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v3.5.6
  1#include <linux/delay.h>
  2#include <linux/pci.h>
  3#include <linux/module.h>
  4#include <linux/sched.h>
  5#include <linux/slab.h>
  6#include <linux/ioport.h>
  7#include <linux/wait.h>
  8
  9#include "pci.h"
 10
 11/*
 12 * This interrupt-safe spinlock protects all accesses to PCI
 13 * configuration space.
 14 */
 15
 16DEFINE_RAW_SPINLOCK(pci_lock);
 17
 18/*
 19 *  Wrappers for all PCI configuration access functions.  They just check
 20 *  alignment, do locking and call the low-level functions pointed to
 21 *  by pci_dev->ops.
 22 */
 23
 24#define PCI_byte_BAD 0
 25#define PCI_word_BAD (pos & 1)
 26#define PCI_dword_BAD (pos & 3)
 27
 28#define PCI_OP_READ(size,type,len) \
 29int pci_bus_read_config_##size \
 30	(struct pci_bus *bus, unsigned int devfn, int pos, type *value)	\
 31{									\
 32	int res;							\
 33	unsigned long flags;						\
 34	u32 data = 0;							\
 35	if (PCI_##size##_BAD) return PCIBIOS_BAD_REGISTER_NUMBER;	\
 36	raw_spin_lock_irqsave(&pci_lock, flags);			\
 37	res = bus->ops->read(bus, devfn, pos, len, &data);		\
 38	*value = (type)data;						\
 39	raw_spin_unlock_irqrestore(&pci_lock, flags);		\
 40	return res;							\
 41}
 42
 43#define PCI_OP_WRITE(size,type,len) \
 44int pci_bus_write_config_##size \
 45	(struct pci_bus *bus, unsigned int devfn, int pos, type value)	\
 46{									\
 47	int res;							\
 48	unsigned long flags;						\
 49	if (PCI_##size##_BAD) return PCIBIOS_BAD_REGISTER_NUMBER;	\
 50	raw_spin_lock_irqsave(&pci_lock, flags);			\
 51	res = bus->ops->write(bus, devfn, pos, len, value);		\
 52	raw_spin_unlock_irqrestore(&pci_lock, flags);		\
 53	return res;							\
 54}
 55
 56PCI_OP_READ(byte, u8, 1)
 57PCI_OP_READ(word, u16, 2)
 58PCI_OP_READ(dword, u32, 4)
 59PCI_OP_WRITE(byte, u8, 1)
 60PCI_OP_WRITE(word, u16, 2)
 61PCI_OP_WRITE(dword, u32, 4)
 62
 63EXPORT_SYMBOL(pci_bus_read_config_byte);
 64EXPORT_SYMBOL(pci_bus_read_config_word);
 65EXPORT_SYMBOL(pci_bus_read_config_dword);
 66EXPORT_SYMBOL(pci_bus_write_config_byte);
 67EXPORT_SYMBOL(pci_bus_write_config_word);
 68EXPORT_SYMBOL(pci_bus_write_config_dword);
 69
 70/**
 71 * pci_bus_set_ops - Set raw operations of pci bus
 72 * @bus:	pci bus struct
 73 * @ops:	new raw operations
 74 *
 75 * Return previous raw operations
 76 */
 77struct pci_ops *pci_bus_set_ops(struct pci_bus *bus, struct pci_ops *ops)
 78{
 79	struct pci_ops *old_ops;
 80	unsigned long flags;
 81
 82	raw_spin_lock_irqsave(&pci_lock, flags);
 83	old_ops = bus->ops;
 84	bus->ops = ops;
 85	raw_spin_unlock_irqrestore(&pci_lock, flags);
 86	return old_ops;
 87}
 88EXPORT_SYMBOL(pci_bus_set_ops);
 89
 90/**
 91 * pci_read_vpd - Read one entry from Vital Product Data
 92 * @dev:	pci device struct
 93 * @pos:	offset in vpd space
 94 * @count:	number of bytes to read
 95 * @buf:	pointer to where to store result
 96 *
 97 */
 98ssize_t pci_read_vpd(struct pci_dev *dev, loff_t pos, size_t count, void *buf)
 99{
100	if (!dev->vpd || !dev->vpd->ops)
101		return -ENODEV;
102	return dev->vpd->ops->read(dev, pos, count, buf);
103}
104EXPORT_SYMBOL(pci_read_vpd);
105
106/**
107 * pci_write_vpd - Write entry to Vital Product Data
108 * @dev:	pci device struct
109 * @pos:	offset in vpd space
110 * @count:	number of bytes to write
111 * @buf:	buffer containing write data
112 *
113 */
114ssize_t pci_write_vpd(struct pci_dev *dev, loff_t pos, size_t count, const void *buf)
115{
116	if (!dev->vpd || !dev->vpd->ops)
117		return -ENODEV;
118	return dev->vpd->ops->write(dev, pos, count, buf);
119}
120EXPORT_SYMBOL(pci_write_vpd);
121
122/*
123 * The following routines are to prevent the user from accessing PCI config
124 * space when it's unsafe to do so.  Some devices require this during BIST and
125 * we're required to prevent it during D-state transitions.
