1253440Sgrehan/*- 2253440Sgrehan * Copyright (c) 2013 Chris Torek <torek @ torek net> 3253440Sgrehan * All rights reserved. 4253440Sgrehan * 5253440Sgrehan * Redistribution and use in source and binary forms, with or without 6253440Sgrehan * modification, are permitted provided that the following conditions 7253440Sgrehan * are met: 8253440Sgrehan * 1. Redistributions of source code must retain the above copyright 9253440Sgrehan * notice, this list of conditions and the following disclaimer. 10253440Sgrehan * 2. Redistributions in binary form must reproduce the above copyright 11253440Sgrehan * notice, this list of conditions and the following disclaimer in the 12253440Sgrehan * documentation and/or other materials provided with the distribution. 13253440Sgrehan * 14253440Sgrehan * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15253440Sgrehan * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16253440Sgrehan * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17253440Sgrehan * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18253440Sgrehan * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19253440Sgrehan * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20253440Sgrehan * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21253440Sgrehan * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22253440Sgrehan * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23253440Sgrehan * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24253440Sgrehan * SUCH DAMAGE. 25253440Sgrehan */ 26253440Sgrehan 27253440Sgrehan#include <sys/cdefs.h> 28253440Sgrehan__FBSDID("$FreeBSD: releng/10.3/usr.sbin/bhyve/virtio.c 284900 2015-06-28 03:22:26Z neel $"); 29253440Sgrehan 30253440Sgrehan#include <sys/param.h> 31253440Sgrehan#include <sys/uio.h> 32253440Sgrehan 33253440Sgrehan#include <stdio.h> 34253440Sgrehan#include <stdint.h> 35253440Sgrehan#include <pthread.h> 36276349Sneel#include <pthread_np.h> 37253440Sgrehan 38253440Sgrehan#include "bhyverun.h" 39253440Sgrehan#include "pci_emul.h" 40253440Sgrehan#include "virtio.h" 41253440Sgrehan 42253440Sgrehan/* 43253440Sgrehan * Functions for dealing with generalized "virtual devices" as 44253440Sgrehan * defined by <https://www.google.com/#output=search&q=virtio+spec> 45253440Sgrehan */ 46253440Sgrehan 47253440Sgrehan/* 48253440Sgrehan * In case we decide to relax the "virtio softc comes at the 49253440Sgrehan * front of virtio-based device softc" constraint, let's use 50253440Sgrehan * this to convert. 51253440Sgrehan */ 52253440Sgrehan#define DEV_SOFTC(vs) ((void *)(vs)) 53253440Sgrehan 54253440Sgrehan/* 55253440Sgrehan * Link a virtio_softc to its constants, the device softc, and 56253440Sgrehan * the PCI emulation. 57253440Sgrehan */ 58253440Sgrehanvoid 59253440Sgrehanvi_softc_linkup(struct virtio_softc *vs, struct virtio_consts *vc, 60253440Sgrehan void *dev_softc, struct pci_devinst *pi, 61253440Sgrehan struct vqueue_info *queues) 62253440Sgrehan{ 63253440Sgrehan int i; 64253440Sgrehan 65253440Sgrehan /* vs and dev_softc addresses must match */ 66253440Sgrehan assert((void *)vs == dev_softc); 67253440Sgrehan vs->vs_vc = vc; 68253440Sgrehan vs->vs_pi = pi; 69253440Sgrehan pi->pi_arg = vs; 70253440Sgrehan 71253440Sgrehan vs->vs_queues = queues; 72253440Sgrehan for (i = 0; i < vc->vc_nvq; i++) { 73253440Sgrehan queues[i].vq_vs = vs; 74253440Sgrehan queues[i].vq_num = i; 75253440Sgrehan } 76253440Sgrehan} 77253440Sgrehan 78253440Sgrehan/* 79253440Sgrehan * Reset device (device-wide). This erases all queues, i.e., 80253440Sgrehan * all the queues become invalid (though we don't wipe out the 81253440Sgrehan * internal pointers, we just clear the VQ_ALLOC flag). 82253440Sgrehan * 83253440Sgrehan * It resets negotiated features to "none". 84253440Sgrehan * 85253440Sgrehan * If MSI-X is enabled, this also resets all the vectors to NO_VECTOR. 