Showing error 887

User: Jiri Slaby
Error type: Resource Leak
Error type description: The code omits to put the resource to the system for reuse
File location: drivers/pci/proc.c
Line in file: 327
Project: Linux Kernel
Project version: 2.6.28
Tools: Stanse (1.2)
Entered: 2011-11-07 22:41:42 UTC

Source: 

  1/*
  2 *        Procfs interface for the PCI bus.
  3 *
  4 *        Copyright (c) 1997--1999 Martin Mares <mj@ucw.cz>
  5 */
  6
  7#include <linux/init.h>
  8#include <linux/pci.h>
  9#include <linux/module.h>
 10#include <linux/proc_fs.h>
 11#include <linux/seq_file.h>
 12#include <linux/smp_lock.h>
 13#include <linux/capability.h>
 14#include <asm/uaccess.h>
 15#include <asm/byteorder.h>
 16#include "pci.h"
 17
 18static int proc_initialized;        /* = 0 */
 19
 20static loff_t
 21proc_bus_pci_lseek(struct file *file, loff_t off, int whence)
 22{
 23        loff_t new = -1;
 24        struct inode *inode = file->f_path.dentry->d_inode;
 25
 26        mutex_lock(&inode->i_mutex);
 27        switch (whence) {
 28        case 0:
 29                new = off;
 30                break;
 31        case 1:
 32                new = file->f_pos + off;
 33                break;
 34        case 2:
 35                new = inode->i_size + off;
 36                break;
 37        }
 38        if (new < 0 || new > inode->i_size)
 39                new = -EINVAL;
 40        else
 41                file->f_pos = new;
 42        mutex_unlock(&inode->i_mutex);
 43        return new;
 44}
 45
 46static ssize_t
 47proc_bus_pci_read(struct file *file, char __user *buf, size_t nbytes, loff_t *ppos)
 48{
 49        const struct inode *ino = file->f_path.dentry->d_inode;
 50        const struct proc_dir_entry *dp = PDE(ino);
 51        struct pci_dev *dev = dp->data;
 52        unsigned int pos = *ppos;
 53        unsigned int cnt, size;
 54
 55        /*
 56         * Normal users can read only the standardized portion of the
 57         * configuration space as several chips lock up when trying to read
 58         * undefined locations (think of Intel PIIX4 as a typical example).
 59         */
 60
 61        if (capable(CAP_SYS_ADMIN))
 62                size = dp->size;
 63        else if (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
 64                size = 128;
 65        else
 66                size = 64;
 67
 68        if (pos >= size)
 69                return 0;
 70        if (nbytes >= size)
 71                nbytes = size;
 72        if (pos + nbytes > size)
 73                nbytes = size - pos;
 74        cnt = nbytes;
 75
 76        if (!access_ok(VERIFY_WRITE, buf, cnt))
 77                return -EINVAL;
 78
 79        if ((pos & 1) && cnt) {
 80                unsigned char val;
 81                pci_user_read_config_byte(dev, pos, &val);
 82                __put_user(val, buf);
 83                buf++;
 84                pos++;
 85                cnt--;
 86        }
 87
 88        if ((pos & 3) && cnt > 2) {
 89                unsigned short val;
 90                pci_user_read_config_word(dev, pos, &val);
 91                __put_user(cpu_to_le16(val), (__le16 __user *) buf);
 92                buf += 2;
 93                pos += 2;
 94                cnt -= 2;
 95        }
 96
 97        while (cnt >= 4) {
 98                unsigned int val;
 99                pci_user_read_config_dword(dev, pos, &val);
100                __put_user(cpu_to_le32(val), (__le32 __user *) buf);
101                buf += 4;
102                pos += 4;
103                cnt -= 4;
104        }
105
106        if (cnt >= 2) {
107                unsigned short val;
108                pci_user_read_config_word(dev, pos, &val);
109                __put_user(cpu_to_le16(val), (__le16 __user *) buf);
110                buf += 2;
111                pos += 2;
112                cnt -= 2;
113        }
114
115        if (cnt) {