126 *
127 * We have a bit per device to indicate it's blocked and a global wait queue
128 * for callers to sleep on until devices are unblocked.
129 */
130static DECLARE_WAIT_QUEUE_HEAD(pci_cfg_wait);
131
132static noinline void pci_wait_cfg(struct pci_dev *dev)
133{
134	DECLARE_WAITQUEUE(wait, current);
135
136	__add_wait_queue(&pci_cfg_wait, &wait);
137	do {
138		set_current_state(TASK_UNINTERRUPTIBLE);
139		raw_spin_unlock_irq(&pci_lock);
140		schedule();
141		raw_spin_lock_irq(&pci_lock);
142	} while (dev->block_cfg_access);
143	__remove_wait_queue(&pci_cfg_wait, &wait);
144}
145
146/* Returns 0 on success, negative values indicate error. */
147#define PCI_USER_READ_CONFIG(size,type)					\
148int pci_user_read_config_##size						\
149	(struct pci_dev *dev, int pos, type *val)			\
150{									\
151	int ret = 0;							\
152	u32 data = -1;							\
153	if (PCI_##size##_BAD)						\
154		return -EINVAL;						\
155	raw_spin_lock_irq(&pci_lock);				\
156	if (unlikely(dev->block_cfg_access))				\
157		pci_wait_cfg(dev);					\
158	ret = dev->bus->ops->read(dev->bus, dev->devfn,			\
159					pos, sizeof(type), &data);	\
160	raw_spin_unlock_irq(&pci_lock);				\
161	*val = (type)data;						\
162	if (ret > 0)							\
163		ret = -EINVAL;						\
164	return ret;							\
165}
166
167/* Returns 0 on success, negative values indicate error. */
168#define PCI_USER_WRITE_CONFIG(size,type)				\
169int pci_user_write_config_##size					\
170	(struct pci_dev *dev, int pos, type val)			\
171{									\
172	int ret = -EIO;							\
173	if (PCI_##size##_BAD)						\
174		return -EINVAL;						\
175	raw_spin_lock_irq(&pci_lock);				\
176	if (unlikely(dev->block_cfg_access))				\
177		pci_wait_cfg(dev);					\
178	ret = dev->bus->ops->write(dev->bus, dev->devfn,		\
179					pos, sizeof(type), val);	\
180	raw_spin_unlock_irq(&pci_lock);				\
181	if (ret > 0)							\
182		ret = -EINVAL;						\
183	return ret;							\
184}
185
186PCI_USER_READ_CONFIG(byte, u8)
187PCI_USER_READ_CONFIG(word, u16)
188PCI_USER_READ_CONFIG(dword, u32)
189PCI_USER_WRITE_CONFIG(byte, u8)
190PCI_USER_WRITE_CONFIG(word, u16)
191PCI_USER_WRITE_CONFIG(dword, u32)
192
193/* VPD access through PCI 2.2+ VPD capability */
194
195#define PCI_VPD_PCI22_SIZE (PCI_VPD_ADDR_MASK + 1)
196
197struct pci_vpd_pci22 {
198	struct pci_vpd base;
199	struct mutex lock;
200	u16	flag;
201	bool	busy;
202	u8	cap;
203};
204
205/*
206 * Wait for last operation to complete.
