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