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