface
 *
 *  Copyright (C) 2006   James Smart, Emulex Corporation
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */
#include <linux/time.h>
#include <linux/jiffies.h>
#include <linux/security.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/export.h>
#include <net/sock.h>
#include <net/netlink.h>

#include <scsi/scsi_netlink.h>
#include "scsi_priv.h"

struct sock *scsi_nl_sock = NULL;
EXPORT_SYMBOL_GPL(scsi_nl_sock);

/**
 * scsi_nl_rcv_msg - Receive message handler.
 * @skb:		socket receive buffer
 *
 * Description: Extracts message from a receive buffer.
 *    Validates message header and calls appropriate transport message handler
 *
 *
 **/
static void
scsi_nl_rcv_msg(struct sk_buff *skb)
{
	struct nlmsghdr *nlh;
	struct scsi_nl_hdr *hdr;
	u32 rlen;
	int err, tport;

	while (skb->len >= NLMSG_HDRLEN) {
		err = 0;

		nlh = nlmsg_hdr(skb);
		if ((nlh->nlmsg_len < (sizeof(*nlh) + sizeof(*hdr))) ||
		    (skb->len < nlh->nlmsg_len)) {
			printk(KERN_WARNING "%s: discarding partial skb\n",
				 __func__);
			return;
		}

		rlen = NLMSG_ALIGN(nlh->nlmsg_len);
		if (rlen > skb->len)
			rlen = skb->len;

		if (nlh->nlmsg_type != SCSI_TRANSPORT_MSG) {
			err = -EBADMSG;
			goto next_msg;
		}

		hdr = nlmsg_data(nlh
/**************************************************************************
 *
 * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
 * All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sub license, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice (including the
 * next paragraph) shall be included in all copies or substantial portions
 * of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
 * USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 **************************************************************************/
/*
 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
 */

#define pr_fmt(fmt) "[TTM] " fmt

#include <ttm/ttm_module.h>
#include <ttm/ttm_bo_driver.h>
#include <ttm/ttm_placement.h>
#include <drm/drm_vma_manager.h>
#include <linux/mm.h>
#include <linux/rbtree.h>
#include <linux/module.h>
#include <linux/uaccess.h>

#define TTM_BO_VM_NUM_PREFAULT 16

static int ttm_bo_vm_fault_idle(struct ttm_buffer_object *bo,
				struct vm_area_struct *vma,
				struct vm_fault *vmf)
{
	int ret = 0;

	if (likely(!test_bit(TTM_BO_PRIV_FLAG_MOVING, &bo->priv_flags)))
		goto out_unlock;

	/*
	 * Quick non-stalling check for idle.
	 */
	ret = ttm_bo_wait(bo, false, false, true);
	if (likely(ret == 0))
		goto out_unlock;

	/*
	 * If possible, avoid waiting for GPU with mmap_sem
	 * held.
	 */
	if (vmf->flags & FAULT_FLAG_ALLOW_RETRY) {
		ret = VM_FAULT_RETRY;
		if (vmf->flags & FAULT_FLAG_RETRY_NOWAIT)
			goto out_unlock;

		up_read(&vma->vm_mm->mmap_sem);
		(void) ttm_bo_wait(bo, false, true, false);
		goto out_unlock;
	}

