fs/ncpfs/file.c

   1 /*
   2  *  file.c
   3  *
   4  *  Copyright (C) 1995, 1996 by Volker Lendecke
   5  *  Modified 1997 Peter Waltenberg, Bill Hawes, David Woodhouse for 2.1 dcache
   6  *
   7  */
   8
   9 #include <asm/uaccess.h>
  10 #include <asm/system.h>
  11
  12 #include <linux/time.h>
  13 #include <linux/kernel.h>
  14 #include <linux/errno.h>
  15 #include <linux/fcntl.h>
  16 #include <linux/stat.h>
  17 #include <linux/mm.h>
  18 #include <linux/slab.h>
  19 #include <linux/vmalloc.h>
  20 #include <linux/sched.h>
  21 #include <linux/smp_lock.h>
  22
  23 #include <linux/ncp_fs.h>
  24 #include "ncplib_kernel.h"
  25
  26 static int ncp_fsync(struct file *file, struct dentry *dentry, int datasync)
  27 {
  28         return 0;
  29 }
  30
  31 /*
  32  * Open a file with the specified read/write mode.
  33  */
  34 int ncp_make_open(struct inode *inode, int right)
  35 {
  36         int error;
  37         int access;
  38
  39         error = -EINVAL;
  40         if (!inode) {
  41                 printk(KERN_ERR "ncp_make_open: got NULL inode\n");
  42                 goto out;
  43         }
  44
  45         DPRINTK("ncp_make_open: opened=%d, volume # %u, dir entry # %u\n",
  46                 atomic_read(&NCP_FINFO(inode)->opened),
  47                 NCP_FINFO(inode)->volNumber,
  48                 NCP_FINFO(inode)->dirEntNum);
  49         error = -EACCES;
  50         mutex_lock(&NCP_FINFO(inode)->open_mutex);
  51         if (!atomic_read(&NCP_FINFO(inode)->opened)) {
  52                 struct ncp_entry_info finfo;
  53                 int result;
  54
  55                 /* tries max. rights */
  56                 finfo.access = O_RDWR;
  57                 result = ncp_open_create_file_or_subdir(NCP_SERVER(inode),
  58                                         inode, NULL, OC_MODE_OPEN,
  59                                         0, AR_READ | AR_WRITE, &finfo);
  60                 if (!result)
  61                         goto update;
  62                 /* RDWR did not succeeded, try readonly or writeonly as requested */
  63                 switch (right) {
  64                         case O_RDONLY:
  65                                 finfo.access = O_RDONLY;
  66                                 result = ncp_open_create_file_or_subdir(NCP_SERVER(inode),
  67                                         inode, NULL, OC_MODE_OPEN,
  68                                         0, AR_READ, &finfo);
  69                                 break;
  70                         case O_WRONLY:
  71                                 finfo.access = O_WRONLY;
  72                                 result = ncp_open_create_file_or_subdir(NCP_SERVER(inode),
  73                                         inode, NULL, OC_MODE_OPEN,
  74                                         0, AR_WRITE, &finfo);
  75                                 break;
  76                 }
  77                 if (result) {
  78                         PPRINTK("ncp_make_open: failed, result=%d\n", result);
  79                         goto out_unlock;
  80                 }
  81                 /*
  82                  * Update the inode information.
  83                  */
  84         update:
  85                 ncp_update_inode(inode, &finfo);
  86                 atomic_set(&NCP_FINFO(inode)->opened, 1);
  87         }
  88
  89         access = NCP_FINFO(inode)->access;
  90         PPRINTK("ncp_make_open: file open, access=%x\n", access);
  91         if (access == right || access == O_RDWR) {
  92                 atomic_inc(&NCP_FINFO(inode)->opened);
  93                 error = 0;
  94         }
  95
  96 out_unlock:
  97         mutex_unlock(&NCP_FINFO(inode)->open_mutex);
  98 out:
  99         return error;
 100 }
 101
 102 static ssize_t
 103 ncp_file_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
 104 {
 105         struct dentry *dentry = file->f_path.dentry;
 106         struct inode *inode = dentry->d_inode;
 107         size_t already_read = 0;
 108         off_t pos;
 109         size_t bufsize;
 110         int error;
 111         void* freepage;
 112         size_t freelen;
 113
 114         DPRINTK("ncp_file_read: enter %s/%s\n",
 115                 dentry->d_parent->d_name.name, dentry->d_name.name);
 116
 117         if (!ncp_conn_valid(NCP_SERVER(inode)))
 118                 return -EIO;
 119
 120         pos = *ppos;
 121
 122         if ((ssize_t) count < 0) {
 123                 return -EINVAL;
 124         }
 125         if (!count)
 126                 return 0;
 127         if (pos > inode->i_sb->s_maxbytes)
 128                 return 0;
 129         if (pos + count > inode->i_sb->s_maxbytes) {
 130                 count = inode->i_sb->s_maxbytes - pos;
 131         }
 132
 133         error = ncp_make_open(inode, O_RDONLY);
 134         if (error) {
 135                 DPRINTK(KERN_ERR "ncp_file_read: open failed, error=%d\n", error);
 136                 return error;
 137         }
 138
 139         bufsize = NCP_SERVER(inode)->buffer_size;
 140
 141         error = -EIO;
 142         freelen = ncp_read_bounce_size(bufsize);
 143         freepage = vmalloc(freelen);
 144         if (!freepage)
 145                 goto outrel;
 146         error = 0;
 147         /* First read in as much as possible for each bufsize. */
 148         while (already_read < count) {
 149                 int read_this_time;
 150                 size_t to_read = min_t(unsigned int,
 151                                      bufsize - (pos % bufsize),
 152                                      count - already_read);
 153
 154                 error = ncp_read_bounce(NCP_SERVER(inode),
