fs/reiserfs/dir.c - kernel/msm-4.9 - Gitiles

 /*
  * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
  */

 #include <linux/config.h>
 #include <linux/string.h>
 #include <linux/errno.h>
 #include <linux/fs.h>
 #include <linux/reiserfs_fs.h>
 #include <linux/stat.h>
 #include <linux/smp_lock.h>
 #include <linux/buffer_head.h>
 #include <asm/uaccess.h>

 extern struct reiserfs_key  MIN_KEY;

 static int reiserfs_readdir (struct file *, void *, filldir_t);
 static int reiserfs_dir_fsync(struct file *filp, struct dentry *dentry, int datasync) ;

 struct file_operations reiserfs_dir_operations = {
     .read	= generic_read_dir,
     .readdir	= reiserfs_readdir,
     .fsync	= reiserfs_dir_fsync,
     .ioctl	= reiserfs_ioctl,
 };

 static int reiserfs_dir_fsync(struct file *filp, struct dentry *dentry, int datasync) {
   struct inode *inode = dentry->d_inode;
   int err;
   reiserfs_write_lock(inode->i_sb);
   err = reiserfs_commit_for_inode(inode) ;
   reiserfs_write_unlock(inode->i_sb) ;
   if (err < 0)
       return err;
   return 0;
 }


 #define store_ih(where,what) copy_item_head (where, what)

 //
 static int reiserfs_readdir (struct file * filp, void * dirent, filldir_t filldir)
 {
     struct inode *inode = filp->f_dentry->d_inode;
     struct cpu_key pos_key;	/* key of current position in the directory (key of directory entry) */
     INITIALIZE_PATH (path_to_entry);
     struct buffer_head * bh;
     int item_num, entry_num;
     const struct reiserfs_key * rkey;
     struct item_head * ih, tmp_ih;
     int search_res;
     char * local_buf;
     loff_t next_pos;
     char small_buf[32] ; /* avoid kmalloc if we can */
     struct reiserfs_dir_entry de;
     int ret = 0;

     reiserfs_write_lock(inode->i_sb);

     reiserfs_check_lock_depth(inode->i_sb, "readdir") ;

     /* form key for search the next directory entry using f_pos field of
        file structure */
     make_cpu_key (&pos_key, inode, (filp->f_pos) ? (filp->f_pos) : DOT_OFFSET,
 		  TYPE_DIRENTRY, 3);
     next_pos = cpu_key_k_offset (&pos_key);

     /*  reiserfs_warning (inode->i_sb, "reiserfs_readdir 1: f_pos = %Ld", filp->f_pos);*/

     path_to_entry.reada = PATH_READA;
     while (1) {
     research:
 	/* search the directory item, containing entry with specified key */
 	search_res = search_by_entry_key (inode->i_sb, &pos_key, &path_to_entry, &de);
 	if (search_res == IO_ERROR) {
 	    // FIXME: we could just skip part of directory which could
 	    // not be read
 	    ret = -EIO;
 	    goto out;
 	}
 	entry_num = de.de_entry_num;
 	bh = de.de_bh;
 	item_num = de.de_item_num;
 	ih = de.de_ih;
 	store_ih (&tmp_ih, ih);

 	/* we must have found item, that is item of this directory, */
 	RFALSE( COMP_SHORT_KEYS (&(ih->ih_key), &pos_key),
 		"vs-9000: found item %h does not match to dir we readdir %K",
 		ih, &pos_key);
 	RFALSE( item_num > B_NR_ITEMS (bh) - 1,
 		"vs-9005 item_num == %d, item amount == %d",
 		item_num, B_NR_ITEMS (bh));

 	/* and entry must be not more than number of entries in the item */
 	RFALSE( I_ENTRY_COUNT (ih) < entry_num,
 		"vs-9010: entry number is too big %d (%d)",
 		entry_num, I_ENTRY_COUNT (ih));

 	if (search_res == POSITION_FOUND || entry_num < I_ENTRY_COUNT (ih)) {
 	    /* go through all entries in the directory item beginning from the entry, that has been found */
 	    struct reiserfs_de_head * deh = B_I_DEH (bh, ih) + entry_num;

 	    for (; entry_num < I_ENTRY_COUNT (ih); entry_num ++, deh ++) {
 		int d_reclen;
 		char * d_name;
 		off_t d_off;
 		ino_t d_ino;

 		if (!de_visible (deh))
 		    /* it is hidden entry */
 		    continue;
 		d_reclen = entry_length (bh, ih, entry_num);
 		d_name = B_I_DEH_ENTRY_FILE_NAME (bh, ih, deh);
 		if (!d_name[d_reclen - 1])
 		    d_reclen = strlen (d_name);

 		if (d_reclen > REISERFS_MAX_NAME(inode->i_sb->s_blocksize)){
 		    /* too big to send back to VFS */
 		    continue ;
 		}