86253440Sgrehan */ 87253440Sgrehanvoid 88253440Sgrehanvi_reset_dev(struct virtio_softc *vs) 89253440Sgrehan{ 90253440Sgrehan struct vqueue_info *vq; 91253440Sgrehan int i, nvq; 92253440Sgrehan 93276349Sneel if (vs->vs_mtx) 94276349Sneel assert(pthread_mutex_isowned_np(vs->vs_mtx)); 95276349Sneel 96253440Sgrehan nvq = vs->vs_vc->vc_nvq; 97253440Sgrehan for (vq = vs->vs_queues, i = 0; i < nvq; vq++, i++) { 98253440Sgrehan vq->vq_flags = 0; 99253440Sgrehan vq->vq_last_avail = 0; 100280743Smav vq->vq_save_used = 0; 101253440Sgrehan vq->vq_pfn = 0; 102253440Sgrehan vq->vq_msix_idx = VIRTIO_MSI_NO_VECTOR; 103253440Sgrehan } 104253440Sgrehan vs->vs_negotiated_caps = 0; 105253440Sgrehan vs->vs_curq = 0; 106253440Sgrehan /* vs->vs_status = 0; -- redundant */ 107267393Sjhb if (vs->vs_isr) 108267393Sjhb pci_lintr_deassert(vs->vs_pi); 109253440Sgrehan vs->vs_isr = 0; 110253440Sgrehan vs->vs_msix_cfg_idx = VIRTIO_MSI_NO_VECTOR; 111253440Sgrehan} 112253440Sgrehan 113253440Sgrehan/* 114253440Sgrehan * Set I/O BAR (usually 0) to map PCI config registers. 115253440Sgrehan */ 116253440Sgrehanvoid 117253440Sgrehanvi_set_io_bar(struct virtio_softc *vs, int barnum) 118253440Sgrehan{ 119253440Sgrehan size_t size; 120253440Sgrehan 121253440Sgrehan /* 122253440Sgrehan * ??? should we use CFG0 if MSI-X is disabled? 123253440Sgrehan * Existing code did not... 124253440Sgrehan */ 125253440Sgrehan size = VTCFG_R_CFG1 + vs->vs_vc->vc_cfgsize; 126253440Sgrehan pci_emul_alloc_bar(vs->vs_pi, barnum, PCIBAR_IO, size); 127253440Sgrehan} 128253440Sgrehan 129253440Sgrehan/* 130253440Sgrehan * Initialize MSI-X vector capabilities if we're to use MSI-X, 131253440Sgrehan * or MSI capabilities if not. 132253440Sgrehan * 133253440Sgrehan * We assume we want one MSI-X vector per queue, here, plus one 134253440Sgrehan * for the config vec. 135253440Sgrehan */ 136253440Sgrehanint 137253440Sgrehanvi_intr_init(struct virtio_softc *vs, int barnum, int use_msix) 138253440Sgrehan{ 139253440Sgrehan int nvec; 140253440Sgrehan 141253440Sgrehan if (use_msix) { 142253440Sgrehan vs->vs_flags |= VIRTIO_USE_MSIX; 143276349Sneel VS_LOCK(vs); 144253440Sgrehan vi_reset_dev(vs); /* set all vectors to NO_VECTOR */ 145276349Sneel VS_UNLOCK(vs); 146253440Sgrehan nvec = vs->vs_vc->vc_nvq + 1; 147253440Sgrehan if (pci_emul_add_msixcap(vs->vs_pi, nvec, barnum)) 148253440Sgrehan return (1); 149267393Sjhb } else 150253440Sgrehan vs->vs_flags &= ~VIRTIO_USE_MSIX; 151284899Sneel 152267393Sjhb /* Only 1 MSI vector for bhyve */ 153267393Sjhb pci_emul_add_msicap(vs->vs_pi, 1); 154284899Sneel 155284899Sneel /* Legacy interrupts are mandatory for virtio devices */ 156284899Sneel pci_lintr_request(vs->vs_pi); 157284899Sneel 158253440Sgrehan return (0); 159253440Sgrehan} 160253440Sgrehan 161253440Sgrehan/* 162253440Sgrehan * Initialize the currently-selected virtio queue (vs->vs_curq). 163253440Sgrehan * The guest just gave us a page frame number, from which we can 164253440Sgrehan * calculate the addresses of the queue. 165253440Sgrehan */ 166253440Sgrehanvoid 167253440Sgrehanvi_vq_init(struct virtio_softc *vs, uint32_t pfn) 168253440Sgrehan{ 169253440Sgrehan struct vqueue_info *vq; 170253440Sgrehan uint64_t phys; 171253440Sgrehan size_t size; 172253440Sgrehan char *base; 173253440Sgrehan 174253440Sgrehan vq = &vs->vs_queues[vs->vs_curq]; 175253440Sgrehan vq->vq_pfn = pfn; 176266592Sjhb phys = (uint64_t)pfn << VRING_PFN; 177253440Sgrehan size = vring_size(vq->vq_qsize); 178253440Sgrehan base = paddr_guest2host(vs->vs_pi->pi_vmctx, phys, size); 179253440Sgrehan 180253440Sgrehan /* First page(s) are descriptors... */ 181253440Sgrehan vq->vq_desc = (struct virtio_desc *)base; 182253440Sgrehan base += vq->vq_qsize * sizeof(struct virtio_desc); 183253440Sgrehan 184253440Sgrehan /* ... immediately followed by "avail" ring (entirely uint16_t's) */ 185253440Sgrehan vq->vq_avail = (struct vring_avail *)base; 186253440Sgrehan base += (2 + vq->vq_qsize + 1) * sizeof(uint16_t); 187253440Sgrehan 188253440Sgrehan /* Then it's rounded up to the next page... */ 189253440Sgrehan base = (char *)roundup2((uintptr_t)base, VRING_ALIGN); 190253440Sgrehan 191253440Sgrehan /* ... and the last page(s) are the used ring. */ 192253440Sgrehan vq->vq_used = (struct vring_used *)base; 193253440Sgrehan 194253440Sgrehan /* Mark queue as allocated, and start at 0 when we use it. */ 195253440Sgrehan vq->vq_flags = VQ_ALLOC; 196253440Sgrehan vq->vq_last_avail = 0; 197280743Smav vq->vq_save_used = 0; 198253440Sgrehan} 199253440Sgrehan 200253440Sgrehan/* 201253440Sgrehan * Helper inline for vq_getchain(): record the i'th "real" 202253440Sgrehan * descriptor. 