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  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * PCI Backend - Functions for creating a virtual configuration space for
  4 *               exported PCI Devices.
  5 *               It's dangerous to allow PCI Driver Domains to change their
  6 *               device's resources (memory, i/o ports, interrupts). We need to
  7 *               restrict changes to certain PCI Configuration registers:
  8 *               BARs, INTERRUPT_PIN, most registers in the header...
  9 *
 10 * Author: Ryan Wilson <hap9@epoch.ncsc.mil>
 11 */
 12
 13#define dev_fmt(fmt) DRV_NAME ": " fmt
 14
 15#include <linux/kernel.h>
 16#include <linux/moduleparam.h>
 17#include <linux/pci.h>
 18#include "pciback.h"
 19#include "conf_space.h"
 20#include "conf_space_quirks.h"
 21
 22bool xen_pcibk_permissive;
 23module_param_named(permissive, xen_pcibk_permissive, bool, 0644);
 24
 25/* This is where xen_pcibk_read_config_byte, xen_pcibk_read_config_word,
 26 * xen_pcibk_write_config_word, and xen_pcibk_write_config_byte are created. */
 27#define DEFINE_PCI_CONFIG(op, size, type)			\
 28int xen_pcibk_##op##_config_##size				\
 29(struct pci_dev *dev, int offset, type value, void *data)	\
 30{								\
 31	return pci_##op##_config_##size(dev, offset, value);	\
 32}
 33
 34DEFINE_PCI_CONFIG(read, byte, u8 *)
 35DEFINE_PCI_CONFIG(read, word, u16 *)
 36DEFINE_PCI_CONFIG(read, dword, u32 *)
 37
 38DEFINE_PCI_CONFIG(write, byte, u8)
 39DEFINE_PCI_CONFIG(write, word, u16)
 40DEFINE_PCI_CONFIG(write, dword, u32)
 41
 42static int conf_space_read(struct pci_dev *dev,
 43			   const struct config_field_entry *entry,
 44			   int offset, u32 *value)
 45{
 46	int ret = 0;
 47	const struct config_field *field = entry->field;
 48
 49	*value = 0;
 50
 51	switch (field->size) {
 52	case 1:
 53		if (field->u.b.read)
 54			ret = field->u.b.read(dev, offset, (u8 *) value,
 55					      entry->data);
 56		break;
 57	case 2:
 58		if (field->u.w.read)
 59			ret = field->u.w.read(dev, offset, (u16 *) value,
 60					      entry->data);
 61		break;
 62	case 4:
 63		if (field->u.dw.read)
 64			ret = field->u.dw.read(dev, offset, value, entry->data);
 65		break;
 66	}
 67	return ret;
 68}
 69
 70static int conf_space_write(struct pci_dev *dev,
 71			    const struct config_field_entry *entry,
 72			    int offset, u32 value)
 73{
 74	int ret = 0;
 75	const struct config_field *field = entry->field;
 76
 77	switch (field->size) {
 78	case 1:
 79		if (field->u.b.write)
 80			ret = field->u.b.write(dev, offset, (u8) value,
 81					       entry->data);
 82		break;
 83	case 2:
 84		if (field->u.w.write)
 85			ret = field->u.w.write(dev, offset, (u16) value,
 86					       entry->data);
 87		break;
 88	case 4:
 89		if (field->u.dw.write)
 90			ret = field->u.dw.write(dev, offset, value,
 91						entry->data);
 92		break;
 93	}
 94	return ret;
 95}
 96
 97static inline u32 get_mask(int size)
 98{
 99	if (size == 1)
100		return 0xff;
101	else if (size == 2)
102		return 0xffff;
103	else
104		return 0xffffffff;
105}
106
107static inline int valid_request(int offset, int size)
108{
109	/* Validate request (no un-aligned requests) */
110	if ((size == 1 || size == 2 || size == 4) && (offset % size) == 0)
111		return 1;
112	return 0;
113}
114
115static inline u32 merge_value(u32 val, u32 new_val, u32 new_val_mask,
116			      int offset)
117{
118	if (offset >= 0) {
119		new_val_mask <<= (offset * 8);
120		new_val <<= (offset * 8);
121	} else {
122		new_val_mask >>= (offset * -8);
123		new_val >>= (offset * -8);
124	}
125	val = (val & ~new_val_mask) | (new_val & new_val_mask);
126
127	return val;