207 * This code has to spin since there is no other notification from the PCI
208 * hardware. Since the VPD is often implemented by serial attachment to an
209 * EEPROM, it may take many milliseconds to complete.
210 *
211 * Returns 0 on success, negative values indicate error.
212 */
213static int pci_vpd_pci22_wait(struct pci_dev *dev)
214{
215	struct pci_vpd_pci22 *vpd =
216		container_of(dev->vpd, struct pci_vpd_pci22, base);
217	unsigned long timeout = jiffies + HZ/20 + 2;
218	u16 status;
219	int ret;
220
221	if (!vpd->busy)
222		return 0;
223
224	for (;;) {
225		ret = pci_user_read_config_word(dev, vpd->cap + PCI_VPD_ADDR,
226						&status);
227		if (ret < 0)
228			return ret;
229
230		if ((status & PCI_VPD_ADDR_F) == vpd->flag) {
231			vpd->busy = false;
232			return 0;
233		}
234
235		if (time_after(jiffies, timeout)) {
236			dev_printk(KERN_DEBUG, &dev->dev,
237				   "vpd r/w failed.  This is likely a firmware "
238				   "bug on this device.  Contact the card "
239				   "vendor for a firmware update.");
240			return -ETIMEDOUT;
241		}
242		if (fatal_signal_pending(current))
243			return -EINTR;
244		if (!cond_resched())
245			udelay(10);
246	}
247}
248
249static ssize_t pci_vpd_pci22_read(struct pci_dev *dev, loff_t pos, size_t count,
250				  void *arg)
251{
252	struct pci_vpd_pci22 *vpd =
253		container_of(dev->vpd, struct pci_vpd_pci22, base);
254	int ret;
255	loff_t end = pos + count;
256	u8 *buf = arg;
257
258	if (pos < 0 || pos > vpd->base.len || end > vpd->base.len)
259		return -EINVAL;
260
261	if (mutex_lock_killable(&vpd->lock))
262		return -EINTR;
263
264	ret = pci_vpd_pci22_wait(dev);
265	if (ret < 0)
266		goto out;
267
268	while (pos < end) {
269		u32 val;
270		unsigned int i, skip;
271
272		ret = pci_user_write_config_word(dev, vpd->cap + PCI_VPD_ADDR,
273						 pos & ~3);
274		if (ret < 0)
275			break;
276		vpd->busy = true;
277		vpd->flag = PCI_VPD_ADDR_F;
278		ret = pci_vpd_pci22_wait(dev);
279		if (ret < 0)
280			break;
281
282		ret = pci_user_read_config_dword(dev, vpd->cap + PCI_VPD_DATA, &val);
283		if (ret < 0)
284			break;
285
286		skip = pos & 3;
287		for (i = 0;  i < sizeof(u32); i++) {
288			if (i >= skip) {
289				*buf++ = val;
290				if (++pos == end)
291					break;
292			}
293			val >>= 8;
294		}
295	}
296out:
297	mutex_unlock(&vpd->lock);
298	return ret ? ret : count;
299}
300
301static ssize_t pci_vpd_pci22_write(struct pci_dev *dev, loff_t pos, size_t count,
302				   const void *arg)
303{
304	struct pci_vpd_pci22 *vpd =
305		container_of(dev->vpd, struct pci_vpd_pci22, base);
306	const u8 *buf = arg;
307	loff_t end = pos + count;
308	int ret = 0;
309
310	if (pos < 0 || (pos & 3) || (count & 3) || end > vpd->base.len)
311		return -EINVAL;
312
313	if (mutex_lock_killable(&vpd->lock))
314		return -EINTR;
315
316	ret = pci_vpd_pci22_wait(dev);
317	if (ret < 0)
318		goto out;
319
320	while (pos < end) {
321		u32 val;
322
323		val = *buf++;
324		val |= *buf++ << 8;
325		val |= *buf++ << 16;
326		val |= *buf++ << 24;
327
328		ret = pci_user_write_config_dword(dev, vpd->cap + PCI_VPD_DATA, val);
