2 * Copyright (C) 2013-2016 Luigi Rizzo
3 * Copyright (C) 2013-2016 Giuseppe Lettieri
4 * Copyright (C) 2013-2016 Vincenzo Maffione
5 * Copyright (C) 2015 Stefano Garzarella
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * ptnetmap_memdev: device used to expose memory into the guest VM
38 * These macros are used in the hypervisor frontend (QEMU, bhyve) and in the
39 * guest device driver.
42 /* PCI identifiers and PCI BARs for the ptnetmap memdev
43 * and ptnetmap network interface. */
44 #define PTNETMAP_MEMDEV_NAME "ptnetmap-memdev"
45 #define PTNETMAP_PCI_VENDOR_ID 0x1b36 /* QEMU virtual devices */
46 #define PTNETMAP_PCI_DEVICE_ID 0x000c /* memory device */
47 #define PTNETMAP_PCI_NETIF_ID 0x000d /* ptnet network interface */
48 #define PTNETMAP_IO_PCI_BAR 0
49 #define PTNETMAP_MEM_PCI_BAR 1
50 #define PTNETMAP_MSIX_PCI_BAR 2
52 /* Registers for the ptnetmap memdev */
53 #define PTNET_MDEV_IO_MEMSIZE_LO 0 /* netmap memory size (low) */
54 #define PTNET_MDEV_IO_MEMSIZE_HI 4 /* netmap_memory_size (high) */
55 #define PTNET_MDEV_IO_MEMID 8 /* memory allocator ID in the host */
56 #define PTNET_MDEV_IO_IF_POOL_OFS 64
57 #define PTNET_MDEV_IO_IF_POOL_OBJNUM 68
58 #define PTNET_MDEV_IO_IF_POOL_OBJSZ 72
59 #define PTNET_MDEV_IO_RING_POOL_OFS 76
60 #define PTNET_MDEV_IO_RING_POOL_OBJNUM 80
61 #define PTNET_MDEV_IO_RING_POOL_OBJSZ 84
62 #define PTNET_MDEV_IO_BUF_POOL_OFS 88
63 #define PTNET_MDEV_IO_BUF_POOL_OBJNUM 92
64 #define PTNET_MDEV_IO_BUF_POOL_OBJSZ 96
65 #define PTNET_MDEV_IO_END 100
68 * ptnetmap configuration
70 * The ptnet kthreads (running in host kernel-space) need to be configured
71 * in order to know how to intercept guest kicks (I/O register writes) and
72 * how to inject MSI-X interrupts to the guest. The configuration may vary
73 * depending on the hypervisor. Currently, we support QEMU/KVM on Linux and
74 * and bhyve on FreeBSD.
75 * The configuration is passed by the hypervisor to the host netmap module
76 * by means of an ioctl() with nr_cmd=NETMAP_PT_HOST_CREATE, and it is
77 * specified by the ptnetmap_cfg struct. This struct contains an header
78 * with general informations and an array of entries whose size depends
79 * on the hypervisor. The NETMAP_PT_HOST_CREATE command is issued every
80 * time the kthreads are started.
83 #define PTNETMAP_CFGTYPE_QEMU 0x1
84 #define PTNETMAP_CFGTYPE_BHYVE 0x2
85 uint16_t cfgtype; /* how to interpret the cfg entries */
86 uint16_t entry_size; /* size of a config entry */
87 uint32_t num_rings; /* number of config entries */
88 void *csb_gh; /* CSB for guest --> host communication */
89 void *csb_hg; /* CSB for host --> guest communication */
90 /* Configuration entries are allocated right after the struct. */
93 /* Configuration of a ptnetmap ring for QEMU. */
94 struct ptnetmap_cfgentry_qemu {
95 uint32_t ioeventfd; /* to intercept guest register access */
96 uint32_t irqfd; /* to inject guest interrupts */
99 /* Configuration of a ptnetmap ring for bhyve. */
100 struct ptnetmap_cfgentry_bhyve {
101 uint64_t wchan; /* tsleep() parameter, to wake up kthread */
102 uint32_t ioctl_fd; /* ioctl fd */
103 /* ioctl parameters to send irq */
105 /* vmm.ko MSIX parameters for IOCTL */
113 * Pass a pointer to a userspace buffer to be passed to kernelspace for write
114 * or read. Used by NETMAP_PT_HOST_CREATE.