128}
129
130static int xen_pcibios_err_to_errno(int err)
131{
132	switch (err) {
133	case PCIBIOS_SUCCESSFUL:
134		return XEN_PCI_ERR_success;
135	case PCIBIOS_DEVICE_NOT_FOUND:
136		return XEN_PCI_ERR_dev_not_found;
137	case PCIBIOS_BAD_REGISTER_NUMBER:
138		return XEN_PCI_ERR_invalid_offset;
139	case PCIBIOS_FUNC_NOT_SUPPORTED:
140		return XEN_PCI_ERR_not_implemented;
141	case PCIBIOS_SET_FAILED:
142		return XEN_PCI_ERR_access_denied;
143	}
144	return err;
145}
146
147int xen_pcibk_config_read(struct pci_dev *dev, int offset, int size,
148			  u32 *ret_val)
149{
150	int err = 0;
151	struct xen_pcibk_dev_data *dev_data = pci_get_drvdata(dev);
152	const struct config_field_entry *cfg_entry;
153	const struct config_field *field;
154	int field_start, field_end;
155	/* if read fails for any reason, return 0
156	 * (as if device didn't respond) */
157	u32 value = 0, tmp_val;
158
159	dev_dbg(&dev->dev, "read %d bytes at 0x%x\n", size, offset);
160
161	if (!valid_request(offset, size)) {
162		err = XEN_PCI_ERR_invalid_offset;
163		goto out;
164	}
165
166	/* Get the real value first, then modify as appropriate */
167	switch (size) {
168	case 1:
169		err = pci_read_config_byte(dev, offset, (u8 *) &value);
170		break;
171	case 2:
172		err = pci_read_config_word(dev, offset, (u16 *) &value);
173		break;
174	case 4:
175		err = pci_read_config_dword(dev, offset, &value);
176		break;
177	}
178
179	list_for_each_entry(cfg_entry, &dev_data->config_fields, list) {
180		field = cfg_entry->field;
181
182		field_start = OFFSET(cfg_entry);
183		field_end = OFFSET(cfg_entry) + field->size;
184
185		if (offset + size > field_start && field_end > offset) {
186			err = conf_space_read(dev, cfg_entry, field_start,
187					      &tmp_val);
188			if (err)
189				goto out;
190
191			value = merge_value(value, tmp_val,
192					    get_mask(field->size),
193					    field_start - offset);
194		}
195	}
196
197out:
198	dev_dbg(&dev->dev, "read %d bytes at 0x%x = %x\n", size, offset, value);
199
200	*ret_val = value;
201	return xen_pcibios_err_to_errno(err);
202}
203
204int xen_pcibk_config_write(struct pci_dev *dev, int offset, int size, u32 value)
205{
206	int err = 0, handled = 0;
207	struct xen_pcibk_dev_data *dev_data = pci_get_drvdata(dev);
208	const struct config_field_entry *cfg_entry;
209	const struct config_field *field;
210	u32 tmp_val;
211	int field_start, field_end;
212
213	dev_dbg(&dev->dev, "write request %d bytes at 0x%x = %x\n",
214		size, offset, value);
215
216	if (!valid_request(offset, size))
217		return XEN_PCI_ERR_invalid_offset;
218
219	list_for_each_entry(cfg_entry, &dev_data->config_fields, list) {
220		field = cfg_entry->field;
221
222		field_start = OFFSET(cfg_entry);
223		field_end = OFFSET(cfg_entry) + field->size;
224
225		if (offset + size > field_start && field_end > offset) {
226			err = conf_space_read(dev, cfg_entry, field_start,
227					      &tmp_val);
228			if (err)
229				break;
230
231			tmp_val = merge_value(tmp_val, value, get_mask(size),
232					      offset - field_start);
233
234			err = conf_space_write(dev, cfg_entry, field_start,
235					       tmp_val);
236
237			/* handled is set true here, but not every byte
238			 * may have been written! Properly detecting if
239			 * every byte is handled is unnecessary as the
240			 * flag is used to detect devices that need
241			 * special helpers to work correctly.
242			 */
243			handled = 1;
244		}
245	}
246
247	if (!handled && !err) {
248		/* By default, anything not specificially handled above is
249		 * read-only. The permissive flag changes this behavior so
250		 * that anything not specifically handled above is writable.