329		if (ret < 0)
330			break;
331		ret = pci_user_write_config_word(dev, vpd->cap + PCI_VPD_ADDR,
332						 pos | PCI_VPD_ADDR_F);
333		if (ret < 0)
334			break;
335
336		vpd->busy = true;
337		vpd->flag = 0;
338		ret = pci_vpd_pci22_wait(dev);
339		if (ret < 0)
340			break;
341
342		pos += sizeof(u32);
343	}
344out:
345	mutex_unlock(&vpd->lock);
346	return ret ? ret : count;
347}
348
349static void pci_vpd_pci22_release(struct pci_dev *dev)
350{
351	kfree(container_of(dev->vpd, struct pci_vpd_pci22, base));
352}
353
354static const struct pci_vpd_ops pci_vpd_pci22_ops = {
355	.read = pci_vpd_pci22_read,
356	.write = pci_vpd_pci22_write,
357	.release = pci_vpd_pci22_release,
358};
359
360int pci_vpd_pci22_init(struct pci_dev *dev)
361{
362	struct pci_vpd_pci22 *vpd;
363	u8 cap;
364
365	cap = pci_find_capability(dev, PCI_CAP_ID_VPD);
366	if (!cap)
367		return -ENODEV;
368	vpd = kzalloc(sizeof(*vpd), GFP_ATOMIC);
369	if (!vpd)
370		return -ENOMEM;
371
372	vpd->base.len = PCI_VPD_PCI22_SIZE;
373	vpd->base.ops = &pci_vpd_pci22_ops;
374	mutex_init(&vpd->lock);
375	vpd->cap = cap;
376	vpd->busy = false;
377	dev->vpd = &vpd->base;
378	return 0;
379}
380
381/**
382 * pci_vpd_truncate - Set available Vital Product Data size
383 * @dev:	pci device struct
384 * @size:	available memory in bytes
385 *
386 * Adjust size of available VPD area.
387 */
388int pci_vpd_truncate(struct pci_dev *dev, size_t size)
389{
390	if (!dev->vpd)
391		return -EINVAL;
392
393	/* limited by the access method */
394	if (size > dev->vpd->len)
395		return -EINVAL;
396
397	dev->vpd->len = size;
398	if (dev->vpd->attr)
399		dev->vpd->attr->size = size;
400
401	return 0;
402}
403EXPORT_SYMBOL(pci_vpd_truncate);
404
405/**
406 * pci_cfg_access_lock - Lock PCI config reads/writes
407 * @dev:	pci device struct
408 *
409 * When access is locked, any userspace reads or writes to config
410 * space and concurrent lock requests will sleep until access is
411 * allowed via pci_cfg_access_unlocked again.
412 */
413void pci_cfg_access_lock(struct pci_dev *dev)
414{
415	might_sleep();
416
417	raw_spin_lock_irq(&pci_lock);
418	if (dev->block_cfg_access)
419		pci_wait_cfg(dev);
420	dev->block_cfg_access = 1;
421	raw_spin_unlock_irq(&pci_lock);
422}
423EXPORT_SYMBOL_GPL(pci_cfg_access_lock);
424
425/**
426 * pci_cfg_access_trylock - try to lock PCI config reads/writes
427 * @dev:	pci device struct
428 *
429 * Same as pci_cfg_access_lock, but will return 0 if access is
430 * already locked, 1 otherwise. This function can be used from
431 * atomic contexts.
432 */
433bool pci_cfg_access_trylock(struct pci_dev *dev)
434{
435	unsigned long flags;
436	bool locked = true;
437
438	raw_spin_lock_irqsave(&pci_lock, flags);
439	if (dev->block_cfg_access)
440		locked = false;
441	else
442		dev->block_cfg_access = 1;
443	raw_spin_unlock_irqrestore(&pci_lock, flags);
444
445	return locked;
 
 
446}
447EXPORT_SYMBOL_GPL(pci_cfg_access_trylock);
448
449/**
450 * pci_cfg_access_unlock - Unlock PCI config reads/writes
451 * @dev:	pci device struct
452 *
453 * This function allows PCI config accesses to resume.