                 /* Ignore the .reiserfs_priv entry */
                 if (reiserfs_xattrs (inode->i_sb) &&
                     !old_format_only(inode->i_sb) &&
                     filp->f_dentry == inode->i_sb->s_root &&
                     REISERFS_SB(inode->i_sb)->priv_root &&
                     REISERFS_SB(inode->i_sb)->priv_root->d_inode &&
                     deh_objectid(deh) == le32_to_cpu (INODE_PKEY(REISERFS_SB(inode->i_sb)->priv_root->d_inode)->k_objectid)) {
                   continue;
                 }

 		d_off = deh_offset (deh);
 		filp->f_pos = d_off ;
 		d_ino = deh_objectid (deh);
 		if (d_reclen <= 32) {
 		  local_buf = small_buf ;
 		} else {
 		    local_buf = reiserfs_kmalloc(d_reclen, GFP_NOFS, inode->i_sb) ;
 		    if (!local_buf) {
 			pathrelse (&path_to_entry);
 			ret = -ENOMEM ;
 			goto out;
 		    }
 		    if (item_moved (&tmp_ih, &path_to_entry)) {
 			reiserfs_kfree(local_buf, d_reclen, inode->i_sb) ;
 			goto research;
 		    }
 		}
 		// Note, that we copy name to user space via temporary
 		// buffer (local_buf) because filldir will block if
 		// user space buffer is swapped out. At that time
 		// entry can move to somewhere else
 		memcpy (local_buf, d_name, d_reclen);
 		if (filldir (dirent, local_buf, d_reclen, d_off, d_ino,
 		             DT_UNKNOWN) < 0) {
 		    if (local_buf != small_buf) {
 			reiserfs_kfree(local_buf, d_reclen, inode->i_sb) ;
 		    }
 		    goto end;
 		}
 		if (local_buf != small_buf) {
 		    reiserfs_kfree(local_buf, d_reclen, inode->i_sb) ;
 		}

 		// next entry should be looked for with such offset
 		next_pos = deh_offset (deh) + 1;

 		if (item_moved (&tmp_ih, &path_to_entry)) {
 		    goto research;
 		}
 	    } /* for */
 	}

 	if (item_num != B_NR_ITEMS (bh) - 1)
 	    // end of directory has been reached
 	    goto end;

 	/* item we went through is last item of node. Using right
 	   delimiting key check is it directory end */
 	rkey = get_rkey (&path_to_entry, inode->i_sb);
 	if (! comp_le_keys (rkey, &MIN_KEY)) {
 	    /* set pos_key to key, that is the smallest and greater
 	       that key of the last entry in the item */
 	    set_cpu_key_k_offset (&pos_key, next_pos);
 	    continue;
 	}

 	if ( COMP_SHORT_KEYS (rkey, &pos_key)) {
 	    // end of directory has been reached
 	    goto end;
 	}

 	/* directory continues in the right neighboring block */
 	set_cpu_key_k_offset (&pos_key, le_key_k_offset (KEY_FORMAT_3_5, rkey));

     } /* while */


  end:
     filp->f_pos = next_pos;
     pathrelse (&path_to_entry);
     reiserfs_check_path(&path_to_entry) ;
  out:
     reiserfs_write_unlock(inode->i_sb);
     return ret;
 }

 /* compose directory item containing "." and ".." entries (entries are
    not aligned to 4 byte boundary) */
 /* the last four params are LE */
 void make_empty_dir_item_v1 (char * body, __u32 dirid, __u32 objid,
 			     __u32 par_dirid, __u32 par_objid)
 {
     struct reiserfs_de_head * deh;

     memset (body, 0, EMPTY_DIR_SIZE_V1);
     deh = (struct reiserfs_de_head *)body;

     /* direntry header of "." */
     put_deh_offset( &(deh[0]), DOT_OFFSET );
     /* these two are from make_le_item_head, and are are LE */
     deh[0].deh_dir_id = dirid;
     deh[0].deh_objectid = objid;
     deh[0].deh_state = 0; /* Endian safe if 0 */
     put_deh_location( &(deh[0]), EMPTY_DIR_SIZE_V1 - strlen( "." ));
     mark_de_visible(&(deh[0]));