251		 * This means that some fields may still be read-only because
252		 * they have entries in the config_field list that intercept
253		 * the write and do nothing. */
254		if (dev_data->permissive || xen_pcibk_permissive) {
255			switch (size) {
256			case 1:
257				err = pci_write_config_byte(dev, offset,
258							    (u8) value);
259				break;
260			case 2:
261				err = pci_write_config_word(dev, offset,
262							    (u16) value);
263				break;
264			case 4:
265				err = pci_write_config_dword(dev, offset,
266							     (u32) value);
267				break;
268			}
269		} else if (!dev_data->warned_on_write) {
270			dev_data->warned_on_write = 1;
271			dev_warn(&dev->dev, "Driver tried to write to a "
272				 "read-only configuration space field at offset"
273				 " 0x%x, size %d. This may be harmless, but if "
274				 "you have problems with your device:\n"
275				 "1) see permissive attribute in sysfs\n"
276				 "2) report problems to the xen-devel "
277				 "mailing list along with details of your "
278				 "device obtained from lspci.\n", offset, size);
279		}
280	}
281
282	return xen_pcibios_err_to_errno(err);
283}
284
285int xen_pcibk_get_interrupt_type(struct pci_dev *dev)
286{
287	int err;
288	u16 val;
289	int ret = 0;
290
291	/*
292	 * Do not trust dev->msi(x)_enabled here, as enabling could be done
293	 * bypassing the pci_*msi* functions, by the qemu.
294	 */
295	if (dev->msi_cap) {
296		err = pci_read_config_word(dev,
297				dev->msi_cap + PCI_MSI_FLAGS,
298				&val);
299		if (err)
300			return err;
301		if (val & PCI_MSI_FLAGS_ENABLE)
302			ret |= INTERRUPT_TYPE_MSI;
303	}
304	if (dev->msix_cap) {
305		err = pci_read_config_word(dev,
306				dev->msix_cap + PCI_MSIX_FLAGS,
307				&val);
308		if (err)
309			return err;
310		if (val & PCI_MSIX_FLAGS_ENABLE)
311			ret |= INTERRUPT_TYPE_MSIX;
312	}
313
314	/*
315	 * PCIe spec says device cannot use INTx if MSI/MSI-X is enabled,
316	 * so check for INTx only when both are disabled.
317	 */
318	if (!ret) {
319		err = pci_read_config_word(dev, PCI_COMMAND, &val);
320		if (err)
321			return err;
322		if (!(val & PCI_COMMAND_INTX_DISABLE))
323			ret |= INTERRUPT_TYPE_INTX;
324	}
325
326	return ret ?: INTERRUPT_TYPE_NONE;
327}
328
329void xen_pcibk_config_free_dyn_fields(struct pci_dev *dev)
330{
331	struct xen_pcibk_dev_data *dev_data = pci_get_drvdata(dev);
332	struct config_field_entry *cfg_entry, *t;
333	const struct config_field *field;
334
335	dev_dbg(&dev->dev, "free-ing dynamically allocated virtual "
336			   "configuration space fields\n");
337	if (!dev_data)
338		return;
339
340	list_for_each_entry_safe(cfg_entry, t, &dev_data->config_fields, list) {
341		field = cfg_entry->field;
342
343		if (field->clean) {
344			field->clean((struct config_field *)field);
345
346			kfree(cfg_entry->data);
347
348			list_del(&cfg_entry->list);
349			kfree(cfg_entry);
350		}
351
352	}
353}
354
355void xen_pcibk_config_reset_dev(struct pci_dev *dev)
356{
357	struct xen_pcibk_dev_data *dev_data = pci_get_drvdata(dev);
358	const struct config_field_entry *cfg_entry;
359	const struct config_field *field;
360
361	dev_dbg(&dev->dev, "resetting virtual configuration space\n");