454 */
455void pci_cfg_access_unlock(struct pci_dev *dev)
456{
457	unsigned long flags;
458
459	raw_spin_lock_irqsave(&pci_lock, flags);
460
461	/* This indicates a problem in the caller, but we don't need
462	 * to kill them, unlike a double-block above. */
463	WARN_ON(!dev->block_cfg_access);
464
465	dev->block_cfg_access = 0;
466	wake_up_all(&pci_cfg_wait);
467	raw_spin_unlock_irqrestore(&pci_lock, flags);
468}
469EXPORT_SYMBOL_GPL(pci_cfg_access_unlock);
v3.1
  1#include <linux/delay.h>
  2#include <linux/pci.h>
  3#include <linux/module.h>
  4#include <linux/sched.h>
  5#include <linux/slab.h>
  6#include <linux/ioport.h>
  7#include <linux/wait.h>
  8
  9#include "pci.h"
 10
 11/*
 12 * This interrupt-safe spinlock protects all accesses to PCI
 13 * configuration space.
 14 */
 15
 16static DEFINE_RAW_SPINLOCK(pci_lock);
 17
 18/*
 19 *  Wrappers for all PCI configuration access functions.  They just check
 20 *  alignment, do locking and call the low-level functions pointed to
 21 *  by pci_dev->ops.
 22 */
 23
 24#define PCI_byte_BAD 0
 25#define PCI_word_BAD (pos & 1)
 26#define PCI_dword_BAD (pos & 3)
 27
 28#define PCI_OP_READ(size,type,len) \
 29int pci_bus_read_config_##size \
 30	(struct pci_bus *bus, unsigned int devfn, int pos, type *value)	\
 31{									\
 32	int res;							\
 33	unsigned long flags;						\
 34	u32 data = 0;							\
 35	if (PCI_##size##_BAD) return PCIBIOS_BAD_REGISTER_NUMBER;	\
 36	raw_spin_lock_irqsave(&pci_lock, flags);			\
 37	res = bus->ops->read(bus, devfn, pos, len, &data);		\
 38	*value = (type)data;						\
 39	raw_spin_unlock_irqrestore(&pci_lock, flags);		\
 40	return res;							\
 41}
 42
 43#define PCI_OP_WRITE(size,type,len) \
 44int pci_bus_write_config_##size \
 45	(struct pci_bus *bus, unsigned int devfn, int pos, type value)	\
 46{									\
 47	int res;							\
 48	unsigned long flags;						\
 49	if (PCI_##size##_BAD) return PCIBIOS_BAD_REGISTER_NUMBER;	\
 50	raw_spin_lock_irqsave(&pci_lock, flags);			\
 51	res = bus->ops->write(bus, devfn, pos, len, value);		\
 52	raw_spin_unlock_irqrestore(&pci_lock, flags);		\
 53	return res;							\
 54}
 55
 56PCI_OP_READ(byte, u8, 1)
 57PCI_OP_READ(word, u16, 2)
 58PCI_OP_READ(dword, u32, 4)
 59PCI_OP_WRITE(byte, u8, 1)
 60PCI_OP_WRITE(word, u16, 2)
 61PCI_OP_WRITE(dword, u32, 4)
 62
 63EXPORT_SYMBOL(pci_bus_read_config_byte);
 64EXPORT_SYMBOL(pci_bus_read_config_word);
 65EXPORT_SYMBOL(pci_bus_read_config_dword);
 66EXPORT_SYMBOL(pci_bus_write_config_byte);
 67EXPORT_SYMBOL(pci_bus_write_config_word);
 68EXPORT_SYMBOL(pci_bus_write_config_dword);
 69
 70/**
 71 * pci_bus_set_ops - Set raw operations of pci bus
 72 * @bus:	pci bus struct
 73 * @ops:	new raw operations
 74 *
 75 * Return previous raw operations
 76 */
 77struct pci_ops *pci_bus_set_ops(struct pci_bus *bus, struct pci_ops *ops)
 78{
 79	struct pci_ops *old_ops;
 80	unsigned long flags;
 81
 82	raw_spin_lock_irqsave(&pci_lock, flags);
 83	old_ops = bus->ops;
 84	bus->ops = ops;
 85	raw_spin_unlock_irqrestore(&pci_lock, flags);
 86	return old_ops;
 87}
 88EXPORT_SYMBOL(pci_bus_set_ops);
 89
 90/**
 91 * pci_read_vpd - Read one entry from Vital Product Data
 92 * @dev:	pci device struct
 93 * @pos:	offset in vpd space
 94 * @count:	number of bytes to read
 95 * @buf:	pointer to where to store result
 96 *
 97 */
 98ssize_t pci_read_vpd(struct pci_dev *dev, loff_t pos, size_t count, void *buf)
 99{
100	if (!dev->vpd || !dev->vpd->ops)
101		return -ENODEV;
102	return dev->vpd->ops->read(dev, pos, count, buf);
103}
104EXPORT_SYMBOL(pci_read_vpd);
105
106/**
107 * pci_write_vpd - Write entry to Vital Product Data
108 * @dev:	pci device struct
109 * @pos:	offset in vpd space
110 * @count:	number of bytes to write
111 * @buf:	buffer containing write data
112 *
113 */
114ssize_t pci_write_vpd(struct pci_dev *dev, loff_t pos, size_t count, const void *buf)
115{
116	if (!dev->vpd || !dev->vpd->ops)
117		return -ENODEV;
118	return dev->vpd->ops->write(dev, pos, count, buf);
119}
120EXPORT_SYMBOL(pci_write_vpd);
121
122/*
123 * The following routines are to prevent the user from accessing PCI config
124 * space when it's unsafe to do so.  Some devices require this during BIST and
125 * we're required to prevent it during D-state transitions.