116                unsigned char val;
117                pci_user_read_config_byte(dev, pos, &val);
118                __put_user(val, buf);
119                buf++;
120                pos++;
121                cnt--;
122        }
123
124        *ppos = pos;
125        return nbytes;
126}
127
128static ssize_t
129proc_bus_pci_write(struct file *file, const char __user *buf, size_t nbytes, loff_t *ppos)
130{
131        struct inode *ino = file->f_path.dentry->d_inode;
132        const struct proc_dir_entry *dp = PDE(ino);
133        struct pci_dev *dev = dp->data;
134        int pos = *ppos;
135        int size = dp->size;
136        int cnt;
137
138        if (pos >= size)
139                return 0;
140        if (nbytes >= size)
141                nbytes = size;
142        if (pos + nbytes > size)
143                nbytes = size - pos;
144        cnt = nbytes;
145
146        if (!access_ok(VERIFY_READ, buf, cnt))
147                return -EINVAL;
148
149        if ((pos & 1) && cnt) {
150                unsigned char val;
151                __get_user(val, buf);
152                pci_user_write_config_byte(dev, pos, val);
153                buf++;
154                pos++;
155                cnt--;
156        }
157
158        if ((pos & 3) && cnt > 2) {
159                __le16 val;
160                __get_user(val, (__le16 __user *) buf);
161                pci_user_write_config_word(dev, pos, le16_to_cpu(val));
162                buf += 2;
163                pos += 2;
164                cnt -= 2;
165        }
166
167        while (cnt >= 4) {
168                __le32 val;
169                __get_user(val, (__le32 __user *) buf);
170                pci_user_write_config_dword(dev, pos, le32_to_cpu(val));
171                buf += 4;
172                pos += 4;
173                cnt -= 4;
174        }
175
176        if (cnt >= 2) {
177                __le16 val;
178                __get_user(val, (__le16 __user *) buf);
179                pci_user_write_config_word(dev, pos, le16_to_cpu(val));
180                buf += 2;
181                pos += 2;
182                cnt -= 2;
183        }
184
185        if (cnt) {
186                unsigned char val;
187                __get_user(val, buf);
188                pci_user_write_config_byte(dev, pos, val);
189                buf++;
190                pos++;
191                cnt--;
192        }
193
194        *ppos = pos;
195        i_size_write(ino, dp->size);
196        return nbytes;
197}
198
199struct pci_filp_private {
200        enum pci_mmap_state mmap_state;
201        int write_combine;
202};
203
204static long proc_bus_pci_ioctl(struct file *file, unsigned int cmd,
205                               unsigned long arg)
206{
207        const struct proc_dir_entry *dp = PDE(file->f_dentry->d_inode);
208        struct pci_dev *dev = dp->data;
209#ifdef HAVE_PCI_MMAP
210        struct pci_filp_private *fpriv = file->private_data;
211#endif /* HAVE_PCI_MMAP */
212        int ret = 0;
213
214        lock_kernel();
215
216        switch (cmd) {
217        case PCIIOC_CONTROLLER:
218                ret = pci_domain_nr(dev->bus);
219                break;
220
221#ifdef HAVE_PCI_MMAP
222        case PCIIOC_MMAP_IS_IO:
223                fpriv->mmap_state = pci_mmap_io;
224                break;
225
226        case PCIIOC_MMAP_IS_MEM:
227                fpriv->mmap_state = pci_mmap_mem;
228                break;
229
230        case PCIIOC_WRITE_COMBINE:
231                if (arg)
232                        fpriv->write_combine = 1;
233                else
234                        fpriv->write_combine = 0;
235                break;
236
237#endif /* HAVE_PCI_MMAP */
238
239        default:
240                ret = -EINVAL;
241                break;
242        };
243
244        unlock_kernel();
245        return ret;
246}
247
248#ifdef HAVE_PCI_MMAP
