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/smp_lock.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         down(&NCP_FINFO(inode)->open_sem);
  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         up(&NCP_FINFO(inode)->open_sem);
  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_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         if (!S_ISREG(inode->i_mode)) {
 119                 DPRINTK("ncp_file_read: read from non-file, mode %07o\n",
 120                         inode->i_mode);
 121                 return -EINVAL;
 122         }
 123
 124         pos = *ppos;
 125
 126         if ((ssize_t) count < 0) {
 127                 return -EINVAL;
 128         }
 129         if (!count)
 130                 return 0;
 131         if (pos > inode->i_sb->s_maxbytes)
 132                 return 0;
 133         if (pos + count > inode->i_sb->s_maxbytes) {
 134                 count = inode->i_sb->s_maxbytes - pos;
 135         }
 136
 137         error = ncp_make_open(inode, O_RDONLY);
 138         if (error) {
 139                 DPRINTK(KERN_ERR "ncp_file_read: open failed, error=%d\n", error);
 140                 return error;
 141         }
 142
 143         bufsize = NCP_SERVER(inode)->buffer_size;
 144
 145         error = -EIO;
 146         freelen = ncp_read_bounce_size(bufsize);
 147         freepage = vmalloc(freelen);
 148         if (!freepage)
 149                 goto outrel;
 150         error = 0;
 151         /* First read in as much as possible for each bufsize. */
 152         while (already_read < count) {
 153                 int read_this_time;
 154                 size_t to_read = min_t(unsigned int,
 155                                      bufsize - (pos % bufsize),
 156                                      count - already_read);
 157
 158                 error = ncp_read_bounce(NCP_SERVER(inode),
 159                                 NCP_FINFO(inode)->file_handle,
 160                                 pos, to_read, buf, &read_this_time,
 161                                 freepage, freelen);
 162                 if (error) {
 163                         error = -EIO;   /* NW errno -> Linux errno */
 164                         break;
 165                 }
 166                 pos += read_this_time;
 167                 buf += read_this_time;
 168                 already_read += read_this_time;
 169
 170                 if (read_this_time != to_read) {
 171                         break;
 172                 }
 173         }
 174         vfree(freepage);
 175
 176         *ppos = pos;
 177
 178         if (!IS_RDONLY(inode)) {
 179                 inode->i_atime = CURRENT_TIME;
 180         }
 181
 182         DPRINTK("ncp_file_read: exit %s/%s\n",
 183                 dentry->d_parent->d_name.name, dentry->d_name.name);
 184 outrel:
 185         ncp_inode_close(inode);
 186         return already_read ? already_read : error;
 187 }
 188
 189 static ssize_t
 190 ncp_file_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
 191 {
 192         struct dentry *dentry = file->f_dentry;
 193         struct inode *inode = dentry->d_inode;
 194         size_t already_written = 0;
 195         off_t pos;
 196         size_t bufsize;
 197         int errno;
 198         void* bouncebuffer;
 199
 200         DPRINTK("ncp_file_write: enter %s/%s\n",
 201                 dentry->d_parent->d_name.name, dentry->d_name.name);
 202         if (!ncp_conn_valid(NCP_SERVER(inode)))
 203                 return -EIO;
 204         if (!S_ISREG(inode->i_mode)) {
 205                 DPRINTK("ncp_file_write: write to non-file, mode %07o\n",
 206                         inode->i_mode);
 207                 return -EINVAL;
 208         }
 209         if ((ssize_t) count < 0)
 210                 return -EINVAL;
 211         pos = *ppos;
 212         if (file->f_flags & O_APPEND) {
 213                 pos = inode->i_size;
 214         }
 215
 216         if (pos + count > MAX_NON_LFS && !(file->f_flags&O_LARGEFILE)) {
 217                 if (pos >= MAX_NON_LFS) {
 218                         send_sig(SIGXFSZ, current, 0);
 219                         return -EFBIG;
 220                 }
 221                 if (count > MAX_NON_LFS - (u32)pos) {
 222                         count = MAX_NON_LFS - (u32)pos;
 223                 }
 224         }
 225         if (pos >= inode->i_sb->s_maxbytes) {
 226                 if (count || pos > inode->i_sb->s_maxbytes) {
 227                         send_sig(SIGXFSZ, current, 0);
 228                         return -EFBIG;
 229                 }
 230         }
 231         if (pos + count > inode->i_sb->s_maxbytes) {
 232                 count = inode->i_sb->s_maxbytes - pos;
 233         }
 234
 235         if (!count)
 236                 return 0;
 237         errno = ncp_make_open(inode, O_WRONLY);
 238         if (errno) {
 239                 DPRINTK(KERN_ERR "ncp_file_write: open failed, error=%d\n", errno);
 240                 return errno;
 241         }
 242         bufsize = NCP_SERVER(inode)->buffer_size;
 243
 244         already_written = 0;
 245
 246         bouncebuffer = vmalloc(bufsize);
 247         if (!bouncebuffer) {
 248                 errno = -EIO;   /* -ENOMEM */
 249                 goto outrel;
 250         }
 251         while (already_written < count) {
 252                 int written_this_time;
 253                 size_t to_write = min_t(unsigned int,
 254                                       bufsize - (pos % bufsize),
 255                                       count - already_written);
 256
 257                 if (copy_from_user(bouncebuffer, buf, to_write)) {
 258                         errno = -EFAULT;
 259                         break;
 260                 }
 261                 if (ncp_write_kernel(NCP_SERVER(inode),
 262                     NCP_FINFO(inode)->file_handle,
 263                     pos, to_write, bouncebuffer, &written_this_time) != 0) {
 264                         errno = -EIO;
 265                         break;
 266                 }
 267                 pos += written_this_time;
 268                 buf += written_this_time;
 269                 already_written += written_this_time;
 270
 271                 if (written_this_time != to_write) {
 272                         break;
 273                 }
 274         }
 275         vfree(bouncebuffer);
 276         inode->i_mtime = inode->i_atime = CURRENT_TIME;
 277
 278         *ppos = pos;
 279
 280         if (pos > inode->i_size) {
 281                 inode->i_size = pos;
 282         }
 283         DPRINTK("ncp_file_write: exit %s/%s\n",
 284                 dentry->d_parent->d_name.name, dentry->d_name.name);
 285 outrel:
 286         ncp_inode_close(inode);
 287         return already_written ? already_written : errno;
 288 }
 289
 290 static int ncp_release(struct inode *inode, struct file *file) {
 291         if (ncp_make_closed(inode)) {
 292                 DPRINTK("ncp_release: failed to close\n");
 293         }
 294         return 0;
 295 }
 296
 297 struct file_operations ncp_file_operations =
 298 {
 299         .llseek         = remote_llseek,
 300         .read           = ncp_file_read,
 301         .write          = ncp_file_write,
 302         .ioctl          = ncp_ioctl,
 303         .mmap           = ncp_mmap,
 304         .release        = ncp_release,
 305         .fsync          = ncp_fsync,
 306 };
 307
 308 struct inode_operations ncp_file_inode_operations =
 309 {
 310         .setattr        = ncp_notify_change,
 311 };