blob: 64eb0cd8b8af428ef87eb2db9e0314e5ed9336a9 [file] [log] [blame]
Konrad Rzeszutek Wilk30edc142009-10-13 17:22:20 -04001/*
2 * PCI Backend Operations - respond to PCI requests from Frontend
3 *
4 * Author: Ryan Wilson <hap9@epoch.ncsc.mil>
5 */
Joe Perches283c0972013-06-28 03:21:41 -07006
7#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
8
Konrad Rzeszutek Wilk30edc142009-10-13 17:22:20 -04009#include <linux/module.h>
10#include <linux/wait.h>
11#include <linux/bitops.h>
12#include <xen/events.h>
13#include <linux/sched.h>
14#include "pciback.h"
15
16int verbose_request;
17module_param(verbose_request, int, 0644);
18
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -040019static irqreturn_t xen_pcibk_guest_interrupt(int irq, void *dev_id);
20
Konrad Rzeszutek Wilk0513fe92011-07-19 18:56:39 -040021/* Ensure a device is has the fake IRQ handler "turned on/off" and is
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -040022 * ready to be exported. This MUST be run after xen_pcibk_reset_device
Konrad Rzeszutek Wilk0513fe92011-07-19 18:56:39 -040023 * which does the actual PCI device enable/disable.
24 */
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -040025static void xen_pcibk_control_isr(struct pci_dev *dev, int reset)
Konrad Rzeszutek Wilk0513fe92011-07-19 18:56:39 -040026{
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -040027 struct xen_pcibk_dev_data *dev_data;
Konrad Rzeszutek Wilk0513fe92011-07-19 18:56:39 -040028 int rc;
29 int enable = 0;
30
31 dev_data = pci_get_drvdata(dev);
32 if (!dev_data)
33 return;
34
35 /* We don't deal with bridges */
36 if (dev->hdr_type != PCI_HEADER_TYPE_NORMAL)
37 return;
38
39 if (reset) {
40 dev_data->enable_intx = 0;
41 dev_data->ack_intr = 0;
42 }
43 enable = dev_data->enable_intx;
44
45 /* Asked to disable, but ISR isn't runnig */
46 if (!enable && !dev_data->isr_on)
47 return;
48
49 /* Squirrel away the IRQs in the dev_data. We need this
50 * b/c when device transitions to MSI, the dev->irq is
51 * overwritten with the MSI vector.
52 */
53 if (enable)
54 dev_data->irq = dev->irq;
55
Konrad Rzeszutek Wilke17ab352011-02-16 15:43:25 -050056 /*
57 * SR-IOV devices in all use MSI-X and have no legacy
58 * interrupts, so inhibit creating a fake IRQ handler for them.
59 */
60 if (dev_data->irq == 0)
61 goto out;
62
Konrad Rzeszutek Wilk0513fe92011-07-19 18:56:39 -040063 dev_dbg(&dev->dev, "%s: #%d %s %s%s %s-> %s\n",
64 dev_data->irq_name,
65 dev_data->irq,
66 pci_is_enabled(dev) ? "on" : "off",
67 dev->msi_enabled ? "MSI" : "",
68 dev->msix_enabled ? "MSI/X" : "",
69 dev_data->isr_on ? "enable" : "disable",
70 enable ? "enable" : "disable");
71
72 if (enable) {
73 rc = request_irq(dev_data->irq,
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -040074 xen_pcibk_guest_interrupt, IRQF_SHARED,
Konrad Rzeszutek Wilk0513fe92011-07-19 18:56:39 -040075 dev_data->irq_name, dev);
76 if (rc) {
77 dev_err(&dev->dev, "%s: failed to install fake IRQ " \
78 "handler for IRQ %d! (rc:%d)\n",
79 dev_data->irq_name, dev_data->irq, rc);
80 goto out;
81 }
82 } else {
83 free_irq(dev_data->irq, dev);
84 dev_data->irq = 0;
85 }
86 dev_data->isr_on = enable;
87 dev_data->ack_intr = enable;
88out:
89 dev_dbg(&dev->dev, "%s: #%d %s %s%s %s\n",
90 dev_data->irq_name,
91 dev_data->irq,
92 pci_is_enabled(dev) ? "on" : "off",
93 dev->msi_enabled ? "MSI" : "",
94 dev->msix_enabled ? "MSI/X" : "",
95 enable ? (dev_data->isr_on ? "enabled" : "failed to enable") :
96 (dev_data->isr_on ? "failed to disable" : "disabled"));
97}
98
Konrad Rzeszutek Wilk30edc142009-10-13 17:22:20 -040099/* Ensure a device is "turned off" and ready to be exported.