249static int proc_bus_pci_mmap(struct file *file, struct vm_area_struct *vma)
250{
251        struct inode *inode = file->f_path.dentry->d_inode;
252        const struct proc_dir_entry *dp = PDE(inode);
253        struct pci_dev *dev = dp->data;
254        struct pci_filp_private *fpriv = file->private_data;
255        int ret;
256
257        if (!capable(CAP_SYS_RAWIO))
258                return -EPERM;
259
260        ret = pci_mmap_page_range(dev, vma,
261                                  fpriv->mmap_state,
262                                  fpriv->write_combine);
263        if (ret < 0)
264                return ret;
265
266        return 0;
267}
268
269static int proc_bus_pci_open(struct inode *inode, struct file *file)
270{
271        struct pci_filp_private *fpriv = kmalloc(sizeof(*fpriv), GFP_KERNEL);
272
273        if (!fpriv)
274                return -ENOMEM;
275
276        fpriv->mmap_state = pci_mmap_io;
277        fpriv->write_combine = 0;
278
279        file->private_data = fpriv;
280
281        return 0;
282}
283
284static int proc_bus_pci_release(struct inode *inode, struct file *file)
285{
286        kfree(file->private_data);
287        file->private_data = NULL;
288
289        return 0;
290}
291#endif /* HAVE_PCI_MMAP */
292
293static const struct file_operations proc_bus_pci_operations = {
294        .owner                = THIS_MODULE,
295        .llseek                = proc_bus_pci_lseek,
296        .read                = proc_bus_pci_read,
297        .write                = proc_bus_pci_write,
298        .unlocked_ioctl        = proc_bus_pci_ioctl,
299#ifdef HAVE_PCI_MMAP
300        .open                = proc_bus_pci_open,
301        .release        = proc_bus_pci_release,
302        .mmap                = proc_bus_pci_mmap,
303#ifdef HAVE_ARCH_PCI_GET_UNMAPPED_AREA
304        .get_unmapped_area = get_pci_unmapped_area,
305#endif /* HAVE_ARCH_PCI_GET_UNMAPPED_AREA */
306#endif /* HAVE_PCI_MMAP */
307};
308
309/* iterator */
310static void *pci_seq_start(struct seq_file *m, loff_t *pos)
311{
312        struct pci_dev *dev = NULL;
313        loff_t n = *pos;
314
315        for_each_pci_dev(dev) {
316                if (!n--)
317                        break;
318        }
319        return dev;
320}
321
322static void *pci_seq_next(struct seq_file *m, void *v, loff_t *pos)
323{
324        struct pci_dev *dev = v;
325
326        (*pos)++;
327        dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev);
328        return dev;
329}
330
331static void pci_seq_stop(struct seq_file *m, void *v)
332{
333        if (v) {
334                struct pci_dev *dev = v;
335                pci_dev_put(dev);
336        }
337}
338
339static int show_device(struct seq_file *m, void *v)
340{
341        const struct pci_dev *dev = v;
342        const struct pci_driver *drv;
343        int i;
344
345        if (dev == NULL)
346                return 0;
347
348        drv = pci_dev_driver(dev);
349        seq_printf(m, "%02x%02x\t%04x%04x\t%x",
350                        dev->bus->number,
351                        dev->devfn,
352                        dev->vendor,
353                        dev->device,
354                        dev->irq);
355        /* Here should be 7 and not PCI_NUM_RESOURCES as we need to preserve compatibility */
356        for (i=0; i<7; i++) {
357                resource_size_t start, end;
358                pci_resource_to_user(dev, i, &dev->resource[i], &start, &end);
359                seq_printf(m, "\t%16llx",
360                        (unsigned long long)(start |
361                        (dev->resource[i].flags & PCI_REGION_FLAG_MASK)));
362        }
363        for (i=0; i<7; i++) {
364                resource_size_t start, end;
365                pci_resource_to_user(dev, i, &dev->resource[i], &start, &end);
366                seq_printf(m, "\t%16llx",
367                        dev->resource[i].start < dev->resource[i].end ?