203253440Sgrehan */ 204253440Sgrehanstatic inline void 205253440Sgrehan_vq_record(int i, volatile struct virtio_desc *vd, struct vmctx *ctx, 206253440Sgrehan struct iovec *iov, int n_iov, uint16_t *flags) { 207253440Sgrehan 208253440Sgrehan if (i >= n_iov) 209253440Sgrehan return; 210253440Sgrehan iov[i].iov_base = paddr_guest2host(ctx, vd->vd_addr, vd->vd_len); 211253440Sgrehan iov[i].iov_len = vd->vd_len; 212253440Sgrehan if (flags != NULL) 213253440Sgrehan flags[i] = vd->vd_flags; 214253440Sgrehan} 215253440Sgrehan#define VQ_MAX_DESCRIPTORS 512 /* see below */ 216253440Sgrehan 217253440Sgrehan/* 218253440Sgrehan * Examine the chain of descriptors starting at the "next one" to 219253440Sgrehan * make sure that they describe a sensible request. If so, return 220253440Sgrehan * the number of "real" descriptors that would be needed/used in 221253440Sgrehan * acting on this request. This may be smaller than the number of 222253440Sgrehan * available descriptors, e.g., if there are two available but 223253440Sgrehan * they are two separate requests, this just returns 1. Or, it 224253440Sgrehan * may be larger: if there are indirect descriptors involved, 225253440Sgrehan * there may only be one descriptor available but it may be an 226253440Sgrehan * indirect pointing to eight more. We return 8 in this case, 227253440Sgrehan * i.e., we do not count the indirect descriptors, only the "real" 228253440Sgrehan * ones. 229253440Sgrehan * 230253440Sgrehan * Basically, this vets the vd_flags and vd_next field of each 231253440Sgrehan * descriptor and tells you how many are involved. Since some may 232253440Sgrehan * be indirect, this also needs the vmctx (in the pci_devinst 233253440Sgrehan * at vs->vs_pi) so that it can find indirect descriptors. 234253440Sgrehan * 235253440Sgrehan * As we process each descriptor, we copy and adjust it (guest to 236253440Sgrehan * host address wise, also using the vmtctx) into the given iov[] 237253440Sgrehan * array (of the given size). If the array overflows, we stop 238253440Sgrehan * placing values into the array but keep processing descriptors, 239253440Sgrehan * up to VQ_MAX_DESCRIPTORS, before giving up and returning -1. 240253440Sgrehan * So you, the caller, must not assume that iov[] is as big as the 241253440Sgrehan * return value (you can process the same thing twice to allocate 242253440Sgrehan * a larger iov array if needed, or supply a zero length to find 243253440Sgrehan * out how much space is needed). 244253440Sgrehan * 245253440Sgrehan * If you want to verify the WRITE flag on each descriptor, pass a 246253440Sgrehan * non-NULL "flags" pointer to an array of "uint16_t" of the same size 247253440Sgrehan * as n_iov and we'll copy each vd_flags field after unwinding any 248253440Sgrehan * indirects. 249253440Sgrehan * 250253440Sgrehan * If some descriptor(s) are invalid, this prints a diagnostic message 251253440Sgrehan * and returns -1. If no descriptors are ready now it simply returns 0. 252253440Sgrehan * 253253440Sgrehan * You are assumed to have done a vq_ring_ready() if needed (note 254253440Sgrehan * that vq_has_descs() does one). 255253440Sgrehan */ 256253440Sgrehanint 257280743Smavvq_getchain(struct vqueue_info *vq, uint16_t *pidx, 258253440Sgrehan struct iovec *iov, int n_iov, uint16_t *flags) 259253440Sgrehan{ 260253440Sgrehan int i; 261253440Sgrehan u_int ndesc, n_indir; 262280743Smav u_int idx, next; 263253440Sgrehan volatile struct virtio_desc *vdir, *vindir, *vp; 264253440Sgrehan struct vmctx *ctx; 265253440Sgrehan struct virtio_softc *vs; 266253440Sgrehan const char *name; 267253440Sgrehan 268253440Sgrehan vs = vq->vq_vs; 269253440Sgrehan name = vs->vs_vc->vc_name; 270253440Sgrehan 271253440Sgrehan /* 272253440Sgrehan * Note: it's the responsibility of the guest not to 273253440Sgrehan * update vq->vq_avail->va_idx until all of the descriptors 274253440Sgrehan * the guest has written are valid (including all their 275253440Sgrehan * vd_next fields and vd_flags). 