126 *
127 * We have a bit per device to indicate it's blocked and a global wait queue
128 * for callers to sleep on until devices are unblocked.
129 */
130static DECLARE_WAIT_QUEUE_HEAD(pci_ucfg_wait);
131
132static noinline void pci_wait_ucfg(struct pci_dev *dev)
133{
134	DECLARE_WAITQUEUE(wait, current);
135
136	__add_wait_queue(&pci_ucfg_wait, &wait);
137	do {
138		set_current_state(TASK_UNINTERRUPTIBLE);
139		raw_spin_unlock_irq(&pci_lock);
140		schedule();
141		raw_spin_lock_irq(&pci_lock);
142	} while (dev->block_ucfg_access);
143	__remove_wait_queue(&pci_ucfg_wait, &wait);
144}
145
146/* Returns 0 on success, negative values indicate error. */
147#define PCI_USER_READ_CONFIG(size,type)					\
148int pci_user_read_config_##size						\
149	(struct pci_dev *dev, int pos, type *val)			\
150{									\
151	int ret = 0;							\
152	u32 data = -1;							\
153	if (PCI_##size##_BAD)						\
154		return -EINVAL;						\
155	raw_spin_lock_irq(&pci_lock);				\
156	if (unlikely(dev->block_ucfg_access)) pci_wait_ucfg(dev);	\
 
157	ret = dev->bus->ops->read(dev->bus, dev->devfn,			\
158					pos, sizeof(type), &data);	\
159	raw_spin_unlock_irq(&pci_lock);				\
160	*val = (type)data;						\
161	if (ret > 0)							\
162		ret = -EINVAL;						\
163	return ret;							\
164}
165
166/* Returns 0 on success, negative values indicate error. */
167#define PCI_USER_WRITE_CONFIG(size,type)				\
168int pci_user_write_config_##size					\
169	(struct pci_dev *dev, int pos, type val)			\
170{									\
171	int ret = -EIO;							\
172	if (PCI_##size##_BAD)						\
173		return -EINVAL;						\
174	raw_spin_lock_irq(&pci_lock);				\
175	if (unlikely(dev->block_ucfg_access)) pci_wait_ucfg(dev);	\
 
176	ret = dev->bus->ops->write(dev->bus, dev->devfn,		\
177					pos, sizeof(type), val);	\
178	raw_spin_unlock_irq(&pci_lock);				\
179	if (ret > 0)							\
180		ret = -EINVAL;						\
181	return ret;							\
182}
183
184PCI_USER_READ_CONFIG(byte, u8)
185PCI_USER_READ_CONFIG(word, u16)
186PCI_USER_READ_CONFIG(dword, u32)
187PCI_USER_WRITE_CONFIG(byte, u8)
188PCI_USER_WRITE_CONFIG(word, u16)
189PCI_USER_WRITE_CONFIG(dword, u32)
190
191/* VPD access through PCI 2.2+ VPD capability */
192
193#define PCI_VPD_PCI22_SIZE (PCI_VPD_ADDR_MASK + 1)
194
195struct pci_vpd_pci22 {
196	struct pci_vpd base;
197	struct mutex lock;
198	u16	flag;
199	bool	busy;
200	u8	cap;
201};
202
203/*
204 * Wait for last operation to complete.
