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/vmalloc.h>
  19 #include <linux/sched.h>
  20 #include <linux/smp_lock.h>
  21
  22 #include <linux/ncp_fs.h>
  23 #include "ncplib_kernel.h"
  24
  25 static int ncp_fsync(struct file *file, 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         pos = *ppos;
 117
 118         if ((ssize_t) count < 0) {
 119                 return -EINVAL;
 120         }
 121         if (!count)
 122                 return 0;
 123         if (pos > inode->i_sb->s_maxbytes)
 124                 return 0;
 125         if (pos + count > inode->i_sb->s_maxbytes) {
 126                 count = inode->i_sb->s_maxbytes - pos;
 127         }
 128
 129         error = ncp_make_open(inode, O_RDONLY);
 130         if (error) {
 131                 DPRINTK(KERN_ERR "ncp_file_read: open failed, error=%d\n", error);
 132                 return error;
 133         }
 134
 135         bufsize = NCP_SERVER(inode)->buffer_size;
 136
 137         error = -EIO;
 138         freelen = ncp_read_bounce_size(bufsize);
 139         freepage = vmalloc(freelen);
 140         if (!freepage)
 141                 goto outrel;
 142         error = 0;
 143         /* First read in as much as possible for each bufsize. */
 144         while (already_read < count) {
 145                 int read_this_time;
 146                 size_t to_read = min_t(unsigned int,
 147                                      bufsize - (pos % bufsize),
 148                                      count - already_read);
 149
 150                 error = ncp_read_bounce(NCP_SERVER(inode),
 151                                 NCP_FINFO(inode)->file_handle,
 152                                 pos, to_read, buf, &read_this_time,
 153                                 freepage, freelen);
 154                 if (error) {
 155                         error = -EIO;   /* NW errno -> Linux errno */
 156                         break;
 157                 }
 158                 pos += read_this_time;
 159                 buf += read_this_time;
 160                 already_read += read_this_time;
 161
 162                 if (read_this_time != to_read) {
 163                         break;
 164                 }
 165         }
 166         vfree(freepage);
 167
 168         *ppos = pos;
 169
 170         file_accessed(file);
 171
 172         DPRINTK("ncp_file_read: exit %s/%s\n",
 173                 dentry->d_parent->d_name.name, dentry->d_name.name);
 174 outrel:
 175         ncp_inode_close(inode);
 176         return already_read ? already_read : error;
 177 }
 178
 179 static ssize_t
 180 ncp_file_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
 181 {
 182         struct dentry *dentry = file->f_path.dentry;
 183         struct inode *inode = dentry->d_inode;
 184         size_t already_written = 0;
 185         off_t pos;
 186         size_t bufsize;
 187         int errno;
 188         void* bouncebuffer;
 189
 190         DPRINTK("ncp_file_write: enter %s/%s\n",
 191                 dentry->d_parent->d_name.name, dentry->d_name.name);
 192         if ((ssize_t) count < 0)
 193                 return -EINVAL;
 194         pos = *ppos;
 195         if (file->f_flags & O_APPEND) {
 196                 pos = i_size_read(inode);
 197         }
 198
 199         if (pos + count > MAX_NON_LFS && !(file->f_flags&O_LARGEFILE)) {
 200                 if (pos >= MAX_NON_LFS) {
 201                         return -EFBIG;
 202                 }
 203                 if (count > MAX_NON_LFS - (u32)pos) {
 204                         count = MAX_NON_LFS - (u32)pos;
 205                 }
 206         }
 207         if (pos >= inode->i_sb->s_maxbytes) {
 208                 if (count || pos > inode->i_sb->s_maxbytes) {
 209                         return -EFBIG;
 210                 }
 211         }
 212         if (pos + count > inode->i_sb->s_maxbytes) {
 213                 count = inode->i_sb->s_maxbytes - pos;
 214         }
 215
 216         if (!count)
 217                 return 0;
 218         errno = ncp_make_open(inode, O_WRONLY);
 219         if (errno) {
 220                 DPRINTK(KERN_ERR "ncp_file_write: open failed, error=%d\n", errno);
 221                 return errno;
 222         }
 223         bufsize = NCP_SERVER(inode)->buffer_size;
 224
 225         already_written = 0;
 226
 227         bouncebuffer = vmalloc(bufsize);
 228         if (!bouncebuffer) {
 229                 errno = -EIO;   /* -ENOMEM */
 230                 goto outrel;
 231         }
 232         while (already_written < count) {
 233                 int written_this_time;
 234                 size_t to_write = min_t(unsigned int,
 235                                       bufsize - (pos % bufsize),
 236                                       count - already_written);
 237
 238                 if (copy_from_user(bouncebuffer, buf, to_write)) {
 239                         errno = -EFAULT;
 240                         break;
 241                 }
 242                 if (ncp_write_kernel(NCP_SERVER(inode),
 243                     NCP_FINFO(inode)->file_handle,
 244                     pos, to_write, bouncebuffer, &written_this_time) != 0) {
 245                         errno = -EIO;
 246                         break;
 247                 }
 248                 pos += written_this_time;
 249                 buf += written_this_time;
 250                 already_written += written_this_time;
 251
 252                 if (written_this_time != to_write) {
 253                         break;
 254                 }
 255         }
 256         vfree(bouncebuffer);
 257
 258         file_update_time(file);
 259
 260         *ppos = pos;
 261
 262         if (pos > i_size_read(inode)) {
 263                 mutex_lock(&inode->i_mutex);
 264                 if (pos > i_size_read(inode))
 265                         i_size_write(inode, pos);
 266                 mutex_unlock(&inode->i_mutex);
 267         }
 268         DPRINTK("ncp_file_write: exit %s/%s\n",
 269                 dentry->d_parent->d_name.name, dentry->d_name.name);
 270 outrel:
 271         ncp_inode_close(inode);
 272         return already_written ? already_written : errno;
 273 }
 274
 275 static int ncp_release(struct inode *inode, struct file *file) {
 276         if (ncp_make_closed(inode)) {
 277                 DPRINTK("ncp_release: failed to close\n");
 278         }
 279         return 0;
 280 }
 281
 282 const struct file_operations ncp_file_operations =
 283 {
 284         .llseek         = generic_file_llseek,
 285         .read           = ncp_file_read,
 286         .write          = ncp_file_write,
 287         .unlocked_ioctl = ncp_ioctl,
 288 #ifdef CONFIG_COMPAT
 289         .compat_ioctl   = ncp_compat_ioctl,
 290 #endif
 291         .mmap           = ncp_mmap,
 292         .release        = ncp_release,
 293         .fsync          = ncp_fsync,
 294 };
 295
 296 const struct inode_operations ncp_file_inode_operations =
 297 {
 298         .setattr        = ncp_notify_change,
 299 };