276253440Sgrehan * 277253440Sgrehan * Compute (last_avail - va_idx) in integers mod 2**16. This is 278253440Sgrehan * the number of descriptors the device has made available 279253440Sgrehan * since the last time we updated vq->vq_last_avail. 280253440Sgrehan * 281253440Sgrehan * We just need to do the subtraction as an unsigned int, 282253440Sgrehan * then trim off excess bits. 283253440Sgrehan */ 284253440Sgrehan idx = vq->vq_last_avail; 285253440Sgrehan ndesc = (uint16_t)((u_int)vq->vq_avail->va_idx - idx); 286253440Sgrehan if (ndesc == 0) 287253440Sgrehan return (0); 288253440Sgrehan if (ndesc > vq->vq_qsize) { 289253440Sgrehan /* XXX need better way to diagnose issues */ 290253440Sgrehan fprintf(stderr, 291253440Sgrehan "%s: ndesc (%u) out of range, driver confused?\r\n", 292253440Sgrehan name, (u_int)ndesc); 293253440Sgrehan return (-1); 294253440Sgrehan } 295253440Sgrehan 296253440Sgrehan /* 297253440Sgrehan * Now count/parse "involved" descriptors starting from 298253440Sgrehan * the head of the chain. 299253440Sgrehan * 300253440Sgrehan * To prevent loops, we could be more complicated and 301253440Sgrehan * check whether we're re-visiting a previously visited 302253440Sgrehan * index, but we just abort if the count gets excessive. 303253440Sgrehan */ 304253440Sgrehan ctx = vs->vs_pi->pi_vmctx; 305280743Smav *pidx = next = vq->vq_avail->va_ring[idx & (vq->vq_qsize - 1)]; 306280743Smav vq->vq_last_avail++; 307253440Sgrehan for (i = 0; i < VQ_MAX_DESCRIPTORS; next = vdir->vd_next) { 308253440Sgrehan if (next >= vq->vq_qsize) { 309253440Sgrehan fprintf(stderr, 310253440Sgrehan "%s: descriptor index %u out of range, " 311253440Sgrehan "driver confused?\r\n", 312253440Sgrehan name, next); 313253440Sgrehan return (-1); 314253440Sgrehan } 315253440Sgrehan vdir = &vq->vq_desc[next]; 316253440Sgrehan if ((vdir->vd_flags & VRING_DESC_F_INDIRECT) == 0) { 317253440Sgrehan _vq_record(i, vdir, ctx, iov, n_iov, flags); 318253440Sgrehan i++; 319284900Sneel } else if ((vs->vs_vc->vc_hv_caps & 320253440Sgrehan VIRTIO_RING_F_INDIRECT_DESC) == 0) { 321253440Sgrehan fprintf(stderr, 322253440Sgrehan "%s: descriptor has forbidden INDIRECT flag, " 323253440Sgrehan "driver confused?\r\n", 324253440Sgrehan name); 325253440Sgrehan return (-1); 326253440Sgrehan } else { 327253440Sgrehan n_indir = vdir->vd_len / 16; 328253440Sgrehan if ((vdir->vd_len & 0xf) || n_indir == 0) { 329253440Sgrehan fprintf(stderr, 330253440Sgrehan "%s: invalid indir len 0x%x, " 331253440Sgrehan "driver confused?\r\n", 332253440Sgrehan name, (u_int)vdir->vd_len); 333253440Sgrehan return (-1); 334253440Sgrehan } 335253440Sgrehan vindir = paddr_guest2host(ctx, 336253440Sgrehan vdir->vd_addr, vdir->vd_len); 337253440Sgrehan /* 338253440Sgrehan * Indirects start at the 0th, then follow 339253440Sgrehan * their own embedded "next"s until those run 340253440Sgrehan * out. Each one's indirect flag must be off 341253440Sgrehan * (we don't really have to check, could just 342253440Sgrehan * ignore errors...). 343253440Sgrehan */ 344253440Sgrehan next = 0; 345253440Sgrehan for (;;) { 346253440Sgrehan vp = &vindir[next]; 347253440Sgrehan if (vp->vd_flags & VRING_DESC_F_INDIRECT) { 348253440Sgrehan fprintf(stderr, 349253440Sgrehan "%s: indirect desc has INDIR flag," 350253440Sgrehan " driver confused?\r\n", 351253440Sgrehan name); 352253440Sgrehan return (-1); 353253440Sgrehan } 354253440Sgrehan _vq_record(i, vp, ctx, iov, n_iov, flags); 355253440Sgrehan if (++i > VQ_MAX_DESCRIPTORS) 356253440Sgrehan goto loopy; 357253440Sgrehan if ((vp->vd_flags & VRING_DESC_F_NEXT) == 0) 358253440Sgrehan break; 359253440Sgrehan next = vp->vd_next; 360253440Sgrehan if (next >= n_indir) { 361253440Sgrehan fprintf(stderr, 362253440Sgrehan "%s: invalid next %u > %u, " 363253440Sgrehan "driver confused?\r\n", 364253440Sgrehan name, (u_int)next, n_indir); 365253440Sgrehan return (-1); 366253440Sgrehan } 367253440Sgrehan } 368253440Sgrehan } 369253440Sgrehan if ((vdir->vd_flags & VRING_DESC_F_NEXT) == 0) 370253440Sgrehan return (i); 371253440Sgrehan } 372253440Sgrehanloopy: 373253440Sgrehan fprintf(stderr, 374253440Sgrehan "%s: descriptor loop? count > %d - driver confused?