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -0400100 * (Also see xen_pcibk_config_reset to ensure virtual configuration space is
Konrad Rzeszutek Wilk30edc142009-10-13 17:22:20 -0400101 * ready to be re-exported)
102 */
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -0400103void xen_pcibk_reset_device(struct pci_dev *dev)
Konrad Rzeszutek Wilk30edc142009-10-13 17:22:20 -0400104{
105 u16 cmd;
106
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -0400107 xen_pcibk_control_isr(dev, 1 /* reset device */);
Konrad Rzeszutek Wilk0513fe92011-07-19 18:56:39 -0400108
Konrad Rzeszutek Wilk30edc142009-10-13 17:22:20 -0400109 /* Disable devices (but not bridges) */
110 if (dev->hdr_type == PCI_HEADER_TYPE_NORMAL) {
Konrad Rzeszutek Wilka2be65fd2010-03-03 13:38:43 -0500111#ifdef CONFIG_PCI_MSI
112 /* The guest could have been abruptly killed without
113 * disabling MSI/MSI-X interrupts.*/
114 if (dev->msix_enabled)
115 pci_disable_msix(dev);
116 if (dev->msi_enabled)
117 pci_disable_msi(dev);
118#endif
Konrad Rzeszutek Wilkbdc5c182013-03-05 13:14:19 -0500119 if (pci_is_enabled(dev))
120 pci_disable_device(dev);
Konrad Rzeszutek Wilk30edc142009-10-13 17:22:20 -0400121
122 pci_write_config_word(dev, PCI_COMMAND, 0);
123
124 dev->is_busmaster = 0;
125 } else {
126 pci_read_config_word(dev, PCI_COMMAND, &cmd);
127 if (cmd & (PCI_COMMAND_INVALIDATE)) {
128 cmd &= ~(PCI_COMMAND_INVALIDATE);
129 pci_write_config_word(dev, PCI_COMMAND, cmd);
130
131 dev->is_busmaster = 0;
132 }
133 }
134}
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -0400135
136#ifdef CONFIG_PCI_MSI
137static
138int xen_pcibk_enable_msi(struct xen_pcibk_device *pdev,
139 struct pci_dev *dev, struct xen_pci_op *op)
140{
141 struct xen_pcibk_dev_data *dev_data;
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -0400142 int status;
143
144 if (unlikely(verbose_request))
145 printk(KERN_DEBUG DRV_NAME ": %s: enable MSI\n", pci_name(dev));
146
147 status = pci_enable_msi(dev);
148
149 if (status) {
Joe Perches283c0972013-06-28 03:21:41 -0700150 pr_warn_ratelimited("%s: error enabling MSI for guest %u: err %d\n",
Jan Beulich51ac8892013-02-06 10:30:38 -0500151 pci_name(dev), pdev->xdev->otherend_id,
152 status);
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -0400153 op->value = 0;
154 return XEN_PCI_ERR_op_failed;
155 }
156
157 /* The value the guest needs is actually the IDT vector, not the
158 * the local domain's IRQ number. */
159
160 op->value = dev->irq ? xen_pirq_from_irq(dev->irq) : 0;
161 if (unlikely(verbose_request))
162 printk(KERN_DEBUG DRV_NAME ": %s: MSI: %d\n", pci_name(dev),
163 op->value);
164
165 dev_data = pci_get_drvdata(dev);
166 if (dev_data)
167 dev_data->ack_intr = 0;
168
