linux/drivers/infiniband/hw/ipath/ipath_fs.c
<<
>>
Prefs
   1/*
   2 * Copyright (c) 2006, 2007 QLogic Corporation. All rights reserved.
   3 * Copyright (c) 2006 PathScale, Inc. All rights reserved.
   4 *
   5 * This software is available to you under a choice of one of two
   6 * licenses.  You may choose to be licensed under the terms of the GNU
   7 * General Public License (GPL) Version 2, available from the file
   8 * COPYING in the main directory of this source tree, or the
   9 * OpenIB.org BSD license below:
  10 *
  11 *     Redistribution and use in source and binary forms, with or
  12 *     without modification, are permitted provided that the following
  13 *     conditions are met:
  14 *
  15 *      - Redistributions of source code must retain the above
  16 *        copyright notice, this list of conditions and the following
  17 *        disclaimer.
  18 *
  19 *      - Redistributions in binary form must reproduce the above
  20 *        copyright notice, this list of conditions and the following
  21 *        disclaimer in the documentation and/or other materials
  22 *        provided with the distribution.
  23 *
  24 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  25 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  26 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  27 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  28 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  29 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  30 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  31 * SOFTWARE.
  32 */
  33
  34#include <linux/module.h>
  35#include <linux/fs.h>
  36#include <linux/mount.h>
  37#include <linux/pagemap.h>
  38#include <linux/init.h>
  39#include <linux/namei.h>
  40#include <linux/slab.h>
  41
  42#include "ipath_kernel.h"
  43
  44#define IPATHFS_MAGIC 0x726a77
  45
  46static struct super_block *ipath_super;
  47
  48static int ipathfs_mknod(struct inode *dir, struct dentry *dentry,
  49                         umode_t mode, const struct file_operations *fops,
  50                         void *data)
  51{
  52        int error;
  53        struct inode *inode = new_inode(dir->i_sb);
  54
  55        if (!inode) {
  56                error = -EPERM;
  57                goto bail;
  58        }
  59
  60        inode->i_ino = get_next_ino();
  61        inode->i_mode = mode;
  62        inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
  63        inode->i_private = data;
  64        if (S_ISDIR(mode)) {
  65                inode->i_op = &simple_dir_inode_operations;
  66                inc_nlink(inode);
  67                inc_nlink(dir);
  68        }
  69
  70        inode->i_fop = fops;
  71
  72        d_instantiate(dentry, inode);
  73        error = 0;
  74
  75bail:
  76        return error;
  77}
  78
  79static int create_file(const char *name, umode_t mode,
  80                       struct dentry *parent, struct dentry **dentry,
  81                       const struct file_operations *fops, void *data)
  82{
  83        int error;
  84
  85        *dentry = NULL;
  86        mutex_lock(&parent->d_inode->i_mutex);
  87        *dentry = lookup_one_len(name, parent, strlen(name));
  88        if (!IS_ERR(*dentry))
  89                error = ipathfs_mknod(parent->d_inode, *dentry,
  90                                      mode, fops, data);
  91        else
  92                error = PTR_ERR(*dentry);
  93        mutex_unlock(&parent->d_inode->i_mutex);
  94
  95        return error;
  96}
  97
  98static ssize_t atomic_stats_read(struct file *file, char __user *buf,
  99                                 size_t count, loff_t *ppos)
 100{
 101        return simple_read_from_buffer(buf, count, ppos, &ipath_stats,
 102                                       sizeof ipath_stats);
 103}
 104
 105static const struct file_operations atomic_stats_ops = {
 106        .read = atomic_stats_read,
 107        .llseek = default_llseek,
 108};
 109
 110static ssize_t atomic_counters_read(struct file *file, char __user *buf,
 111                                    size_t count, loff_t *ppos)
 112{
 113        struct infinipath_counters counters;
 114        struct ipath_devdata *dd;
 115
 116        dd = file_inode(file)->i_private;
 117        dd->ipath_f_read_counters(dd, &counters);
 118
 119        return simple_read_from_buffer(buf, count, ppos, &counters,
 120                                       sizeof counters);
 121}
 122
 123static const struct file_operations atomic_counters_ops = {
 124        .read = atomic_counters_read,
 125        .llseek = default_llseek,
 126};
 127
 128static ssize_t flash_read(struct file *file, char __user *buf,
 129                          size_t count, loff_t *ppos)