362	if (!dev_data)
363		return;
364
365	list_for_each_entry(cfg_entry, &dev_data->config_fields, list) {
366		field = cfg_entry->field;
367
368		if (field->reset)
369			field->reset(dev, OFFSET(cfg_entry), cfg_entry->data);
370	}
371}
372
373void xen_pcibk_config_free_dev(struct pci_dev *dev)
374{
375	struct xen_pcibk_dev_data *dev_data = pci_get_drvdata(dev);
376	struct config_field_entry *cfg_entry, *t;
377	const struct config_field *field;
378
379	dev_dbg(&dev->dev, "free-ing virtual configuration space fields\n");
380	if (!dev_data)
381		return;
382
383	list_for_each_entry_safe(cfg_entry, t, &dev_data->config_fields, list) {
384		list_del(&cfg_entry->list);
385
386		field = cfg_entry->field;
387
388		if (field->release)
389			field->release(dev, OFFSET(cfg_entry), cfg_entry->data);
390
391		kfree(cfg_entry);
392	}
393}
394
395int xen_pcibk_config_add_field_offset(struct pci_dev *dev,
396				    const struct config_field *field,
397				    unsigned int base_offset)
398{
399	int err = 0;
400	struct xen_pcibk_dev_data *dev_data = pci_get_drvdata(dev);
401	struct config_field_entry *cfg_entry;
402	void *tmp;
403
404	cfg_entry = kmalloc(sizeof(*cfg_entry), GFP_KERNEL);
405	if (!cfg_entry) {
406		err = -ENOMEM;
407		goto out;
408	}
409
410	cfg_entry->data = NULL;
411	cfg_entry->field = field;
412	cfg_entry->base_offset = base_offset;
413
414	/* silently ignore duplicate fields */
415	err = xen_pcibk_field_is_dup(dev, OFFSET(cfg_entry));
416	if (err)
417		goto out;
418
419	if (field->init) {
420		tmp = field->init(dev, OFFSET(cfg_entry));
421
422		if (IS_ERR(tmp)) {
423			err = PTR_ERR(tmp);
424			goto out;
425		}
426
427		cfg_entry->data = tmp;
428	}
429
430	dev_dbg(&dev->dev, "added config field at offset 0x%02x\n",
431		OFFSET(cfg_entry));
432	list_add_tail(&cfg_entry->list, &dev_data->config_fields);
433
434out:
435	if (err)
436		kfree(cfg_entry);
437
438	return err;
439}
440
441/* This sets up the device's virtual configuration space to keep track of
442 * certain registers (like the base address registers (BARs) so that we can
443 * keep the client from manipulating them directly.
444 */
445int xen_pcibk_config_init_dev(struct pci_dev *dev)
446{
447	int err = 0;
448	struct xen_pcibk_dev_data *dev_data = pci_get_drvdata(dev);
449
450	dev_dbg(&dev->dev, "initializing virtual configuration space\n");
451
452	INIT_LIST_HEAD(&dev_data->config_fields);
453
454	err = xen_pcibk_config_header_add_fields(dev);
455	if (err)
456		goto out;
457
458	err = xen_pcibk_config_capability_add_fields(dev);
459	if (err)
460		goto out;
461
462	err = xen_pcibk_config_quirks_init(dev);
463
464out:
465	return err;
466}
467
468int xen_pcibk_config_init(void)
469{
470	return xen_pcibk_config_capability_init();
471}
  1/*
  2 * PCI Backend - Functions for creating a virtual configuration space for
  3 *               exported PCI Devices.
  4 *               It's dangerous to allow PCI Driver Domains to change their
  5 *               device's resources (memory, i/o ports, interrupts). We need to
  6 *               restrict changes to certain PCI Configuration registers:
  7 *               BARs, INTERRUPT_PIN, most registers in the header...