169 return 0;
170}
171
172static
173int xen_pcibk_disable_msi(struct xen_pcibk_device *pdev,
174 struct pci_dev *dev, struct xen_pci_op *op)
175{
176 struct xen_pcibk_dev_data *dev_data;
177
178 if (unlikely(verbose_request))
179 printk(KERN_DEBUG DRV_NAME ": %s: disable MSI\n",
180 pci_name(dev));
181 pci_disable_msi(dev);
182
183 op->value = dev->irq ? xen_pirq_from_irq(dev->irq) : 0;
184 if (unlikely(verbose_request))
185 printk(KERN_DEBUG DRV_NAME ": %s: MSI: %d\n", pci_name(dev),
186 op->value);
187 dev_data = pci_get_drvdata(dev);
188 if (dev_data)
189 dev_data->ack_intr = 1;
190 return 0;
191}
192
193static
194int xen_pcibk_enable_msix(struct xen_pcibk_device *pdev,
195 struct pci_dev *dev, struct xen_pci_op *op)
196{
197 struct xen_pcibk_dev_data *dev_data;
198 int i, result;
199 struct msix_entry *entries;
200
201 if (unlikely(verbose_request))
202 printk(KERN_DEBUG DRV_NAME ": %s: enable MSI-X\n",
203 pci_name(dev));
204 if (op->value > SH_INFO_MAX_VEC)
205 return -EINVAL;
206
207 entries = kmalloc(op->value * sizeof(*entries), GFP_KERNEL);
208 if (entries == NULL)
209 return -ENOMEM;
210
211 for (i = 0; i < op->value; i++) {
212 entries[i].entry = op->msix_entries[i].entry;
213 entries[i].vector = op->msix_entries[i].vector;
214 }
215
216 result = pci_enable_msix(dev, entries, op->value);
217
218 if (result == 0) {
219 for (i = 0; i < op->value; i++) {
220 op->msix_entries[i].entry = entries[i].entry;
221 if (entries[i].vector)
222 op->msix_entries[i].vector =
223 xen_pirq_from_irq(entries[i].vector);
224 if (unlikely(verbose_request))
225 printk(KERN_DEBUG DRV_NAME ": %s: " \
226 "MSI-X[%d]: %d\n",
227 pci_name(dev), i,
228 op->msix_entries[i].vector);
229 }
Jan Beulich51ac8892013-02-06 10:30:38 -0500230 } else
Joe Perches283c0972013-06-28 03:21:41 -0700231 pr_warn_ratelimited("%s: error enabling MSI-X for guest %u: err %d!\n",
Jan Beulich51ac8892013-02-06 10:30:38 -0500232 pci_name(dev), pdev->xdev->otherend_id,
233 result);
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -0400234 kfree(entries);
235
236 op->value = result;
237 dev_data = pci_get_drvdata(dev);
238 if (dev_data)
239 dev_data->ack_intr = 0;
240
Jan Beulich0ee46ec2012-04-02 15:32:22 +0100241 return result > 0 ? 0 : result;
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -0400242}
243
244static
245int xen_pcibk_disable_msix(struct xen_pcibk_device *pdev,
246 struct pci_dev *dev, struct xen_pci_op *op)
247{
248 struct xen_pcibk_dev_data *dev_data;
249 if (unlikely(verbose_request))
250 printk(KERN_DEBUG DRV_NAME ": %s: disable MSI-X\n",
251 pci_name(dev));
252 pci_disable_msix(dev);
253
254 /*
255 * SR-IOV devices (which don't have any legacy IRQ) have
256 * an undefined IRQ value of zero.