	/*
	 * Ordinary wait.
	 */
	ret = ttm_bo_wait(bo, false, true, false);
	if (unlikely(ret != 0))
		ret = (ret != -ERESTARTSYS) ? VM_FAULT_SIGBUS :
			VM_FAULT_NOPAGE
="n">bdev; unsigned long page_offset; unsigned long page_last; unsigned long pfn; struct ttm_tt *ttm = NULL; struct page *page; int ret; int i; unsigned long address = (unsigned long)vmf->virtual_address; int retval = VM_FAULT_NOPAGE; struct ttm_mem_type_manager *man = &bdev->man[bo->mem.mem_type]; struct vm_area_struct cvma; /* * Work around locking order reversal in fault / nopfn * between mmap_sem and bo_reserve: Perform a trylock operation * for reserve, and if it fails, retry the fault after waiting * for the buffer to become unreserved. */ ret = ttm_bo_reserve(bo, true, true, false, NULL); if (unlikely(ret != 0)) { if (ret != -EBUSY) return VM_FAULT_NOPAGE; if (vmf->flags & FAULT_FLAG_ALLOW_RETRY) { if (!(vmf->flags & FAULT_FLAG_RETRY_NOWAIT)) { up_read(&vma->vm_mm->mmap_sem); (void) ttm_bo_wait_unreserved(bo); } return VM_FAULT_RETRY; } /* * If we'd want to change locking order to * mmap_sem -> bo::reserve, we'd use a blocking reserve here * instead of retrying the fault... */ return VM_FAULT_NOPAGE; } /* * Refuse to fault imported pages. This should be handled * (if at all) by redirecting mmap to the exporter. */ if (bo->ttm && (bo->ttm->page_flags & TTM_PAGE_FLAG_SG)) { retval = VM_FAULT_SIGBUS; goto out_unlock; } if (bdev->driver->fault_reserve_notify) { ret = bdev->driver->fault_reserve_notify(bo); switch (ret) { case 0: break; case -EBUSY: case -ERESTARTSYS: retval = VM_FAULT_NOPAGE; goto out_unlock; default: retval = VM_FAULT_SIGBUS; goto out_unlock; } } /* * Wait for buffer data in transit, due to a pipelined * move. */ ret = ttm_bo_vm_fault_idle(bo, vma, vmf); if (unlikely(ret != 0)) { retval = ret; goto out_unlock; } ret = ttm_mem_io_lock(man, true); if (unlikely(ret != 0)) { retval = VM_FAULT_NOPAGE; goto out_unlock; } ret = ttm_mem_io_reserve_vm(bo); if (unlikely(ret != 0)) { retval = VM_FAULT_SIGBUS; goto out_io_unlock; } page_offset = ((address - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff - drm_vma_node_start(&bo->vma_node); page_last = vma_pages(vma) + vma->vm_pgoff - drm_vma_node_start(&bo->vma_node); if (unlikely(page_offset >= bo->num_pages)) { retval = VM_FAULT_SIGBUS; goto out_io_unlock; } /* * Make a local vma copy to modify the page_prot member * and vm_flags if necessary. The vma parameter is protected * by mmap_sem in write mode. */ cvma = *vma; cvma.vm_page_prot = vm_get_page_prot(cvma.vm_flags); if (bo->mem.bus.is_iomem) { cvma.vm_page_prot = ttm_io_prot(bo->mem.placement, cvma.vm_page_prot); } else { ttm = bo->ttm; cvma.vm_page_prot = ttm_io_prot(bo->mem.placement, cvma.vm_page_prot); /* Allocate all page at once, most common usage */ if (ttm->bdev->driver->ttm_tt_populate(ttm)) { retval = VM_FAULT_OOM; goto out_io_unlock; } } /* * Speculatively prefault a number of pages. Only error on * first page. */ for (i = 0; i < TTM_BO_VM_NUM_PREFAULT; ++i) { if (bo->mem.bus.is_iomem) pfn = ((bo->mem.bus.base + bo->mem.bus.offset) >> PAGE_SHIFT) + page_offset; else { page = ttm->pages[page_offset]; if (unlikely(!page && i == 0)) { retval = VM_FAULT_OOM; goto