\r\n", 375253440Sgrehan name, i); 376253440Sgrehan return (-1); 377253440Sgrehan} 378253440Sgrehan 379253440Sgrehan/* 380280743Smav * Return the currently-first request chain back to the available queue. 381253440Sgrehan * 382253440Sgrehan * (This chain is the one you handled when you called vq_getchain() 383253440Sgrehan * and used its positive return value.) 384253440Sgrehan */ 385253440Sgrehanvoid 386280743Smavvq_retchain(struct vqueue_info *vq) 387253440Sgrehan{ 388280743Smav 389280743Smav vq->vq_last_avail--; 390280743Smav} 391280743Smav 392280743Smav/* 393280743Smav * Return specified request chain to the guest, setting its I/O length 394280743Smav * to the provided value. 395280743Smav * 396280743Smav * (This chain is the one you handled when you called vq_getchain() 397280743Smav * and used its positive return value.) 398280743Smav */ 399280743Smavvoid 400280743Smavvq_relchain(struct vqueue_info *vq, uint16_t idx, uint32_t iolen) 401280743Smav{ 402280743Smav uint16_t uidx, mask; 403253440Sgrehan volatile struct vring_used *vuh; 404253440Sgrehan volatile struct virtio_used *vue; 405253440Sgrehan 406253440Sgrehan /* 407253440Sgrehan * Notes: 408253440Sgrehan * - mask is N-1 where N is a power of 2 so computes x % N 409253440Sgrehan * - vuh points to the "used" data shared with guest 410253440Sgrehan * - vue points to the "used" ring entry we want to update 411253440Sgrehan * - head is the same value we compute in vq_iovecs(). 412253440Sgrehan * 413253440Sgrehan * (I apologize for the two fields named vu_idx; the 414253440Sgrehan * virtio spec calls the one that vue points to, "id"...) 415253440Sgrehan */ 416253440Sgrehan mask = vq->vq_qsize - 1; 417253440Sgrehan vuh = vq->vq_used; 418253440Sgrehan 419253440Sgrehan uidx = vuh->vu_idx; 420253440Sgrehan vue = &vuh->vu_ring[uidx++ & mask]; 421280743Smav vue->vu_idx = idx; 422253440Sgrehan vue->vu_tlen = iolen; 423253440Sgrehan vuh->vu_idx = uidx; 424253440Sgrehan} 425253440Sgrehan 426253440Sgrehan/* 427253440Sgrehan * Driver has finished processing "available" chains and calling 428253440Sgrehan * vq_relchain on each one. If driver used all the available 429253440Sgrehan * chains, used_all should be set. 430253440Sgrehan * 431253440Sgrehan * If the "used" index moved we may need to inform the guest, i.e., 432253440Sgrehan * deliver an interrupt. Even if the used index did NOT move we 433253440Sgrehan * may need to deliver an interrupt, if the avail ring is empty and 434253440Sgrehan * we are supposed to interrupt on empty. 435253440Sgrehan * 436253440Sgrehan * Note that used_all_avail is provided by the caller because it's 437253440Sgrehan * a snapshot of the ring state when he decided to finish interrupt 438253440Sgrehan * processing -- it's possible that descriptors became available after 439253440Sgrehan * that point. (It's also typically a constant 1/True as well.) 440253440Sgrehan */ 441253440Sgrehanvoid 442253440Sgrehanvq_endchains(struct vqueue_info *vq, int used_all_avail) 443253440Sgrehan{ 444253440Sgrehan struct virtio_softc *vs; 445253440Sgrehan uint16_t event_idx, new_idx, old_idx; 446253440Sgrehan int intr; 447253440Sgrehan 448253440Sgrehan /* 449253440Sgrehan * Interrupt generation: if we're using EVENT_IDX, 450253440Sgrehan * interrupt if we've crossed the event threshold. 451253440Sgrehan * Otherwise interrupt is generated if we added "used" entries, 452253440Sgrehan * but suppressed by VRING_AVAIL_F_NO_INTERRUPT. 453253440Sgrehan * 454253440Sgrehan * In any case, though, if NOTIFY_ON_EMPTY is set and the 455253440Sgrehan * entire avail was processed, we need to interrupt always. 456253440Sgrehan */ 457253440Sgrehan vs = vq->vq_vs; 458253440Sgrehan old_idx = vq->vq_save_used; 459280743Smav vq->vq_save_used = new_idx = vq->vq_used->vu_idx; 460253440Sgrehan if (used_all_avail && 461253440Sgrehan (vs->vs_negotiated_caps & VIRTIO_F_NOTIFY_ON_EMPTY)) 462253440Sgrehan intr = 1; 463270159Sgrehan else if (vs->vs_negotiated_caps & VIRTIO_RING_F_EVENT_IDX) { 464253440Sgrehan event_idx = VQ_USED_EVENT_IDX(vq); 465253440Sgrehan /* 466253440Sgrehan * This calculation is per docs and the kernel 467253440Sgrehan * (see src/sys/dev/virtio/virtio_ring.h). 