257 */
258 op->value = dev->irq ? xen_pirq_from_irq(dev->irq) : 0;
259 if (unlikely(verbose_request))
260 printk(KERN_DEBUG DRV_NAME ": %s: MSI-X: %d\n", pci_name(dev),
261 op->value);
262 dev_data = pci_get_drvdata(dev);
263 if (dev_data)
264 dev_data->ack_intr = 1;
265 return 0;
266}
267#endif
Konrad Rzeszutek Wilk30edc142009-10-13 17:22:20 -0400268/*
269* Now the same evtchn is used for both pcifront conf_read_write request
270* as well as pcie aer front end ack. We use a new work_queue to schedule
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -0400271* xen_pcibk conf_read_write service for avoiding confict with aer_core
Konrad Rzeszutek Wilk30edc142009-10-13 17:22:20 -0400272* do_recovery job which also use the system default work_queue
273*/
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -0400274void xen_pcibk_test_and_schedule_op(struct xen_pcibk_device *pdev)
Konrad Rzeszutek Wilk30edc142009-10-13 17:22:20 -0400275{
276 /* Check that frontend is requesting an operation and that we are not
277 * already processing a request */
278 if (test_bit(_XEN_PCIF_active, (unsigned long *)&pdev->sh_info->flags)
279 && !test_and_set_bit(_PDEVF_op_active, &pdev->flags)) {
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -0400280 queue_work(xen_pcibk_wq, &pdev->op_work);
Konrad Rzeszutek Wilk30edc142009-10-13 17:22:20 -0400281 }
282 /*_XEN_PCIB_active should have been cleared by pcifront. And also make
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -0400283 sure xen_pcibk is waiting for ack by checking _PCIB_op_pending*/
Konrad Rzeszutek Wilk30edc142009-10-13 17:22:20 -0400284 if (!test_bit(_XEN_PCIB_active, (unsigned long *)&pdev->sh_info->flags)
285 && test_bit(_PCIB_op_pending, &pdev->flags)) {
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -0400286 wake_up(&xen_pcibk_aer_wait_queue);
Konrad Rzeszutek Wilk30edc142009-10-13 17:22:20 -0400287 }
288}
289
290/* Performing the configuration space reads/writes must not be done in atomic
291 * context because some of the pci_* functions can sleep (mostly due to ACPI
292 * use of semaphores). This function is intended to be called from a work
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -0400293 * queue in process context taking a struct xen_pcibk_device as a parameter */
Konrad Rzeszutek Wilk30edc142009-10-13 17:22:20 -0400294
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -0400295void xen_pcibk_do_op(struct work_struct *data)
Konrad Rzeszutek Wilk30edc142009-10-13 17:22:20 -0400296{
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -0400297 struct xen_pcibk_device *pdev =
298 container_of(data, struct xen_pcibk_device, op_work);
Konrad Rzeszutek Wilk30edc142009-10-13 17:22:20 -0400299 struct pci_dev *dev;
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -0400300 struct xen_pcibk_dev_data *dev_data = NULL;
Konrad Rzeszutek Wilk30edc142009-10-13 17:22:20 -0400301 struct xen_pci_op *op = &pdev->sh_info->op;
Konrad Rzeszutek Wilk0513fe92011-07-19 18:56:39 -0400302 int test_intx = 0;
Konrad Rzeszutek Wilk30edc142009-10-13 17:22:20 -0400303
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -0400304 dev = xen_pcibk_get_pci_dev(pdev, op->domain, op->bus, op->devfn);
Konrad Rzeszutek Wilk30edc142009-10-13 17:22:20 -0400305
306 if (dev == NULL)
307 op->err = XEN_PCI_ERR_dev_not_found;
308 else {
Konrad Rzeszutek Wilk0513fe92011-07-19 18:56:39 -0400309 dev_data = pci_get_drvdata(dev);
310 if (dev_data)
311 test_intx = dev_data->enable_intx;
Konrad Rzeszutek Wilk30edc142009-10-13 17:22:20 -0400312 switch (op->cmd) {
313 case XEN_PCI_OP_conf_read:
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -0400314 op->err = xen_pcibk_config_read(dev,