118 nmreq_pointer_put(struct nmreq *nmr, void *userptr)
120 uintptr_t *pp = (uintptr_t *)&nmr->nr_arg1;
121 *pp = (uintptr_t)userptr;
125 nmreq_pointer_get(const struct nmreq *nmr)
127 const uintptr_t *pp = (const uintptr_t *)&nmr->nr_arg1;
131 /* ptnetmap features */
132 #define PTNETMAP_F_VNET_HDR 1
134 /* I/O registers for the ptnet device. */
135 #define PTNET_IO_PTFEAT 0
136 #define PTNET_IO_PTCTL 4
137 #define PTNET_IO_MAC_LO 8
138 #define PTNET_IO_MAC_HI 12
139 #define PTNET_IO_CSBBAH 16 /* deprecated */
140 #define PTNET_IO_CSBBAL 20 /* deprecated */
141 #define PTNET_IO_NIFP_OFS 24
142 #define PTNET_IO_NUM_TX_RINGS 28
143 #define PTNET_IO_NUM_RX_RINGS 32
144 #define PTNET_IO_NUM_TX_SLOTS 36
145 #define PTNET_IO_NUM_RX_SLOTS 40
146 #define PTNET_IO_VNET_HDR_LEN 44
147 #define PTNET_IO_HOSTMEMID 48
148 #define PTNET_IO_CSB_GH_BAH 52
149 #define PTNET_IO_CSB_GH_BAL 56
150 #define PTNET_IO_CSB_HG_BAH 60
151 #define PTNET_IO_CSB_HG_BAL 64
152 #define PTNET_IO_END 68
153 #define PTNET_IO_KICK_BASE 128
154 #define PTNET_IO_MASK 0xff
156 /* ptnetmap control commands (values for PTCTL register) */
157 #define PTNETMAP_PTCTL_CREATE 1
158 #define PTNETMAP_PTCTL_DELETE 2
160 /* ptnetmap synchronization variables shared between guest and host */
161 struct ptnet_csb_gh {
162 uint32_t head; /* GW+ HR+ the head of the guest netmap_ring */
163 uint32_t cur; /* GW+ HR+ the cur of the guest netmap_ring */
164 uint32_t guest_need_kick; /* GW+ HR+ host-->guest notification enable */
165 uint32_t sync_flags; /* GW+ HR+ the flags of the guest [tx|rx]sync() */
166 char pad[48]; /* pad to a 64 bytes cacheline */
168 struct ptnet_csb_hg {
169 uint32_t hwcur; /* GR+ HW+ the hwcur of the host netmap_kring */
170 uint32_t hwtail; /* GR+ HW+ the hwtail of the host netmap_kring */
171 uint32_t host_need_kick; /* GR+ HW+ guest-->host notification enable */
175 #ifdef WITH_PTNETMAP_GUEST
177 /* ptnetmap_memdev routines used to talk with ptnetmap_memdev device driver */
178 struct ptnetmap_memdev;
179 int nm_os_pt_memdev_iomap(struct ptnetmap_memdev *, vm_paddr_t *, void **,
181 void nm_os_pt_memdev_iounmap(struct ptnetmap_memdev *);
182 uint32_t nm_os_pt_memdev_ioread(struct ptnetmap_memdev *, unsigned int);
184 /* Guest driver: Write kring pointers (cur, head) to the CSB.
185 * This routine is coupled with ptnetmap_host_read_kring_csb(). */
187 ptnetmap_guest_write_kring_csb(struct ptnet_csb_gh *ptr, uint32_t cur,
191 * We need to write cur and head to the CSB but we cannot do it atomically.
192 * There is no way we can prevent the host from reading the updated value
193 * of one of the two and the old value of the other. However, if we make
194 * sure that the host never reads a value of head more recent than the
195 * value of cur we are safe. We can allow the host to read a value of cur
196 * more recent than the value of head, since in the netmap ring cur can be
197 * ahead of head and cur cannot wrap around head because it must be behind
198 * tail. Inverting the order of writes below could instead result into the
199 * host to think head went ahead of cur, which would cause the sync
202 * The following memory barrier scheme is used to make this happen:
206 * STORE(cur) LOAD(head)
207 * mb() <-----------> mb()
208 * STORE(head) LOAD(cur)
215 /* Guest driver: Read kring pointers (hwcur, hwtail) from the CSB.
216 * This routine is coupled with ptnetmap_host_write_kring_csb(). */
218 ptnetmap_guest_read_kring_csb(struct ptnet_csb_hg *pthg, struct netmap_kring *kring)
221 * We place a memory barrier to make sure that the update of hwtail never
222 * overtakes the update of hwcur.
223 * (see explanation in ptnetmap_host_write_kring_csb).
225 kring->nr_hwtail = pthg->hwtail;
227 kring->nr_hwcur = pthg->hwcur;
230 #endif /* WITH_PTNETMAP_GUEST */
232 #ifdef WITH_PTNETMAP_HOST
234 * ptnetmap kernel thread routines
237 /* Functions to read and write CSB fields in the host */
239 #define CSB_READ(csb, field, r) (get_user(r, &csb->field))
240 #define CSB_WRITE(csb, field, v) (put_user(v, &csb->field))
242 #define CSB_READ(csb, field, r) (r = fuword32(&csb->field))
243 #define CSB_WRITE(csb, field, v) (suword32(&csb->field, v))
246 /* Host netmap: Write kring pointers (hwcur, hwtail) to the CSB.
247 * This routine is coupled with ptnetmap_guest_read_kring_csb(). */
249 ptnetmap_host_write_kring_csb(struct ptnet_csb_hg __user *ptr, uint32_t hwcur,
253 * The same scheme used in ptnetmap_guest_write_kring_csb() applies here.
254 * We allow the guest to read a value of hwcur more recent than the value
255 * of hwtail, since this would anyway result in a consistent view of the
256 * ring state (and hwcur can never wraparound hwtail, since hwcur must be
259 * The following memory barrier scheme is used to make this happen:
263 * STORE(hwcur) LOAD(hwtail)
264 * mb() <-------------> mb()
265 * STORE(hwtail) LOAD(hwcur)
267 CSB_WRITE(ptr, hwcur, hwcur);
269 CSB_WRITE(ptr, hwtail, hwtail);
272 /* Host netmap: Read kring pointers (head, cur, sync_flags) from the CSB.
273 * This routine is coupled with ptnetmap_guest_write_kring_csb(). */
275 ptnetmap_host_read_kring_csb(struct ptnet_csb_gh __user *ptr,
276 struct netmap_ring *shadow_ring,
280 * We place a memory barrier to make sure that the update of head never
281 * overtakes the update of cur.
282 * (see explanation in ptnetmap_guest_write_kring_csb).
284 CSB_READ(ptr, head, shadow_ring->head);
286 CSB_READ(ptr, cur, shadow_ring->cur);
287 CSB_READ(ptr, sync_flags, shadow_ring->flags);
290 #endif /* WITH_PTNETMAP_HOST */
292 #endif /* NETMAP_VIRT_H */