468253440Sgrehan */ 469253440Sgrehan intr = (uint16_t)(new_idx - event_idx - 1) < 470253440Sgrehan (uint16_t)(new_idx - old_idx); 471253440Sgrehan } else { 472253440Sgrehan intr = new_idx != old_idx && 473253440Sgrehan !(vq->vq_avail->va_flags & VRING_AVAIL_F_NO_INTERRUPT); 474253440Sgrehan } 475253440Sgrehan if (intr) 476253440Sgrehan vq_interrupt(vs, vq); 477253440Sgrehan} 478253440Sgrehan 479253440Sgrehan/* Note: these are in sorted order to make for a fast search */ 480253440Sgrehanstatic struct config_reg { 481253440Sgrehan uint16_t cr_offset; /* register offset */ 482253440Sgrehan uint8_t cr_size; /* size (bytes) */ 483253440Sgrehan uint8_t cr_ro; /* true => reg is read only */ 484253440Sgrehan const char *cr_name; /* name of reg */ 485253440Sgrehan} config_regs[] = { 486253440Sgrehan { VTCFG_R_HOSTCAP, 4, 1, "HOSTCAP" }, 487253440Sgrehan { VTCFG_R_GUESTCAP, 4, 0, "GUESTCAP" }, 488253440Sgrehan { VTCFG_R_PFN, 4, 0, "PFN" }, 489253440Sgrehan { VTCFG_R_QNUM, 2, 1, "QNUM" }, 490253440Sgrehan { VTCFG_R_QSEL, 2, 0, "QSEL" }, 491253440Sgrehan { VTCFG_R_QNOTIFY, 2, 0, "QNOTIFY" }, 492253440Sgrehan { VTCFG_R_STATUS, 1, 0, "STATUS" }, 493253440Sgrehan { VTCFG_R_ISR, 1, 0, "ISR" }, 494253440Sgrehan { VTCFG_R_CFGVEC, 2, 0, "CFGVEC" }, 495253440Sgrehan { VTCFG_R_QVEC, 2, 0, "QVEC" }, 496253440Sgrehan}; 497253440Sgrehan 498253440Sgrehanstatic inline struct config_reg * 499253440Sgrehanvi_find_cr(int offset) { 500253440Sgrehan u_int hi, lo, mid; 501253440Sgrehan struct config_reg *cr; 502253440Sgrehan 503253440Sgrehan lo = 0; 504253440Sgrehan hi = sizeof(config_regs) / sizeof(*config_regs) - 1; 505253440Sgrehan while (hi >= lo) { 506253440Sgrehan mid = (hi + lo) >> 1; 507253440Sgrehan cr = &config_regs[mid]; 508253440Sgrehan if (cr->cr_offset == offset) 509253440Sgrehan return (cr); 510253440Sgrehan if (cr->cr_offset < offset) 511253440Sgrehan lo = mid + 1; 512253440Sgrehan else 513253440Sgrehan hi = mid - 1; 514253440Sgrehan } 515253440Sgrehan return (NULL); 516253440Sgrehan} 517253440Sgrehan 518253440Sgrehan/* 519253440Sgrehan * Handle pci config space reads. 520253440Sgrehan * If it's to the MSI-X info, do that. 521253440Sgrehan * If it's part of the virtio standard stuff, do that. 522253440Sgrehan * Otherwise dispatch to the actual driver. 523253440Sgrehan */ 524253440Sgrehanuint64_t 525253440Sgrehanvi_pci_read(struct vmctx *ctx, int vcpu, struct pci_devinst *pi, 526253440Sgrehan int baridx, uint64_t offset, int size) 527253440Sgrehan{ 528253440Sgrehan struct virtio_softc *vs = pi->pi_arg; 529253440Sgrehan struct virtio_consts *vc; 530253440Sgrehan struct config_reg *cr; 531253440Sgrehan uint64_t virtio_config_size, max; 532253440Sgrehan const char *name; 533253440Sgrehan uint32_t newoff; 534253440Sgrehan uint32_t value; 535253440Sgrehan int error; 536253440Sgrehan 537253440Sgrehan if (vs->vs_flags & VIRTIO_USE_MSIX) { 538253440Sgrehan if (baridx == pci_msix_table_bar(pi) || 539253440Sgrehan baridx == pci_msix_pba_bar(pi)) { 540253440Sgrehan return (pci_emul_msix_tread(pi, offset, size)); 541253440Sgrehan } 542253440Sgrehan } 543253440Sgrehan 544253440Sgrehan /* XXX probably should do something better than just assert() */ 545253440Sgrehan assert(baridx == 0); 546253440Sgrehan 547253440Sgrehan if (vs->vs_mtx) 548253440Sgrehan pthread_mutex_lock(vs->vs_mtx); 549253440Sgrehan 550253440Sgrehan vc = vs->vs_vc; 551253440Sgrehan name = vc->vc_name; 552253440Sgrehan value = size == 1 ? 0xff : size == 2 ? 0xffff : 0xffffffff; 553253440Sgrehan 554253440Sgrehan if (size != 1 && size != 2 && size != 4) 555253440Sgrehan goto bad; 556253440Sgrehan 557253440Sgrehan if (pci_msix_enabled(pi)) 558253440Sgrehan virtio_config_size = VTCFG_R_CFG1; 559253440Sgrehan else 560253440Sgrehan virtio_config_size = VTCFG_R_CFG0; 561253440Sgrehan 562253440Sgrehan if (offset >= virtio_config_size) { 563253440Sgrehan /* 564253440Sgrehan * Subtract off the standard size (including MSI-X 565253440Sgrehan * registers if enabled) and dispatch to underlying driver. 