Konrad Rzeszutek Wilk30edc142009-10-13 17:22:20 -0400315 op->offset, op->size, &op->value);
316 break;
317 case XEN_PCI_OP_conf_write:
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -0400318 op->err = xen_pcibk_config_write(dev,
Konrad Rzeszutek Wilk30edc142009-10-13 17:22:20 -0400319 op->offset, op->size, op->value);
320 break;
321#ifdef CONFIG_PCI_MSI
322 case XEN_PCI_OP_enable_msi:
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -0400323 op->err = xen_pcibk_enable_msi(pdev, dev, op);
Konrad Rzeszutek Wilk30edc142009-10-13 17:22:20 -0400324 break;
325 case XEN_PCI_OP_disable_msi:
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -0400326 op->err = xen_pcibk_disable_msi(pdev, dev, op);
Konrad Rzeszutek Wilk30edc142009-10-13 17:22:20 -0400327 break;
328 case XEN_PCI_OP_enable_msix:
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -0400329 op->err = xen_pcibk_enable_msix(pdev, dev, op);
Konrad Rzeszutek Wilk30edc142009-10-13 17:22:20 -0400330 break;
331 case XEN_PCI_OP_disable_msix:
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -0400332 op->err = xen_pcibk_disable_msix(pdev, dev, op);
Konrad Rzeszutek Wilk30edc142009-10-13 17:22:20 -0400333 break;
334#endif
335 default:
336 op->err = XEN_PCI_ERR_not_implemented;
337 break;
338 }
339 }
Konrad Rzeszutek Wilk0513fe92011-07-19 18:56:39 -0400340 if (!op->err && dev && dev_data) {
341 /* Transition detected */
342 if ((dev_data->enable_intx != test_intx))
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -0400343 xen_pcibk_control_isr(dev, 0 /* no reset */);
Konrad Rzeszutek Wilk0513fe92011-07-19 18:56:39 -0400344 }
Konrad Rzeszutek Wilk30edc142009-10-13 17:22:20 -0400345 /* Tell the driver domain that we're done. */
346 wmb();
347 clear_bit(_XEN_PCIF_active, (unsigned long *)&pdev->sh_info->flags);
348 notify_remote_via_irq(pdev->evtchn_irq);
349
350 /* Mark that we're done. */
351 smp_mb__before_clear_bit(); /* /after/ clearing PCIF_active */
352 clear_bit(_PDEVF_op_active, &pdev->flags);
353 smp_mb__after_clear_bit(); /* /before/ final check for work */
354
355 /* Check to see if the driver domain tried to start another request in
356 * between clearing _XEN_PCIF_active and clearing _PDEVF_op_active.
357 */
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -0400358 xen_pcibk_test_and_schedule_op(pdev);
Konrad Rzeszutek Wilk30edc142009-10-13 17:22:20 -0400359}
360
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -0400361irqreturn_t xen_pcibk_handle_event(int irq, void *dev_id)
Konrad Rzeszutek Wilk30edc142009-10-13 17:22:20 -0400362{
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -0400363 struct xen_pcibk_device *pdev = dev_id;
Konrad Rzeszutek Wilk30edc142009-10-13 17:22:20 -0400364
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -0400365 xen_pcibk_test_and_schedule_op(pdev);
Konrad Rzeszutek Wilk30edc142009-10-13 17:22:20 -0400366
367 return IRQ_HANDLED;
368}
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -0400369static irqreturn_t xen_pcibk_guest_interrupt(int irq, void *dev_id)
Konrad Rzeszutek Wilk0513fe92011-07-19 18:56:39 -0400370{
371 struct pci_dev *dev = (struct pci_dev *)dev_id;
Konrad Rzeszutek Wilka92336a2011-07-19 19:40:51 -0400372 struct xen_pcibk_dev_data *dev_data = pci_get_drvdata(dev);
Konrad Rzeszutek Wilk0513fe92011-07-19 18:56:39 -0400373
374 if (dev_data->isr_on && dev_data->ack_intr) {
375 dev_data->handled++;
376 if ((dev_data->handled % 1000) == 0) {
377 if (xen_test_irq_shared(irq)) {
Joe Perches283c0972013-06-28 03:21:41 -0700378 pr_info("%s IRQ line is not shared "
Konrad Rzeszutek Wilk0513fe92011-07-19 18:56:39 -0400379 "with other domains. Turning ISR off\n",
380 dev_data->irq_name);
381 dev_data->ack_intr = 0;
382 }
383 }
384 return IRQ_HANDLED;
385 }
386 return IRQ_NONE;
387}