  8 *
  9 * Author: Ryan Wilson <hap9@epoch.ncsc.mil>
 10 */
 11
 12#include <linux/kernel.h>
 13#include <linux/moduleparam.h>
 14#include <linux/pci.h>
 15#include "pciback.h"
 16#include "conf_space.h"
 17#include "conf_space_quirks.h"
 18
 19bool xen_pcibk_permissive;
 20module_param_named(permissive, xen_pcibk_permissive, bool, 0644);
 21
 22/* This is where xen_pcibk_read_config_byte, xen_pcibk_read_config_word,
 23 * xen_pcibk_write_config_word, and xen_pcibk_write_config_byte are created. */
 24#define DEFINE_PCI_CONFIG(op, size, type)			\
 25int xen_pcibk_##op##_config_##size				\
 26(struct pci_dev *dev, int offset, type value, void *data)	\
 27{								\
 28	return pci_##op##_config_##size(dev, offset, value);	\
 29}
 30
 31DEFINE_PCI_CONFIG(read, byte, u8 *)
 32DEFINE_PCI_CONFIG(read, word, u16 *)
 33DEFINE_PCI_CONFIG(read, dword, u32 *)
 34
 35DEFINE_PCI_CONFIG(write, byte, u8)
 36DEFINE_PCI_CONFIG(write, word, u16)
 37DEFINE_PCI_CONFIG(write, dword, u32)
 38
 39static int conf_space_read(struct pci_dev *dev,
 40			   const struct config_field_entry *entry,
 41			   int offset, u32 *value)
 42{
 43	int ret = 0;
 44	const struct config_field *field = entry->field;
 45
 46	*value = 0;
 47
 48	switch (field->size) {
 49	case 1:
 50		if (field->u.b.read)
 51			ret = field->u.b.read(dev, offset, (u8 *) value,
 52					      entry->data);
 53		break;
 54	case 2:
 55		if (field->u.w.read)
 56			ret = field->u.w.read(dev, offset, (u16 *) value,
 57					      entry->data);
 58		break;
 59	case 4:
 60		if (field->u.dw.read)
 61			ret = field->u.dw.read(dev, offset, value, entry->data);
 62		break;
 63	}
 64	return ret;
 65}
 66
 67static int conf_space_write(struct pci_dev *dev,
 68			    const struct config_field_entry *entry,
 69			    int offset, u32 value)
 70{
 71	int ret = 0;
 72	const struct config_field *field = entry->field;
 73
 74	switch (field->size) {
 75	case 1:
 76		if (field->u.b.write)
 77			ret = field->u.b.write(dev, offset, (u8) value,
 78					       entry->data);
 79		break;
 80	case 2:
 81		if (field->u.w.write)
 82			ret = field->u.w.write(dev, offset, (u16) value,
 83					       entry->data);
 84		break;
 85	case 4:
 86		if (field->u.dw.write)
 87			ret = field->u.dw.write(dev, offset, value,
 88						entry->data);
 89		break;
 90	}
 91	return ret;
 92}
 93
 94static inline u32 get_mask(int size)
 95{
 96	if (size == 1)
 97		return 0xff;
 98	else if (size == 2)
 99		return 0xffff;
100	else
101		return 0xffffffff;
102}
103
104static inline int valid_request(int offset, int size)
105{
106	/* Validate request (no un-aligned requests) */
107	if ((size == 1 || size == 2 || size == 4) && (offset % size) == 0)
108		return 1;
109	return 0;
110}
111
112static inline u32 merge_value(u32 val, u32 new_val, u32 new_val_mask,
113			      int offset)
114{
115	if (offset >= 0) {
116		new_val_mask <<= (offset * 8);
117		new_val <<= (offset * 8);
118	} else {
119		new_val_mask >>= (offset * -8);
120		new_val >>= (offset * -8);
121	}
122	val = (val & ~new_val_mask) | (new_val & new_val_mask);
123
124	return val;
125}
126
127static int xen_pcibios_err_to_errno(int err)
128{
129	switch (err) {
130	case PCIBIOS_SUCCESSFUL:
131		return XEN_PCI_ERR_success;
132	case PCIBIOS_DEVICE_NOT_FOUND:
133		return XEN_PCI_ERR_dev_not_found;
134	case PCIBIOS_BAD_REGISTER_NUMBER:
135		return XEN_PCI_ERR_invalid_offset;
136	case PCIBIOS_FUNC_NOT_SUPPORTED:
137		return XEN_PCI_ERR_not_implemented;
138	case PCIBIOS_SET_FAILED:
139		return XEN_PCI_ERR_access_denied;
140	}
141	return err;
142}
143
144int xen_pcibk_config_read(struct pci_dev *dev, int offset, int size,
145			  u32 *ret_val)
146{
147	int err = 0;
148	struct xen_pcibk_dev_data *dev_data = pci_get_drvdata(dev);
149	const struct config_field_entry *cfg_entry;
150	const struct config_field *field;
151	int field_start, field_end;
152	/* if read fails for any reason, return 0
153	 * (as if device didn't respond) */