 130{
 131        struct ipath_devdata *dd;
 132        ssize_t ret;
 133        loff_t pos;
 134        char *tmp;
 135
 136        pos = *ppos;
 137
 138        if ( pos < 0) {
 139                ret = -EINVAL;
 140                goto bail;
 141        }
 142
 143        if (pos >= sizeof(struct ipath_flash)) {
 144                ret = 0;
 145                goto bail;
 146        }
 147
 148        if (count > sizeof(struct ipath_flash) - pos)
 149                count = sizeof(struct ipath_flash) - pos;
 150
 151        tmp = kmalloc(count, GFP_KERNEL);
 152        if (!tmp) {
 153                ret = -ENOMEM;
 154                goto bail;
 155        }
 156
 157        dd = file_inode(file)->i_private;
 158        if (ipath_eeprom_read(dd, pos, tmp, count)) {
 159                ipath_dev_err(dd, "failed to read from flash\n");
 160                ret = -ENXIO;
 161                goto bail_tmp;
 162        }
 163
 164        if (copy_to_user(buf, tmp, count)) {
 165                ret = -EFAULT;
 166                goto bail_tmp;
 167        }
 168
 169        *ppos = pos + count;
 170        ret = count;
 171
 172bail_tmp:
 173        kfree(tmp);
 174
 175bail:
 176        return ret;
 177}
 178
 179static ssize_t flash_write(struct file *file, const char __user *buf,
 180                           size_t count, loff_t *ppos)
 181{
 182        struct ipath_devdata *dd;
 183        ssize_t ret;
 184        loff_t pos;
 185        char *tmp;
 186
 187        pos = *ppos;
 188
 189        if (pos != 0) {
 190                ret = -EINVAL;
 191                goto bail;
 192        }
 193
 194        if (count != sizeof(struct ipath_flash)) {
 195                ret = -EINVAL;
 196                goto bail;
 197        }
 198
 199        tmp = kmalloc(count, GFP_KERNEL);
 200        if (!tmp) {
 201                ret = -ENOMEM;
 202                goto bail;
 203        }
 204
 205        if (copy_from_user(tmp, buf, count)) {
 206                ret = -EFAULT;
 207                goto bail_tmp;
 208        }
 209
 210        dd = file_inode(file)->i_private;
 211        if (ipath_eeprom_write(dd, pos, tmp, count)) {
 212                ret = -ENXIO;
 213                ipath_dev_err(dd, "failed to write to flash\n");
 214                goto bail_tmp;
 215        }
 216
 217        *ppos = pos + count;
 218        ret = count;
 219
 220bail_tmp:
 221        kfree(tmp);
 222
 223bail:
 224        return ret;
 225}
 226
 227static const struct file_operations flash_ops = {
 228        .read = flash_read,
 229        .write = flash_write,
 230        .llseek = default_llseek,
 231};
 232
 233static int create_device_files(struct super_block *sb,
 234                               struct ipath_devdata *dd)
 235{
 236        struct dentry *dir, *tmp;
 237        char unit[10];
 238        int ret;
 239
 240        snprintf(unit, sizeof unit, "%02d", dd->ipath_unit);
 241        ret = create_file(unit, S_IFDIR|S_IRUGO|S_IXUGO, sb->s_root, &dir,
 242                          &simple_dir_operations, dd);
 243        if (ret) {
 244                printk(KERN_ERR "create_file(%s) failed: %d\n", unit, ret);
 245                goto bail;
 246        }
 247
 248        ret = create_file("atomic_counters", S_IFREG|S_IRUGO, dir, &tmp,
 249                          &atomic_counters_ops, dd);
 250        if (ret) {
 251                printk(KERN_ERR "create_file(%s/atomic_counters) "
 252                       "failed: %d\n", unit, ret);
 253                goto bail;
 254        }
 255
 256        ret = create_file("flash", S_IFREG|S_IWUSR|S_IRUGO, dir, &tmp,
 257                          &flash_ops, dd);
 258        if (ret) {
 259                printk(KERN_ERR "create_file(%s/flash) "
 260                       "failed: %d\n", unit, ret);
 261                goto bail;
 262        }
 263
 264bail:
 265        return ret;
 266}
 267
 268static int remove_file(struct dentry *parent, char *name)
 269{
 270        struct dentry *tmp;
 271        int ret;
 272
 273        tmp = lookup_one_len(name, parent, strlen(name));
 274
 275        if (IS_ERR(tmp)) {
 276                ret = PTR_ERR(tmp);
 277                goto bail;
 278        }
 279
 280        spin_lock(&tmp->d_lock);
 281        if (!(d_unhashed(tmp) && tmp->d_inode)) {
 282                dget_dlock(tmp);
 283                __d_drop(tmp);
 284                spin_unlock(&tmp->d_lock);
 285                simple_unlink(parent->d_inode, tmp);
 286        } else
 287                spin_unlock(&tmp->d_lock);
 288
 289        ret = 0;
 290bail:
 291        /*
 292         * We don't expect clients to care about the return value, but
 293         * it's there if they need it.