566253440Sgrehan * If that fails, fall into general code. 567253440Sgrehan */ 568253440Sgrehan newoff = offset - virtio_config_size; 569253440Sgrehan max = vc->vc_cfgsize ? vc->vc_cfgsize : 0x100000000; 570253440Sgrehan if (newoff + size > max) 571253440Sgrehan goto bad; 572253440Sgrehan error = (*vc->vc_cfgread)(DEV_SOFTC(vs), newoff, size, &value); 573253440Sgrehan if (!error) 574253440Sgrehan goto done; 575253440Sgrehan } 576253440Sgrehan 577253440Sgrehanbad: 578253440Sgrehan cr = vi_find_cr(offset); 579253440Sgrehan if (cr == NULL || cr->cr_size != size) { 580253440Sgrehan if (cr != NULL) { 581253440Sgrehan /* offset must be OK, so size must be bad */ 582253440Sgrehan fprintf(stderr, 583253440Sgrehan "%s: read from %s: bad size %d\r\n", 584253440Sgrehan name, cr->cr_name, size); 585253440Sgrehan } else { 586253440Sgrehan fprintf(stderr, 587253440Sgrehan "%s: read from bad offset/size %jd/%d\r\n", 588253440Sgrehan name, (uintmax_t)offset, size); 589253440Sgrehan } 590253440Sgrehan goto done; 591253440Sgrehan } 592253440Sgrehan 593253440Sgrehan switch (offset) { 594253440Sgrehan case VTCFG_R_HOSTCAP: 595253440Sgrehan value = vc->vc_hv_caps; 596253440Sgrehan break; 597253440Sgrehan case VTCFG_R_GUESTCAP: 598253440Sgrehan value = vs->vs_negotiated_caps; 599253440Sgrehan break; 600253440Sgrehan case VTCFG_R_PFN: 601253440Sgrehan if (vs->vs_curq < vc->vc_nvq) 602253440Sgrehan value = vs->vs_queues[vs->vs_curq].vq_pfn; 603253440Sgrehan break; 604253440Sgrehan case VTCFG_R_QNUM: 605253440Sgrehan value = vs->vs_curq < vc->vc_nvq ? 606253440Sgrehan vs->vs_queues[vs->vs_curq].vq_qsize : 0; 607253440Sgrehan break; 608253440Sgrehan case VTCFG_R_QSEL: 609253440Sgrehan value = vs->vs_curq; 610253440Sgrehan break; 611253440Sgrehan case VTCFG_R_QNOTIFY: 612253440Sgrehan value = 0; /* XXX */ 613253440Sgrehan break; 614253440Sgrehan case VTCFG_R_STATUS: 615253440Sgrehan value = vs->vs_status; 616253440Sgrehan break; 617253440Sgrehan case VTCFG_R_ISR: 618253440Sgrehan value = vs->vs_isr; 619253440Sgrehan vs->vs_isr = 0; /* a read clears this flag */ 620267393Sjhb if (value) 621267393Sjhb pci_lintr_deassert(pi); 622253440Sgrehan break; 623253440Sgrehan case VTCFG_R_CFGVEC: 624253440Sgrehan value = vs->vs_msix_cfg_idx; 625253440Sgrehan break; 626253440Sgrehan case VTCFG_R_QVEC: 627253440Sgrehan value = vs->vs_curq < vc->vc_nvq ? 628253440Sgrehan vs->vs_queues[vs->vs_curq].vq_msix_idx : 629253440Sgrehan VIRTIO_MSI_NO_VECTOR; 630253440Sgrehan break; 631253440Sgrehan } 632253440Sgrehandone: 633253440Sgrehan if (vs->vs_mtx) 634253440Sgrehan pthread_mutex_unlock(vs->vs_mtx); 635253440Sgrehan return (value); 636253440Sgrehan} 637253440Sgrehan 638253440Sgrehan/* 639253440Sgrehan * Handle pci config space writes. 640253440Sgrehan * If it's to the MSI-X info, do that. 641253440Sgrehan * If it's part of the virtio standard stuff, do that. 642253440Sgrehan * Otherwise dispatch to the actual driver. 643253440Sgrehan */ 644253440Sgrehanvoid 645253440Sgrehanvi_pci_write(struct vmctx *ctx, int vcpu, struct pci_devinst *pi, 646253440Sgrehan int baridx, uint64_t offset, int size, uint64_t value) 647253440Sgrehan{ 648253440Sgrehan struct virtio_softc *vs = pi->pi_arg; 649253440Sgrehan struct vqueue_info *vq; 650253440Sgrehan struct virtio_consts *vc; 651253440Sgrehan struct config_reg *cr; 652253440Sgrehan uint64_t virtio_config_size, max; 653253440Sgrehan const char *name; 654253440Sgrehan uint32_t newoff; 655253440Sgrehan int error; 656253440Sgrehan 657253440Sgrehan if (vs->vs_flags & VIRTIO_USE_MSIX) { 658253440Sgrehan if (baridx == pci_msix_table_bar(pi) || 659253440Sgrehan baridx == pci_msix_pba_bar(pi)) { 660253440Sgrehan pci_emul_msix_twrite(pi, offset, size, value); 661253440Sgrehan return; 662253440Sgrehan } 663253440Sgrehan } 664253440Sgrehan 665253440Sgrehan /* XXX probably should do something better than just assert() */ 666253440Sgrehan assert(baridx == 0); 667253440Sgrehan 668253440Sgrehan if (vs->vs_mtx) 669253440Sgrehan pthread_mutex_lock(vs->vs_mtx); 670253440Sgrehan 671253440Sgrehan vc = vs->vs_vc; 672253440Sgrehan name = vc->vc_name; 673253440Sgrehan 674253440Sgrehan if (size != 1 && size != 2 && size != 4) 675253440Sgrehan goto bad; 676253440Sgrehan 677253440Sgrehan if (pci_msix_enabled(pi)) 678253440Sgrehan virtio_config_size = VTCFG_R_CFG1; 679253440Sgrehan else 680253440Sgrehan virtio_config_size = VTCFG_R_CFG0; 681253440Sgrehan 682253440Sgrehan if (offset >= virtio_config_size) { 683253440Sgrehan /* 684253440Sgrehan * Subtract off the standard size (including MSI-X 685253440Sgrehan * registers if enabled) and dispatch to underlying driver. 