* regular file handling primitives for fat-based filesystems
*/
+#include <linux/capability.h>
#include <linux/module.h>
#include <linux/time.h>
#include <linux/msdos_fs.h>
#include <linux/smp_lock.h>
#include <linux/buffer_head.h>
+#include <linux/writeback.h>
+#include <linux/backing-dev.h>
+#include <linux/blkdev.h>
-static ssize_t fat_file_write(struct file *filp, const char __user *buf,
- size_t count, loff_t *ppos)
+int fat_generic_ioctl(struct inode *inode, struct file *filp,
+ unsigned int cmd, unsigned long arg)
{
- struct inode *inode = filp->f_dentry->d_inode;
- int retval;
+ struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
+ u32 __user *user_attr = (u32 __user *)arg;
+
+ switch (cmd) {
+ case FAT_IOCTL_GET_ATTRIBUTES:
+ {
+ u32 attr;
+
+ if (inode->i_ino == MSDOS_ROOT_INO)
+ attr = ATTR_DIR;
+ else
+ attr = fat_attr(inode);
+
+ return put_user(attr, user_attr);
+ }
+ case FAT_IOCTL_SET_ATTRIBUTES:
+ {
+ u32 attr, oldattr;
+ int err, is_dir = S_ISDIR(inode->i_mode);
+ struct iattr ia;
+
+ err = get_user(attr, user_attr);
+ if (err)
+ return err;
+
+ mutex_lock(&inode->i_mutex);
+
+ if (IS_RDONLY(inode)) {
+ err = -EROFS;
+ goto up;
+ }
+
+ /*
+ * ATTR_VOLUME and ATTR_DIR cannot be changed; this also
+ * prevents the user from turning us into a VFAT
+ * longname entry. Also, we obviously can't set
+ * any of the NTFS attributes in the high 24 bits.
+ */
+ attr &= 0xff & ~(ATTR_VOLUME | ATTR_DIR);
+ /* Merge in ATTR_VOLUME and ATTR_DIR */
+ attr |= (MSDOS_I(inode)->i_attrs & ATTR_VOLUME) |
+ (is_dir ? ATTR_DIR : 0);
+ oldattr = fat_attr(inode);
+
+ /* Equivalent to a chmod() */
+ ia.ia_valid = ATTR_MODE | ATTR_CTIME;
+ if (is_dir) {
+ ia.ia_mode = MSDOS_MKMODE(attr,
+ S_IRWXUGO & ~sbi->options.fs_dmask)
+ | S_IFDIR;
+ } else {
+ ia.ia_mode = MSDOS_MKMODE(attr,
+ (S_IRUGO | S_IWUGO | (inode->i_mode & S_IXUGO))
+ & ~sbi->options.fs_fmask)
+ | S_IFREG;
+ }
+
+ /* The root directory has no attributes */
+ if (inode->i_ino == MSDOS_ROOT_INO && attr != ATTR_DIR) {
+ err = -EINVAL;
+ goto up;
+ }
+
+ if (sbi->options.sys_immutable) {
+ if ((attr | oldattr) & ATTR_SYS) {
+ if (!capable(CAP_LINUX_IMMUTABLE)) {
+ err = -EPERM;
+ goto up;
+ }
+ }
+ }
- retval = generic_file_write(filp, buf, count, ppos);
- if (retval > 0) {
- inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
- MSDOS_I(inode)->i_attrs |= ATTR_ARCH;
+ /* This MUST be done before doing anything irreversible... */
+ err = notify_change(filp->f_path.dentry, &ia);
+ if (err)
+ goto up;
+
+ if (sbi->options.sys_immutable) {
+ if (attr & ATTR_SYS)
+ inode->i_flags |= S_IMMUTABLE;
+ else
+ inode->i_flags &= S_IMMUTABLE;
+ }
+
+ MSDOS_I(inode)->i_attrs = attr & ATTR_UNUSED;
mark_inode_dirty(inode);
+ up:
+ mutex_unlock(&inode->i_mutex);
+ return err;
+ }
+ default:
+ return -ENOTTY; /* Inappropriate ioctl for device */
+ }
+}
+
+static int fat_file_release(struct inode *inode, struct file *filp)
+{
+ if ((filp->f_mode & FMODE_WRITE) &&
+ MSDOS_SB(inode->i_sb)->options.flush) {
+ fat_flush_inodes(inode->i_sb, inode, NULL);
+ congestion_wait(WRITE, HZ/10);
}
- return retval;
+ return 0;
}
-struct file_operations fat_file_operations = {
+const struct file_operations fat_file_operations = {
.llseek = generic_file_llseek,
- .read = generic_file_read,
- .write = fat_file_write,
+ .read = do_sync_read,
+ .write = do_sync_write,
+ .aio_read = generic_file_aio_read,
+ .aio_write = generic_file_aio_write,
.mmap = generic_file_mmap,
+ .release = fat_file_release,
+ .ioctl = fat_generic_ioctl,
.fsync = file_fsync,
- .readv = generic_file_readv,
- .writev = generic_file_writev,
.sendfile = generic_file_sendfile,
};
+static int fat_cont_expand(struct inode *inode, loff_t size)
+{
+ struct address_space *mapping = inode->i_mapping;
+ loff_t start = inode->i_size, count = size - inode->i_size;
+ int err;
+
+ err = generic_cont_expand_simple(inode, size);
+ if (err)
+ goto out;
+
+ inode->i_ctime = inode->i_mtime = CURRENT_TIME_SEC;
+ mark_inode_dirty(inode);
+ if (IS_SYNC(inode))
+ err = sync_page_range_nolock(inode, mapping, start, count);
+out:
+ return err;
+}
+
int fat_notify_change(struct dentry *dentry, struct iattr *attr)
{
struct msdos_sb_info *sbi = MSDOS_SB(dentry->d_sb);
lock_kernel();
- /* FAT cannot truncate to a longer file */
+ /*
+ * Expand the file. Since inode_setattr() updates ->i_size
+ * before calling the ->truncate(), but FAT needs to fill the
+ * hole before it.
