SAFE public projects git trees. - safe/jmp/linux-2.6/blob - 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
  21 #include <linux/ncp_fs.h>
  22 #include "ncplib_kernel.h"
  23
  24 static int ncp_fsync(struct file *file, struct dentry *dentry, int datasync)
  25 {
  26         return 0;
  27 }
  28
  29 /*
  30  * Open a file with the specified read/write mode.
  31  */
  32 int ncp_make_open(struct inode *inode, int right)
  33 {
  34         int error;
  35         int access;
  36
  37         error = -EINVAL;
  38         if (!inode) {
  39                 printk(KERN_ERR "ncp_make_open: got NULL inode\n");
  40                 goto out;
  41         }
  42
  43         DPRINTK("ncp_make_open: opened=%d, volume # %u, dir entry # %u\n",
  44                 atomic_read(&NCP_FINFO(inode)->opened),
  45                 NCP_FINFO(inode)->volNumber,
  46                 NCP_FINFO(inode)->dirEntNum);
  47         error = -EACCES;
  48         mutex_lock(&NCP_FINFO(inode)->open_mutex);
  49         if (!atomic_read(&NCP_FINFO(inode)->opened)) {
  50                 struct ncp_entry_info finfo;
  51                 int result;
  52
  53                 /* tries max. rights */
  54                 finfo.access = O_RDWR;
  55                 result = ncp_open_create_file_or_subdir(NCP_SERVER(inode),
  56                                         inode, NULL, OC_MODE_OPEN,
  57                                         0, AR_READ | AR_WRITE, &finfo);
  58                 if (!result)
  59                         goto update;
  60                 /* RDWR did not succeeded, try readonly or writeonly as requested */
  61                 switch (right) {
  62                         case O_RDONLY:
  63                                 finfo.access = O_RDONLY;
  64                                 result = ncp_open_create_file_or_subdir(NCP_SERVER(inode),
  65                                         inode, NULL, OC_MODE_OPEN,
  66                                         0, AR_READ, &finfo);
  67                                 break;
  68                         case O_WRONLY:
  69                                 finfo.access = O_WRONLY;
  70                                 result = ncp_open_create_file_or_subdir(NCP_SERVER(inode),
  71                                         inode, NULL, OC_MODE_OPEN,
  72                                         0, AR_WRITE, &finfo);
  73                                 break;
  74                 }
  75                 if (result) {
  76                         PPRINTK("ncp_make_open: failed, result=%d\n", result);
  77                         goto out_unlock;
  78                 }
  79                 /*
  80                  * Update the inode information.
  81                  */
  82         update:
  83                 ncp_update_inode(inode, &finfo);
  84                 atomic_set(&NCP_FINFO(inode)->opened, 1);
  85         }
  86
  87         access = NCP_FINFO(inode)->access;
  88         PPRINTK("ncp_make_open: file open, access=%x\n", access);
  89         if (access == right || access == O_RDWR) {
  90                 atomic_inc(&NCP_FINFO(inode)->opened);
  91                 error = 0;
  92         }
  93
  94 out_unlock:
  95         mutex_unlock(&NCP_FINFO(inode)->open_mutex);
  96 out:
  97         return error;
  98 }
  99
 100 static ssize_t
 101 ncp_file_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
 102 {
 103         struct dentry *dentry = file->f_path.dentry;
 104         struct inode *inode = dentry->d_inode;
 105         size_t already_read = 0;
 106         off_t pos;
 107         size_t bufsize;
 108         int error;
 109         void* freepage;
 110         size_t freelen;
 111
 112         DPRINTK("ncp_file_read: enter %s/%s\n",
 113                 dentry->d_parent->d_name.name, dentry->d_name.name);
 114
 115         if (!ncp_conn_valid(NCP_SERVER(inode)))
 116                 return -EIO;
 117
 118         pos = *ppos;
 119
 120         if ((ssize_t) count < 0) {
 121                 return -EINVAL;
 122         }
 123         if (!count)
 124                 return 0;