686253440Sgrehan */ 687253440Sgrehan newoff = offset - virtio_config_size; 688253440Sgrehan max = vc->vc_cfgsize ? vc->vc_cfgsize : 0x100000000; 689253440Sgrehan if (newoff + size > max) 690253440Sgrehan goto bad; 691253440Sgrehan error = (*vc->vc_cfgwrite)(DEV_SOFTC(vs), newoff, size, value); 692253440Sgrehan if (!error) 693253440Sgrehan goto done; 694253440Sgrehan } 695253440Sgrehan 696253440Sgrehanbad: 697253440Sgrehan cr = vi_find_cr(offset); 698253440Sgrehan if (cr == NULL || cr->cr_size != size || cr->cr_ro) { 699253440Sgrehan if (cr != NULL) { 700253440Sgrehan /* offset must be OK, wrong size and/or reg is R/O */ 701253440Sgrehan if (cr->cr_size != size) 702253440Sgrehan fprintf(stderr, 703253440Sgrehan "%s: write to %s: bad size %d\r\n", 704253440Sgrehan name, cr->cr_name, size); 705253440Sgrehan if (cr->cr_ro) 706253440Sgrehan fprintf(stderr, 707253440Sgrehan "%s: write to read-only reg %s\r\n", 708253440Sgrehan name, cr->cr_name); 709253440Sgrehan } else { 710253440Sgrehan fprintf(stderr, 711253440Sgrehan "%s: write to bad offset/size %jd/%d\r\n", 712253440Sgrehan name, (uintmax_t)offset, size); 713253440Sgrehan } 714253440Sgrehan goto done; 715253440Sgrehan } 716253440Sgrehan 717253440Sgrehan switch (offset) { 718253440Sgrehan case VTCFG_R_GUESTCAP: 719253440Sgrehan vs->vs_negotiated_caps = value & vc->vc_hv_caps; 720271685Sgrehan if (vc->vc_apply_features) 721271685Sgrehan (*vc->vc_apply_features)(DEV_SOFTC(vs), 722271685Sgrehan vs->vs_negotiated_caps); 723253440Sgrehan break; 724253440Sgrehan case VTCFG_R_PFN: 725253440Sgrehan if (vs->vs_curq >= vc->vc_nvq) 726253440Sgrehan goto bad_qindex; 727253440Sgrehan vi_vq_init(vs, value); 728253440Sgrehan break; 729253440Sgrehan case VTCFG_R_QSEL: 730253440Sgrehan /* 731253440Sgrehan * Note that the guest is allowed to select an 732253440Sgrehan * invalid queue; we just need to return a QNUM 733253440Sgrehan * of 0 while the bad queue is selected. 734253440Sgrehan */ 735253440Sgrehan vs->vs_curq = value; 736253440Sgrehan break; 737253440Sgrehan case VTCFG_R_QNOTIFY: 738253440Sgrehan if (value >= vc->vc_nvq) { 739253440Sgrehan fprintf(stderr, "%s: queue %d notify out of range\r\n", 740253440Sgrehan name, (int)value); 741253440Sgrehan goto done; 742253440Sgrehan } 743253440Sgrehan vq = &vs->vs_queues[value]; 744253440Sgrehan if (vq->vq_notify) 745253440Sgrehan (*vq->vq_notify)(DEV_SOFTC(vs), vq); 746253440Sgrehan else if (vc->vc_qnotify) 747253440Sgrehan (*vc->vc_qnotify)(DEV_SOFTC(vs), vq); 748253440Sgrehan else 749253440Sgrehan fprintf(stderr, 750253440Sgrehan "%s: qnotify queue %d: missing vq/vc notify\r\n", 751253440Sgrehan name, (int)value); 752253440Sgrehan break; 753253440Sgrehan case VTCFG_R_STATUS: 754253440Sgrehan vs->vs_status = value; 755253440Sgrehan if (value == 0) 756253440Sgrehan (*vc->vc_reset)(DEV_SOFTC(vs)); 757253440Sgrehan break; 758253440Sgrehan case VTCFG_R_CFGVEC: 759253440Sgrehan vs->vs_msix_cfg_idx = value; 760253440Sgrehan break; 761253440Sgrehan case VTCFG_R_QVEC: 762253440Sgrehan if (vs->vs_curq >= vc->vc_nvq) 763253440Sgrehan goto bad_qindex; 764253440Sgrehan vq = &vs->vs_queues[vs->vs_curq]; 765253440Sgrehan vq->vq_msix_idx = value; 766253440Sgrehan break; 767253440Sgrehan } 768253440Sgrehan goto done; 769253440Sgrehan 770253440Sgrehanbad_qindex: 771253440Sgrehan fprintf(stderr, 772253440Sgrehan "%s: write config reg %s: curq %d >= max %d\r\n", 773253440Sgrehan name, cr->cr_name, vs->vs_curq, vc->vc_nvq); 774253440Sgrehandone: 775253440Sgrehan if (vs->vs_mtx) 776253440Sgrehan pthread_mutex_unlock(vs->vs_mtx); 777253440Sgrehan} 778