154	u32 value = 0, tmp_val;
155
156	if (unlikely(verbose_request))
157		printk(KERN_DEBUG DRV_NAME ": %s: read %d bytes at 0x%x\n",
158		       pci_name(dev), size, offset);
159
160	if (!valid_request(offset, size)) {
161		err = XEN_PCI_ERR_invalid_offset;
162		goto out;
163	}
164
165	/* Get the real value first, then modify as appropriate */
166	switch (size) {
167	case 1:
168		err = pci_read_config_byte(dev, offset, (u8 *) &value);
169		break;
170	case 2:
171		err = pci_read_config_word(dev, offset, (u16 *) &value);
172		break;
173	case 4:
174		err = pci_read_config_dword(dev, offset, &value);
175		break;
176	}
177
178	list_for_each_entry(cfg_entry, &dev_data->config_fields, list) {
179		field = cfg_entry->field;
180
181		field_start = OFFSET(cfg_entry);
182		field_end = OFFSET(cfg_entry) + field->size;
183
184		if (offset + size > field_start && field_end > offset) {
185			err = conf_space_read(dev, cfg_entry, field_start,
186					      &tmp_val);
187			if (err)
188				goto out;
189
190			value = merge_value(value, tmp_val,
191					    get_mask(field->size),
192					    field_start - offset);
193		}
194	}
195
196out:
197	if (unlikely(verbose_request))
198		printk(KERN_DEBUG DRV_NAME ": %s: read %d bytes at 0x%x = %x\n",
199		       pci_name(dev), size, offset, value);
200
201	*ret_val = value;
202	return xen_pcibios_err_to_errno(err);
203}
204
205int xen_pcibk_config_write(struct pci_dev *dev, int offset, int size, u32 value)
206{
207	int err = 0, handled = 0;
208	struct xen_pcibk_dev_data *dev_data = pci_get_drvdata(dev);
209	const struct config_field_entry *cfg_entry;
210	const struct config_field *field;
211	u32 tmp_val;
212	int field_start, field_end;
213
214	if (unlikely(verbose_request))
215		printk(KERN_DEBUG
216		       DRV_NAME ": %s: write request %d bytes at 0x%x = %x\n",
217		       pci_name(dev), size, offset, value);
218
219	if (!valid_request(offset, size))
220		return XEN_PCI_ERR_invalid_offset;
221
222	list_for_each_entry(cfg_entry, &dev_data->config_fields, list) {
223		field = cfg_entry->field;
224
225		field_start = OFFSET(cfg_entry);
226		field_end = OFFSET(cfg_entry) + field->size;
227
228		if (offset + size > field_start && field_end > offset) {
229			err = conf_space_read(dev, cfg_entry, field_start,
230					      &tmp_val);
231			if (err)
232				break;
233
234			tmp_val = merge_value(tmp_val, value, get_mask(size),
235					      offset - field_start);
236
237			err = conf_space_write(dev, cfg_entry, field_start,
238					       tmp_val);
239
240			/* handled is set true here, but not every byte
241			 * may have been written! Properly detecting if
242			 * every byte is handled is unnecessary as the
243			 * flag is used to detect devices that need
244			 * special helpers to work correctly.
245			 */
246			handled = 1;
247		}
248	}
249
250	if (!handled && !err) {
251		/* By default, anything not specificially handled above is
252		 * read-only. The permissive flag changes this behavior so
253		 * that anything not specifically handled above is writable.
254		 * This means that some fields may still be read-only because
255		 * they have entries in the config_field list that intercept
256		 * the write and do nothing. */
257		if (dev_data->permissive || xen_pcibk_permissive) {
258			switch (size) {
259			case 1:
260				err = pci_write_config_byte(dev, offset,
261							    (u8) value);
262				break;
263			case 2:
264				err = pci_write_config_word(dev, offset,
265							    (u16) value);
266				break;
267			case 4:
268				err = pci_write_config_dword(dev, offset,
269							     (u32) value);
270				break;
271			}
272		} else if (!dev_data->warned_on_write) {
273			dev_data->warned_on_write = 1;
274			dev_warn(&dev->dev, "Driver tried to write to a "
275				 "read-only configuration space field at offset"
276				 " 0x%x, size %d. This may be harmless, but if "
277				 "you have problems with your device:\n"
278				 "1) see permissive attribute in sysfs\n"