205 * This code has to spin since there is no other notification from the PCI
206 * hardware. Since the VPD is often implemented by serial attachment to an
207 * EEPROM, it may take many milliseconds to complete.
208 *
209 * Returns 0 on success, negative values indicate error.
210 */
211static int pci_vpd_pci22_wait(struct pci_dev *dev)
212{
213	struct pci_vpd_pci22 *vpd =
214		container_of(dev->vpd, struct pci_vpd_pci22, base);
215	unsigned long timeout = jiffies + HZ/20 + 2;
216	u16 status;
217	int ret;
218
219	if (!vpd->busy)
220		return 0;
221
222	for (;;) {
223		ret = pci_user_read_config_word(dev, vpd->cap + PCI_VPD_ADDR,
224						&status);
225		if (ret < 0)
226			return ret;
227
228		if ((status & PCI_VPD_ADDR_F) == vpd->flag) {
229			vpd->busy = false;
230			return 0;
231		}
232
233		if (time_after(jiffies, timeout)) {
234			dev_printk(KERN_DEBUG, &dev->dev,
235				   "vpd r/w failed.  This is likely a firmware "
236				   "bug on this device.  Contact the card "
237				   "vendor for a firmware update.");
238			return -ETIMEDOUT;
239		}
240		if (fatal_signal_pending(current))
241			return -EINTR;
242		if (!cond_resched())
243			udelay(10);
244	}
245}
246
247static ssize_t pci_vpd_pci22_read(struct pci_dev *dev, loff_t pos, size_t count,
248				  void *arg)
249{
250	struct pci_vpd_pci22 *vpd =
251		container_of(dev->vpd, struct pci_vpd_pci22, base);
252	int ret;
253	loff_t end = pos + count;
254	u8 *buf = arg;
255
256	if (pos < 0 || pos > vpd->base.len || end > vpd->base.len)
257		return -EINVAL;
258
259	if (mutex_lock_killable(&vpd->lock))
260		return -EINTR;
261
262	ret = pci_vpd_pci22_wait(dev);
263	if (ret < 0)
264		goto out;
265
266	while (pos < end) {
267		u32 val;
268		unsigned int i, skip;
269
270		ret = pci_user_write_config_word(dev, vpd->cap + PCI_VPD_ADDR,
271						 pos & ~3);
272		if (ret < 0)
273			break;
274		vpd->busy = true;
275		vpd->flag = PCI_VPD_ADDR_F;
276		ret = pci_vpd_pci22_wait(dev);
277		if (ret < 0)
278			break;
279
280		ret = pci_user_read_config_dword(dev, vpd->cap + PCI_VPD_DATA, &val);
281		if (ret < 0)
282			break;
283
284		skip = pos & 3;
285		for (i = 0;  i < sizeof(u32); i++) {
286			if (i >= skip) {
287				*buf++ = val;
288				if (++pos == end)
289					break;
290			}
291			val >>= 8;
292		}
293	}
294out:
295	mutex_unlock(&vpd->lock);
296	return ret ? ret : count;
297}
298
299static ssize_t pci_vpd_pci22_write(struct pci_dev *dev, loff_t pos, size_t count,
300				   const void *arg)
301{
302	struct pci_vpd_pci22 *vpd =
303		container_of(dev->vpd, struct pci_vpd_pci22, base);
304	const u8 *buf = arg;
305	loff_t end = pos + count;
306	int ret = 0;
307
308	if (pos < 0 || (pos & 3) || (count & 3) || end > vpd->base.len)
309		return -EINVAL;
310
311	if (mutex_lock_killable(&vpd->lock))
312		return -EINTR;
313
314	ret = pci_vpd_pci22_wait(dev);
315	if (ret < 0)
316		goto out;
317
318	while (pos < end) {
319		u32 val;
320
321		val = *buf++;
322		val |= *buf++ << 8;
323		val |= *buf++ << 16;
324		val |= *buf++ << 24;
325
326		ret = pci_user_write_config_dword(dev, vpd->cap + PCI_VPD_DATA, val);
327		if (ret < 0)
328			break;