 125         if (pos > inode->i_sb->s_maxbytes)
 126                 return 0;
 127         if (pos + count > inode->i_sb->s_maxbytes) {
 128                 count = inode->i_sb->s_maxbytes - pos;
 129         }
 130
 131         error = ncp_make_open(inode, O_RDONLY);
 132         if (error) {
 133                 DPRINTK(KERN_ERR "ncp_file_read: open failed, error=%d\n", error);
 134                 return error;
 135         }
 136
 137         bufsize = NCP_SERVER(inode)->buffer_size;
 138
 139         error = -EIO;
 140         freelen = ncp_read_bounce_size(bufsize);
 141         freepage = vmalloc(freelen);
 142         if (!freepage)
 143                 goto outrel;
 144         error = 0;
 145         /* First read in as much as possible for each bufsize. */
 146         while (already_read < count) {
 147                 int read_this_time;
 148                 size_t to_read = min_t(unsigned int,
 149                                      bufsize - (pos % bufsize),
 150                                      count - already_read);
 151
 152                 error = ncp_read_bounce(NCP_SERVER(inode),
 153                                 NCP_FINFO(inode)->file_handle,
 154                                 pos, to_read, buf, &read_this_time,
 155                                 freepage, freelen);
 156                 if (error) {
 157                         error = -EIO;   /* NW errno -> Linux errno */
 158                         break;
 159                 }
 160                 pos += read_this_time;
 161                 buf += read_this_time;
 162                 already_read += read_this_time;
 163
 164                 if (read_this_time != to_read) {
 165                         break;
 166                 }
 167         }
 168         vfree(freepage);
 169
 170         *ppos = pos;
 171
 172         file_accessed(file);
 173
 174         DPRINTK("ncp_file_read: exit %s/%s\n",
 175                 dentry->d_parent->d_name.name, dentry->d_name.name);
 176 outrel:
 177         ncp_inode_close(inode);
 178         return already_read ? already_read : error;
 179 }
 180
 181 static ssize_t
 182 ncp_file_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
 183 {
 184         struct dentry *dentry = file->f_path.dentry;
 185         struct inode *inode = dentry->d_inode;
 186         size_t already_written = 0;
 187         off_t pos;
 188         size_t bufsize;
 189         int errno;
 190         void* bouncebuffer;
 191
 192         DPRINTK("ncp_file_write: enter %s/%s\n",
 193                 dentry->d_parent->d_name.name, dentry->d_name.name);
 194         if (!ncp_conn_valid(NCP_SERVER(inode)))
 195                 return -EIO;
 196         if ((ssize_t) count < 0)
 197                 return -EINVAL;
 198         pos = *ppos;
 199         if (file->f_flags & O_APPEND) {
 200                 pos = inode->i_size;
 201         }
 202
 203         if (pos + count > MAX_NON_LFS && !(file->f_flags&O_LARGEFILE)) {
 204                 if (pos >= MAX_NON_LFS) {
 205                         send_sig(SIGXFSZ, current, 0);
 206                         return -EFBIG;
 207                 }
 208                 if (count > MAX_NON_LFS - (u32)pos) {
 209                         count = MAX_NON_LFS - (u32)pos;
 210                 }
 211         }
 212         if (pos >= inode->i_sb->s_maxbytes) {
 213                 if (count || pos > inode->i_sb->s_maxbytes) {
 214                         send_sig(SIGXFSZ, current, 0);
 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 const struct file_operations ncp_file_operations =
 286 {
 287         .llseek         = remote_llseek,
 288         .read           = ncp_file_read,
 289         .write          = ncp_file_write,
 290         .ioctl          = ncp_ioctl,
 291 #ifdef CONFIG_COMPAT
 292         .compat_ioctl   = ncp_compat_ioctl,
 293 #endif
 294         .mmap           = ncp_mmap,
 295         .release        = ncp_release,
 296         .fsync          = ncp_fsync,
 297 };
 298
 299 const struct inode_operations ncp_file_inode_operations =
 300 {
 301         .setattr        = ncp_notify_change,
 302 };