 155                                 NCP_FINFO(inode)->file_handle,
 156                                 pos, to_read, buf, &read_this_time,
 157                                 freepage, freelen);
 158                 if (error) {
 159                         error = -EIO;   /* NW errno -> Linux errno */
 160                         break;
 161                 }
 162                 pos += read_this_time;
 163                 buf += read_this_time;
 164                 already_read += read_this_time;
 165
 166                 if (read_this_time != to_read) {
 167                         break;
 168                 }
 169         }
 170         vfree(freepage);
 171
 172         *ppos = pos;
 173
 174         file_accessed(file);
 175
 176         DPRINTK("ncp_file_read: exit %s/%s\n",
 177                 dentry->d_parent->d_name.name, dentry->d_name.name);
 178 outrel:
 179         ncp_inode_close(inode);
 180         return already_read ? already_read : error;
 181 }
 182
 183 static ssize_t
 184 ncp_file_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
 185 {
 186         struct dentry *dentry = file->f_path.dentry;
 187         struct inode *inode = dentry->d_inode;
 188         size_t already_written = 0;
 189         off_t pos;
 190         size_t bufsize;
 191         int errno;
 192         void* bouncebuffer;
 193
 194         DPRINTK("ncp_file_write: enter %s/%s\n",
 195                 dentry->d_parent->d_name.name, dentry->d_name.name);
 196         if (!ncp_conn_valid(NCP_SERVER(inode)))
 197                 return -EIO;
 198         if ((ssize_t) count < 0)
 199                 return -EINVAL;
 200         pos = *ppos;
 201         if (file->f_flags & O_APPEND) {
 202                 pos = inode->i_size;
 203         }
 204
 205         if (pos + count > MAX_NON_LFS && !(file->f_flags&O_LARGEFILE)) {
 206                 if (pos >= MAX_NON_LFS) {
 207                         return -EFBIG;
 208                 }
 209                 if (count > MAX_NON_LFS - (u32)pos) {
 210                         count = MAX_NON_LFS - (u32)pos;
 211                 }
 212         }
 213         if (pos >= inode->i_sb->s_maxbytes) {
 214                 if (count || pos > inode->i_sb->s_maxbytes) {
 215                         return -EFBIG;
 216                 }
 217         }
 218         if (pos + count > inode->i_sb->s_maxbytes) {
 219                 count = inode->i_sb->s_maxbytes - pos;
 220         }
 221
 222         if (!count)
 223                 return 0;
 224         errno = ncp_make_open(inode, O_WRONLY);
 225         if (errno) {
 226                 DPRINTK(KERN_ERR "ncp_file_write: open failed, error=%d\n", errno);
 227                 return errno;
 228         }
 229         bufsize = NCP_SERVER(inode)->buffer_size;
 230
 231         already_written = 0;
 232
 233         bouncebuffer = vmalloc(bufsize);
 234         if (!bouncebuffer) {
 235                 errno = -EIO;   /* -ENOMEM */
 236                 goto outrel;
 237         }
 238         while (already_written < count) {
 239                 int written_this_time;
 240                 size_t to_write = min_t(unsigned int,
 241                                       bufsize - (pos % bufsize),
 242                                       count - already_written);
 243
 244                 if (copy_from_user(bouncebuffer, buf, to_write)) {
 245                         errno = -EFAULT;
 246                         break;
 247                 }
 248                 if (ncp_write_kernel(NCP_SERVER(inode),
 249                     NCP_FINFO(inode)->file_handle,
 250                     pos, to_write, bouncebuffer, &written_this_time) != 0) {
 251                         errno = -EIO;
 252                         break;
 253                 }
 254                 pos += written_this_time;
 255                 buf += written_this_time;
 256                 already_written += written_this_time;
 257
 258                 if (written_this_time != to_write) {
 259                         break;
 260                 }
 261         }
 262         vfree(bouncebuffer);
 263
 264         file_update_time(file);
 265
 266         *ppos = pos;
 267
 268         if (pos > inode->i_size) {
 269                 inode->i_size = pos;
 270         }
 271         DPRINTK("ncp_file_write: exit %s/%s\n",
 272                 dentry->d_parent->d_name.name, dentry->d_name.name);
 273 outrel:
 274         ncp_inode_close(inode);
 275         return already_written ? already_written : errno;
 276 }
 277
 278 static int ncp_release(struct inode *inode, struct file *file) {
 279         if (ncp_make_closed(inode)) {
 280                 DPRINTK("ncp_release: failed to close\n");
 281         }
 282         return 0;
 283 }
 284
 285 static loff_t ncp_remote_llseek(struct file *file, loff_t offset, int origin)
 286 {
 287         loff_t ret;
 288         lock_kernel();
 289         ret = generic_file_llseek_unlocked(file, offset, origin);
 290         unlock_kernel();
 291         return ret;
 292 }
 293
 294 const struct file_operations ncp_file_operations =
 295 {
 296         .llseek         = ncp_remote_llseek,
 297         .read           = ncp_file_read,
 298         .write          = ncp_file_write,
 299         .ioctl          = ncp_ioctl,
 300 #ifdef CONFIG_COMPAT
 301         .compat_ioctl   = ncp_compat_ioctl,
 302 #endif
 303         .mmap           = ncp_mmap,
 304         .release        = ncp_release,
 305         .fsync          = ncp_fsync,
 306 };
 307
 308 const struct inode_operations ncp_file_inode_operations =
 309 {
 310         .setattr        = ncp_notify_change,
 311 };