329		ret = pci_user_write_config_word(dev, vpd->cap + PCI_VPD_ADDR,
330						 pos | PCI_VPD_ADDR_F);
331		if (ret < 0)
332			break;
333
334		vpd->busy = true;
335		vpd->flag = 0;
336		ret = pci_vpd_pci22_wait(dev);
337		if (ret < 0)
338			break;
339
340		pos += sizeof(u32);
341	}
342out:
343	mutex_unlock(&vpd->lock);
344	return ret ? ret : count;
345}
346
347static void pci_vpd_pci22_release(struct pci_dev *dev)
348{
349	kfree(container_of(dev->vpd, struct pci_vpd_pci22, base));
350}
351
352static const struct pci_vpd_ops pci_vpd_pci22_ops = {
353	.read = pci_vpd_pci22_read,
354	.write = pci_vpd_pci22_write,
355	.release = pci_vpd_pci22_release,
356};
357
358int pci_vpd_pci22_init(struct pci_dev *dev)
359{
360	struct pci_vpd_pci22 *vpd;
361	u8 cap;
362
363	cap = pci_find_capability(dev, PCI_CAP_ID_VPD);
364	if (!cap)
365		return -ENODEV;
366	vpd = kzalloc(sizeof(*vpd), GFP_ATOMIC);
367	if (!vpd)
368		return -ENOMEM;
369
370	vpd->base.len = PCI_VPD_PCI22_SIZE;
371	vpd->base.ops = &pci_vpd_pci22_ops;
372	mutex_init(&vpd->lock);
373	vpd->cap = cap;
374	vpd->busy = false;
375	dev->vpd = &vpd->base;
376	return 0;
377}
378
379/**
380 * pci_vpd_truncate - Set available Vital Product Data size
381 * @dev:	pci device struct
382 * @size:	available memory in bytes
383 *
384 * Adjust size of available VPD area.
385 */
386int pci_vpd_truncate(struct pci_dev *dev, size_t size)
387{
388	if (!dev->vpd)
389		return -EINVAL;
390
391	/* limited by the access method */
392	if (size > dev->vpd->len)
393		return -EINVAL;
394
395	dev->vpd->len = size;
396	if (dev->vpd->attr)
397		dev->vpd->attr->size = size;
398
399	return 0;
400}
401EXPORT_SYMBOL(pci_vpd_truncate);
402
403/**
404 * pci_block_user_cfg_access - Block userspace PCI config reads/writes
405 * @dev:	pci device struct
406 *
407 * When user access is blocked, any reads or writes to config space will
408 * sleep until access is unblocked again.  We don't allow nesting of
409 * block/unblock calls.
410 */
411void pci_block_user_cfg_access(struct pci_dev *dev)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
412{
413	unsigned long flags;
414	int was_blocked;
415
416	raw_spin_lock_irqsave(&pci_lock, flags);
417	was_blocked = dev->block_ucfg_access;
418	dev->block_ucfg_access = 1;
 
 
419	raw_spin_unlock_irqrestore(&pci_lock, flags);
420
421	/* If we BUG() inside the pci_lock, we're guaranteed to hose
422	 * the machine */
423	BUG_ON(was_blocked);
424}
425EXPORT_SYMBOL_GPL(pci_block_user_cfg_access);
426
427/**
428 * pci_unblock_user_cfg_access - Unblock userspace PCI config reads/writes
429 * @dev:	pci device struct
430 *
431 * This function allows userspace PCI config accesses to resume.
432 */
433void pci_unblock_user_cfg_access(struct pci_dev *dev)
434{
435	unsigned long flags;
436
437	raw_spin_lock_irqsave(&pci_lock, flags);
438
439	/* This indicates a problem in the caller, but we don't need
440	 * to kill them, unlike a double-block above. */
441	WARN_ON(!dev->block_ucfg_access);
442
443	dev->block_ucfg_access = 0;
444	wake_up_all(&pci_ucfg_wait);
445	raw_spin_unlock_irqrestore(&pci_lock, flags);
446}
447EXPORT_SYMBOL_GPL(pci_unblock_user_cfg_access);