279				 "2) report problems to the xen-devel "
280				 "mailing list along with details of your "
281				 "device obtained from lspci.\n", offset, size);
282		}
283	}
284
285	return xen_pcibios_err_to_errno(err);
286}
287
288void xen_pcibk_config_free_dyn_fields(struct pci_dev *dev)
289{
290	struct xen_pcibk_dev_data *dev_data = pci_get_drvdata(dev);
291	struct config_field_entry *cfg_entry, *t;
292	const struct config_field *field;
293
294	dev_dbg(&dev->dev, "free-ing dynamically allocated virtual "
295			   "configuration space fields\n");
296	if (!dev_data)
297		return;
298
299	list_for_each_entry_safe(cfg_entry, t, &dev_data->config_fields, list) {
300		field = cfg_entry->field;
301
302		if (field->clean) {
303			field->clean((struct config_field *)field);
304
305			kfree(cfg_entry->data);
306
307			list_del(&cfg_entry->list);
308			kfree(cfg_entry);
309		}
310
311	}
312}
313
314void xen_pcibk_config_reset_dev(struct pci_dev *dev)
315{
316	struct xen_pcibk_dev_data *dev_data = pci_get_drvdata(dev);
317	const struct config_field_entry *cfg_entry;
318	const struct config_field *field;
319
320	dev_dbg(&dev->dev, "resetting virtual configuration space\n");
321	if (!dev_data)
322		return;
323
324	list_for_each_entry(cfg_entry, &dev_data->config_fields, list) {
325		field = cfg_entry->field;
326
327		if (field->reset)
328			field->reset(dev, OFFSET(cfg_entry), cfg_entry->data);
329	}
330}
331
332void xen_pcibk_config_free_dev(struct pci_dev *dev)
333{
334	struct xen_pcibk_dev_data *dev_data = pci_get_drvdata(dev);
335	struct config_field_entry *cfg_entry, *t;
336	const struct config_field *field;
337
338	dev_dbg(&dev->dev, "free-ing virtual configuration space fields\n");
339	if (!dev_data)
340		return;
341
342	list_for_each_entry_safe(cfg_entry, t, &dev_data->config_fields, list) {
343		list_del(&cfg_entry->list);
344
345		field = cfg_entry->field;
346
347		if (field->release)
348			field->release(dev, OFFSET(cfg_entry), cfg_entry->data);
349
350		kfree(cfg_entry);
351	}
352}
353
354int xen_pcibk_config_add_field_offset(struct pci_dev *dev,
355				    const struct config_field *field,
356				    unsigned int base_offset)
357{
358	int err = 0;
359	struct xen_pcibk_dev_data *dev_data = pci_get_drvdata(dev);
360	struct config_field_entry *cfg_entry;
361	void *tmp;
362
363	cfg_entry = kmalloc(sizeof(*cfg_entry), GFP_KERNEL);
364	if (!cfg_entry) {
365		err = -ENOMEM;
366		goto out;
367	}
368
369	cfg_entry->data = NULL;
370	cfg_entry->field = field;
371	cfg_entry->base_offset = base_offset;
372
373	/* silently ignore duplicate fields */
374	err = xen_pcibk_field_is_dup(dev, OFFSET(cfg_entry));
375	if (err)
376		goto out;
377
378	if (field->init) {
379		tmp = field->init(dev, OFFSET(cfg_entry));
380
381		if (IS_ERR(tmp)) {
382			err = PTR_ERR(tmp);
383			goto out;
384		}
385
386		cfg_entry->data = tmp;
387	}
388
389	dev_dbg(&dev->dev, "added config field at offset 0x%02x\n",
390		OFFSET(cfg_entry));
391	list_add_tail(&cfg_entry->list, &dev_data->config_fields);
392
393out:
394	if (err)
395		kfree(cfg_entry);
396
397	return err;
398}
399
400/* This sets up the device's virtual configuration space to keep track of
401 * certain registers (like the base address registers (BARs) so that we can
402 * keep the client from manipulating them directly.
403 */
404int xen_pcibk_config_init_dev(struct pci_dev *dev)
405{
406	int err = 0;
407	struct xen_pcibk_dev_data *dev_data = pci_get_drvdata(dev);
408
409	dev_dbg(&dev->dev, "initializing virtual configuration space\n");
410
411	INIT_LIST_HEAD(&dev_data->config_fields);
412
413	err = xen_pcibk_config_header_add_fields(dev);
414	if (err)
415		goto out;
416
417	err = xen_pcibk_config_capability_add_fields(dev);
418	if (err)
419		goto out;
420
421	err = xen_pcibk_config_quirks_init(dev);
422
423out:
424	return err;
425}
426
427int xen_pcibk_config_init(void)
428{
429	return xen_pcibk_config_capability_init();
430}