368                        (unsigned long long)(end - start) + 1 : 0);
369        }
370        seq_putc(m, '\t');
371        if (drv)
372                seq_printf(m, "%s", drv->name);
373        seq_putc(m, '\n');
374        return 0;
375}
376
377static const struct seq_operations proc_bus_pci_devices_op = {
378        .start        = pci_seq_start,
379        .next        = pci_seq_next,
380        .stop        = pci_seq_stop,
381        .show        = show_device
382};
383
384static struct proc_dir_entry *proc_bus_pci_dir;
385
386int pci_proc_attach_device(struct pci_dev *dev)
387{
388        struct pci_bus *bus = dev->bus;
389        struct proc_dir_entry *e;
390        char name[16];
391
392        if (!proc_initialized)
393                return -EACCES;
394
395        if (!bus->procdir) {
396                if (pci_proc_domain(bus)) {
397                        sprintf(name, "%04x:%02x", pci_domain_nr(bus),
398                                        bus->number);
399                } else {
400                        sprintf(name, "%02x", bus->number);
401                }
402                bus->procdir = proc_mkdir(name, proc_bus_pci_dir);
403                if (!bus->procdir)
404                        return -ENOMEM;
405        }
406
407        sprintf(name, "%02x.%x", PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn));
408        e = proc_create_data(name, S_IFREG | S_IRUGO | S_IWUSR, bus->procdir,
409                             &proc_bus_pci_operations, dev);
410        if (!e)
411                return -ENOMEM;
412        e->size = dev->cfg_size;
413        dev->procent = e;
414
415        return 0;
416}
417
418int pci_proc_detach_device(struct pci_dev *dev)
419{
420        struct proc_dir_entry *e;
421
422        if ((e = dev->procent)) {
423                if (atomic_read(&e->count) > 1)
424                        return -EBUSY;
425                remove_proc_entry(e->name, dev->bus->procdir);
426                dev->procent = NULL;
427        }
428        return 0;
429}
430
431#if 0
432int pci_proc_attach_bus(struct pci_bus* bus)
433{
434        struct proc_dir_entry *de = bus->procdir;
435
436        if (!proc_initialized)
437                return -EACCES;
438
439        if (!de) {
440                char name[16];
441                sprintf(name, "%02x", bus->number);
442                de = bus->procdir = proc_mkdir(name, proc_bus_pci_dir);
443                if (!de)
444                        return -ENOMEM;
445        }
446        return 0;
447}
448#endif  /*  0  */
449
450int pci_proc_detach_bus(struct pci_bus* bus)
451{
452        struct proc_dir_entry *de = bus->procdir;
453        if (de)
454                remove_proc_entry(de->name, proc_bus_pci_dir);
455        return 0;
456}
457
458static int proc_bus_pci_dev_open(struct inode *inode, struct file *file)
459{
460        return seq_open(file, &proc_bus_pci_devices_op);
461}
462static const struct file_operations proc_bus_pci_dev_operations = {
463        .owner                = THIS_MODULE,
464        .open                = proc_bus_pci_dev_open,
465        .read                = seq_read,
466        .llseek                = seq_lseek,
467        .release        = seq_release,
468};
469
470static int __init pci_proc_init(void)
471{
472        struct pci_dev *dev = NULL;
473        proc_bus_pci_dir = proc_mkdir("bus/pci", NULL);
474        proc_create("devices", 0, proc_bus_pci_dir,
475                    &proc_bus_pci_dev_operations);
476        proc_initialized = 1;
477        while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {
478                pci_proc_attach_device(dev);
479        }
480        return 0;
481}
482
483device_initcall(pci_proc_init);
484
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