 294         */
 295        return ret;
 296}
 297
 298static int remove_device_files(struct super_block *sb,
 299                               struct ipath_devdata *dd)
 300{
 301        struct dentry *dir, *root;
 302        char unit[10];
 303        int ret;
 304
 305        root = dget(sb->s_root);
 306        mutex_lock(&root->d_inode->i_mutex);
 307        snprintf(unit, sizeof unit, "%02d", dd->ipath_unit);
 308        dir = lookup_one_len(unit, root, strlen(unit));
 309
 310        if (IS_ERR(dir)) {
 311                ret = PTR_ERR(dir);
 312                printk(KERN_ERR "Lookup of %s failed\n", unit);
 313                goto bail;
 314        }
 315
 316        remove_file(dir, "flash");
 317        remove_file(dir, "atomic_counters");
 318        d_delete(dir);
 319        ret = simple_rmdir(root->d_inode, dir);
 320
 321bail:
 322        mutex_unlock(&root->d_inode->i_mutex);
 323        dput(root);
 324        return ret;
 325}
 326
 327static int ipathfs_fill_super(struct super_block *sb, void *data,
 328                              int silent)
 329{
 330        struct ipath_devdata *dd, *tmp;
 331        unsigned long flags;
 332        int ret;
 333
 334        static struct tree_descr files[] = {
 335                [2] = {"atomic_stats", &atomic_stats_ops, S_IRUGO},
 336                {""},
 337        };
 338
 339        ret = simple_fill_super(sb, IPATHFS_MAGIC, files);
 340        if (ret) {
 341                printk(KERN_ERR "simple_fill_super failed: %d\n", ret);
 342                goto bail;
 343        }
 344
 345        spin_lock_irqsave(&ipath_devs_lock, flags);
 346
 347        list_for_each_entry_safe(dd, tmp, &ipath_dev_list, ipath_list) {
 348                spin_unlock_irqrestore(&ipath_devs_lock, flags);
 349                ret = create_device_files(sb, dd);
 350                if (ret)
 351                        goto bail;
 352                spin_lock_irqsave(&ipath_devs_lock, flags);
 353        }
 354
 355        spin_unlock_irqrestore(&ipath_devs_lock, flags);
 356
 357bail:
 358        return ret;
 359}
 360
 361static struct dentry *ipathfs_mount(struct file_system_type *fs_type,
 362                        int flags, const char *dev_name, void *data)
 363{
 364        struct dentry *ret;
 365        ret = mount_single(fs_type, flags, data, ipathfs_fill_super);
 366        if (!IS_ERR(ret))
 367                ipath_super = ret->d_sb;
 368        return ret;
 369}
 370
 371static void ipathfs_kill_super(struct super_block *s)
 372{
 373        kill_litter_super(s);
 374        ipath_super = NULL;
 375}
 376
 377int ipathfs_add_device(struct ipath_devdata *dd)
 378{
 379        int ret;
 380
 381        if (ipath_super == NULL) {
 382                ret = 0;
 383                goto bail;
 384        }
 385
 386        ret = create_device_files(ipath_super, dd);
 387
 388bail:
 389        return ret;
 390}
 391
 392int ipathfs_remove_device(struct ipath_devdata *dd)
 393{
 394        int ret;
 395
 396        if (ipath_super == NULL) {
 397                ret = 0;
 398                goto bail;
 399        }
 400
 401        ret = remove_device_files(ipath_super, dd);
 402
 403bail:
 404        return ret;
 405}
 406
 407static struct file_system_type ipathfs_fs_type = {
 408        .owner =        THIS_MODULE,
 409        .name =         "ipathfs",
 410        .mount =        ipathfs_mount,
 411        .kill_sb =      ipathfs_kill_super,
 412};
 413MODULE_ALIAS_FS("ipathfs");
 414
 415int __init ipath_init_ipathfs(void)
 416{
 417        return register_filesystem(&ipathfs_fs_type);
 418}
 419
 420void __exit ipath_exit_ipathfs(void)
 421{
 422        unregister_filesystem(&ipathfs_fs_type);
 423}
 424