out_io_unlock; } else if (unlikely(!page)) { break; } page->mapping = vma->vm_file->f_mapping; page->index = drm_vma_node_start(&bo->vma_node) + page_offset; pfn = page_to_pfn(page); } if (vma->vm_flags & VM_MIXEDMAP) ret = vm_insert_mixed(&cvma, address, pfn); else ret = vm_insert_pfn(&cvma, address, pfn); /* * Somebody beat us to this PTE or prefaulting to * an already populated PTE, or prefaulting error. */ if (unlikely((ret == -EBUSY) || (ret != 0 && i > 0))) break; else if (unlikely(ret != 0)) { retval = (ret == -ENOMEM) ? VM_FAULT_OOM : VM_FAULT_SIGBUS; goto out_io_unlock; } address += PAGE_SIZE; if (unlikely(++page_offset >= page_last)) break; } out_io_unlock: ttm_mem_io_unlock(man); out_unlock: ttm_bo_unreserve(bo); return retval; } static void ttm_bo_vm_open(struct vm_area_struct *vma) { struct ttm_buffer_object *bo = (struct ttm_buffer_object *)vma->vm_private_data; WARN_ON(bo->bdev->dev_mapping != vma->vm_file->f_mapping); (void)ttm_bo_reference(bo); } static void ttm_bo_vm_close(struct vm_area_struct *vma) { struct ttm_buffer_object *bo = (struct ttm_buffer_object *)vma->vm_private_data; ttm_bo_unref(&bo); vma->vm_private_data = NULL; } static const struct vm_operations_struct ttm_bo_vm_ops = { .fault = ttm_bo_vm_fault, .open = ttm_bo_vm_open, .close = ttm_bo_vm_close }; static struct ttm_buffer_object *ttm_bo_vm_lookup(struct ttm_bo_device *bdev, unsigned long offset, unsigned long pages) { struct drm_vma_offset_node *node; struct ttm_buffer_object *bo = NULL; drm_vma_offset_lock_lookup(&bdev->vma_manager); node = drm_vma_offset_lookup_locked(&bdev->vma_manager, offset, pages); if (likely(node)) { bo = container_of(node, struct ttm_buffer_object, vma_node); if (!kref_get_unless_zero(&bo->kref)) bo = NULL; } drm_vma_offset_unlock_lookup(&bdev->vma_manager); if (!bo) pr_err("Could not find buffer object to map\n"); return bo; } int ttm_bo_mmap(struct file *filp, struct vm_area_struct *vma, struct ttm_bo_device *bdev) { struct ttm_bo_driver *driver; struct ttm_buffer_object *bo; int ret; bo = ttm_bo_vm_lookup(bdev, vma->vm_pgoff, vma_pages(vma)); if (unlikely(!bo)) return -EINVAL; driver = bo->bdev->driver; if (unlikely(!driver->verify_access)) { ret = -EPERM; goto out_unref; } ret = driver->verify_access(bo, filp); if (unlikely(ret != 0)) goto out_unref; vma->vm_ops = &ttm_bo_vm_ops; /* * Note: We're transferring the bo reference to * vma->vm_private_data here. */ vma->vm_private_data = bo; /* * We'd like to use VM_PFNMAP on shared mappings, where * (vma->vm_flags & VM_SHARED) != 0, for performance reasons, * but for some reason VM_PFNMAP + x86 PAT + write-combine is very * bad for performance. Until that has been sorted out, use * VM_MIXEDMAP on all mappings. See freedesktop.org bug #75719 */ vma->vm_flags |= VM_MIXEDMAP; vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP; return 0; out_unref: ttm_bo_unref(&bo); return ret; } EXPORT_SYMBOL(ttm_bo_mmap); int ttm_fbdev_mmap(struct vm_area_struct *vma, struct ttm_buffer_object *bo) { if (vma->vm_pgoff != 0) return -EACCES; vma->vm_ops = &ttm_bo_vm_ops; vma->vm_private_data = ttm_bo_reference(bo); vma->vm_flags |= VM_MIXEDMAP; vma->vm_flags |= VM_IO | VM_DONTEXPAND; return 0; } EXPORT_SYMBOL(ttm_fbdev_mmap);