X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=fs%2Ffat%2Ffile.c;h=c1237b70c1fee7c11f06182f67d20b5a9f6a700f;hb=refs%2Fheads%2Fvserver;hp=ba1707a5ce3e973db3147818a24f7a0aef15cc84;hpb=9213980e6a70d8473e0ffd4b39ab5b6caaba9ff5;p=linux-2.6.git

diff --git a/fs/fat/file.c b/fs/fat/file.c
index ba1707a5c..c1237b70c 100644
--- a/fs/fat/file.c
+++ b/fs/fat/file.c
@@ -6,82 +6,280 @@
  *  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 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;
+				}
+			}
+		}
+
+		/* 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 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,
 };
 
-struct inode_operations fat_file_inode_operations = {
-	.truncate	= fat_truncate,
-	.setattr	= fat_notify_change,
-};
-
-int fat_get_block(struct inode *inode, sector_t iblock,
-		  struct buffer_head *bh_result, int create)
+static int fat_cont_expand(struct inode *inode, loff_t size)
 {
-	struct super_block *sb = inode->i_sb;
-	sector_t phys;
+	struct address_space *mapping = inode->i_mapping;
+	loff_t start = inode->i_size, count = size - inode->i_size;
 	int err;
 
-	err = fat_bmap(inode, iblock, &phys);
+	err = generic_cont_expand_simple(inode, size);
 	if (err)
-		return err;
-	if (phys) {
-		map_bh(bh_result, sb, phys);
-		return 0;
+		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);
+	struct inode *inode = dentry->d_inode;
+	int mask, error = 0;
+
+	lock_kernel();
+
+	/*
+	 * 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 = fat_cont_expand(inode, attr->ia_size);
+			if (error || attr->ia_valid == ATTR_SIZE)
+				goto out;
+			attr->ia_valid &= ~ATTR_SIZE;
+		}
 	}
-	if (!create)
-		return 0;
-	if (iblock != MSDOS_I(inode)->mmu_private >> sb->s_blocksize_bits) {
-		fat_fs_panic(sb, "corrupted file size (i_pos %lld, %lld)",
-			     MSDOS_I(inode)->i_pos, MSDOS_I(inode)->mmu_private);
-		return -EIO;
+
+	error = inode_change_ok(inode, attr);
+	if (error) {
+		if (sbi->options.quiet)
+			error = 0;
+		goto out;
 	}
-	if (!((unsigned long)iblock & (MSDOS_SB(sb)->sec_per_clus - 1))) {
-		int error;
+	if (((attr->ia_valid & ATTR_UID) &&
+	     (attr->ia_uid != sbi->options.fs_uid)) ||
+	    ((attr->ia_valid & ATTR_GID) &&
+	     (attr->ia_gid != sbi->options.fs_gid)) ||
+	    ((attr->ia_valid & ATTR_MODE) &&
+	     (attr->ia_mode & ~MSDOS_VALID_MODE)))
+		error = -EPERM;
 
-		error = fat_add_cluster(inode);
-		if (error < 0)
-			return error;
+	if (error) {
+		if (sbi->options.quiet)
+			error = 0;
+		goto out;
 	}
-	MSDOS_I(inode)->mmu_private += sb->s_blocksize;
-	err = fat_bmap(inode, iblock, &phys);
-	if (err)
-		return err;
-	if (!phys)
-		BUG();
-	set_buffer_new(bh_result);
-	map_bh(bh_result, sb, phys);
-	return 0;
+	error = inode_setattr(inode, attr);
+	if (error)
+		goto out;
+
+	if (S_ISDIR(inode->i_mode))
+		mask = sbi->options.fs_dmask;
+	else
+		mask = sbi->options.fs_fmask;
+	inode->i_mode &= S_IFMT | (S_IRWXUGO & ~mask);
+out:
+	unlock_kernel();
+	return error;
 }
 
-static ssize_t fat_file_write(struct file *filp, const char __user *buf,
-			      size_t count, loff_t *ppos)
+EXPORT_SYMBOL_GPL(fat_notify_change);
+
+/* Free all clusters after the skip'th cluster. */
+static int fat_free(struct inode *inode, int skip)
 {
-	struct inode *inode = filp->f_dentry->d_inode;
-	int retval;
+	struct super_block *sb = inode->i_sb;
+	int err, wait, free_start, i_start, i_logstart;
 
-	retval = generic_file_write(filp, buf, count, ppos);
-	if (retval > 0) {
-		inode->i_mtime = inode->i_ctime = CURRENT_TIME;
-		MSDOS_I(inode)->i_attrs |= ATTR_ARCH;
+	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;
+
+		fatent_init(&fatent);
+		ret = fat_ent_read(inode, &fatent, dclus);
+		if (ret == FAT_ENT_EOF) {
+			fatent_brelse(&fatent);
+			return 0;
+		} 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;
+		}
+		fatent_brelse(&fatent);
+		if (ret < 0)
+			return ret;
+
+		free_start = ret;
 	}
-	return retval;
+	inode->i_blocks = skip << (MSDOS_SB(sb)->cluster_bits - 9);
+
+	/* Freeing the remained cluster chain */
+	return fat_free_clusters(inode, free_start);
 }
 
 void fat_truncate(struct inode *inode)
@@ -90,13 +288,7 @@ void fat_truncate(struct inode *inode)
 	const unsigned int cluster_size = sbi->cluster_size;
 	int nr_clusters;
 
-	/* Why no return value?  Surely the disk could fail... */
-	if (IS_RDONLY (inode))
-		return /* -EPERM */;
-	if (IS_IMMUTABLE(inode))
-		return /* -EPERM */;
-
-	/* 
+	/*
 	 * This protects against truncating a file bigger than it was then
 	 * trying to write into the hole.
 	 */
@@ -107,8 +299,21 @@ 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;
-	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,
+};