+ */
if (attr->ia_valid & ATTR_SIZE) {
if (attr->ia_size > inode->i_size) {
- error = -EPERM;
- goto out;
+ error = fat_cont_expand(inode, attr->ia_size);
+ if (error || attr->ia_valid == ATTR_SIZE)
+ goto out;
+ attr->ia_valid &= ~ATTR_SIZE;
}
}
return error;
}
-EXPORT_SYMBOL(fat_notify_change);
+EXPORT_SYMBOL_GPL(fat_notify_change);
/* Free all clusters after the skip'th cluster. */
static int fat_free(struct inode *inode, int skip)
{
struct super_block *sb = inode->i_sb;
- int nr, ret, fclus, dclus;
+ int err, wait, free_start, i_start, i_logstart;
if (MSDOS_I(inode)->i_start == 0)
return 0;
+ fat_cache_inval_inode(inode);
+
+ wait = IS_DIRSYNC(inode);
+ i_start = free_start = MSDOS_I(inode)->i_start;
+ i_logstart = MSDOS_I(inode)->i_logstart;
+
+ /* First, we write the new file size. */
+ if (!skip) {
+ MSDOS_I(inode)->i_start = 0;
+ MSDOS_I(inode)->i_logstart = 0;
+ }
+ MSDOS_I(inode)->i_attrs |= ATTR_ARCH;
+ inode->i_ctime = inode->i_mtime = CURRENT_TIME_SEC;
+ if (wait) {
+ err = fat_sync_inode(inode);
+ if (err) {
+ MSDOS_I(inode)->i_start = i_start;
+ MSDOS_I(inode)->i_logstart = i_logstart;
+ return err;
+ }
+ } else
+ mark_inode_dirty(inode);
+
+ /* Write a new EOF, and get the remaining cluster chain for freeing. */
if (skip) {
+ struct fat_entry fatent;
+ int ret, fclus, dclus;
+
ret = fat_get_cluster(inode, skip - 1, &fclus, &dclus);
if (ret < 0)
return ret;
else if (ret == FAT_ENT_EOF)
return 0;
- nr = fat_access(sb, dclus, -1);
- if (nr == FAT_ENT_EOF)
+ fatent_init(&fatent);
+ ret = fat_ent_read(inode, &fatent, dclus);
+ if (ret == FAT_ENT_EOF) {
+ fatent_brelse(&fatent);
return 0;
- else if (nr > 0) {
- /*
- * write a new EOF, and get the remaining cluster
- * chain for freeing.
- */
- nr = fat_access(sb, dclus, FAT_ENT_EOF);
+ } else if (ret == FAT_ENT_FREE) {
+ fat_fs_panic(sb,
+ "%s: invalid cluster chain (i_pos %lld)",
+ __FUNCTION__, MSDOS_I(inode)->i_pos);
+ ret = -EIO;
+ } else if (ret > 0) {
+ err = fat_ent_write(inode, &fatent, FAT_ENT_EOF, wait);
+ if (err)
+ ret = err;
}
- if (nr < 0)
- return nr;
-
- fat_cache_inval_inode(inode);
- } else {
- fat_cache_inval_inode(inode);
+ fatent_brelse(&fatent);
+ if (ret < 0)
+ return ret;
- nr = MSDOS_I(inode)->i_start;
- MSDOS_I(inode)->i_start = 0;
- MSDOS_I(inode)->i_logstart = 0;
- mark_inode_dirty(inode);
+ free_start = ret;
}
+ inode->i_blocks = skip << (MSDOS_SB(sb)->cluster_bits - 9);
- lock_fat(sb);
- do {
- nr = fat_access(sb, nr, FAT_ENT_FREE);
- if (nr < 0)
- goto error;
- else if (nr == FAT_ENT_FREE) {
- fat_fs_panic(sb, "%s: deleting beyond EOF (i_pos %lld)",
- __FUNCTION__, MSDOS_I(inode)->i_pos);
- nr = -EIO;
- goto error;
- }
- if (MSDOS_SB(sb)->free_clusters != -1)
- MSDOS_SB(sb)->free_clusters++;
- inode->i_blocks -= MSDOS_SB(sb)->cluster_size >> 9;
- } while (nr != FAT_ENT_EOF);
- fat_clusters_flush(sb);
- nr = 0;
-error:
- unlock_fat(sb);
-
- return nr;
+ /* Freeing the remained cluster chain */
+ return fat_free_clusters(inode, free_start);
}
void fat_truncate(struct inode *inode)
lock_kernel();
fat_free(inode, nr_clusters);
- MSDOS_I(inode)->i_attrs |= ATTR_ARCH;
unlock_kernel();
- inode->i_ctime = inode->i_mtime = CURRENT_TIME_SEC;
- mark_inode_dirty(inode);
+ fat_flush_inodes(inode->i_sb, inode, NULL);
+}
+
+int fat_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
+{
+ struct inode *inode = dentry->d_inode;
+ generic_fillattr(inode, stat);
+ stat->blksize = MSDOS_SB(inode->i_sb)->cluster_size;
+ return 0;
}
+EXPORT_SYMBOL_GPL(fat_getattr);
struct inode_operations fat_file_inode_operations = {
.truncate = fat_truncate,
.setattr = fat_notify_change,
+ .getattr = fat_getattr,
};