     /* direntry header of ".." */
     put_deh_offset( &(deh[1]), DOT_DOT_OFFSET);
     /* key of ".." for the root directory */
     /* these two are from the inode, and are are LE */
     deh[1].deh_dir_id = par_dirid;
     deh[1].deh_objectid = par_objid;
     deh[1].deh_state = 0; /* Endian safe if 0 */
     put_deh_location( &(deh[1]), deh_location( &(deh[0]) ) - strlen( ".." ) );
     mark_de_visible(&(deh[1]));

     /* copy ".." and "." */
     memcpy (body + deh_location( &(deh[0]) ), ".", 1);
     memcpy (body + deh_location( &(deh[1]) ), "..", 2);
 }

 /* compose directory item containing "." and ".." entries */
 void make_empty_dir_item (char * body, __u32 dirid, __u32 objid,
 			  __u32 par_dirid, __u32 par_objid)
 {
     struct reiserfs_de_head * deh;

     memset (body, 0, EMPTY_DIR_SIZE);
     deh = (struct reiserfs_de_head *)body;

     /* direntry header of "." */
     put_deh_offset( &(deh[0]), DOT_OFFSET );
     /* these two are from make_le_item_head, and are are LE */
     deh[0].deh_dir_id = dirid;
     deh[0].deh_objectid = objid;
     deh[0].deh_state = 0; /* Endian safe if 0 */
     put_deh_location( &(deh[0]), EMPTY_DIR_SIZE - ROUND_UP( strlen( "." ) ) );
     mark_de_visible(&(deh[0]));

     /* direntry header of ".." */
     put_deh_offset( &(deh[1]), DOT_DOT_OFFSET );
     /* key of ".." for the root directory */
     /* these two are from the inode, and are are LE */
     deh[1].deh_dir_id = par_dirid;
     deh[1].deh_objectid = par_objid;
     deh[1].deh_state = 0; /* Endian safe if 0 */
     put_deh_location( &(deh[1]), deh_location( &(deh[0])) - ROUND_UP( strlen( ".." ) ) );
     mark_de_visible(&(deh[1]));

     /* copy ".." and "." */
     memcpy (body + deh_location( &(deh[0]) ), ".", 1);
     memcpy (body + deh_location( &(deh[1]) ), "..", 2);
 }
	/*
	* Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
	*/

	#include <linux/config.h>
	#include <linux/string.h>
	#include <linux/errno.h>
	#include <linux/fs.h>
	#include <linux/reiserfs_fs.h>
	#include <linux/stat.h>
	#include <linux/smp_lock.h>
	#include <linux/buffer_head.h>
	#include <asm/uaccess.h>

	extern struct reiserfs_key MIN_KEY;

	static int reiserfs_readdir (struct file , void , filldir_t);
	static int reiserfs_dir_fsync(struct file filp, struct dentry dentry, int datasync) ;

	struct file_operations reiserfs_dir_operations = {
	.read = generic_read_dir,
	.readdir = reiserfs_readdir,
	.fsync = reiserfs_dir_fsync,
	.ioctl = reiserfs_ioctl,
	};

	static int reiserfs_dir_fsync(struct file filp, struct dentry dentry, int datasync) {
	struct inode *inode = dentry->d_inode;
	int err;
	reiserfs_write_lock(inode->i_sb);
	err = reiserfs_commit_for_inode(inode) ;
	reiserfs_write_unlock(inode->i_sb) ;
	if (err < 0)
	return err;
	return 0;
	}


	#define store_ih(where,what) copy_item_head (where, what)

	//
	static int reiserfs_readdir (struct file * filp, void * dirent, filldir_t filldir)
	{
	struct inode *inode = filp->f_dentry->d_inode;
	struct cpu_key pos_key; /* key of current position in the directory (key of directory entry) */
	INITIALIZE_PATH (path_to_entry);
	struct buffer_head * bh;
	int item_num, entry_num;
	const struct reiserfs_key * rkey;
	struct item_head * ih, tmp_ih;
	int search_res;
	char * local_buf;
	loff_t next_pos;
	char small_buf[32] ; /* avoid kmalloc if we can */
	struct reiserfs_dir_entry de;
	int ret = 0;

	reiserfs_write_lock(inode->i_sb);

	reiserfs_check_lock_depth(inode->i_sb, "readdir") ;

	/* form key for search the next directory entry using f_pos field of
	file structure */
	make_cpu_key (&pos_key, inode, (filp->f_pos) ? (filp->f_pos) : DOT_OFFSET,
	TYPE_DIRENTRY, 3);
	next_pos = cpu_key_k_offset (&pos_key);

	/* reiserfs_warning (inode->i_sb, "reiserfs_readdir 1: f_pos = %Ld", filp->f_pos);*/

	path_to_entry.reada = PATH_READA;
	while (1) {
	research:
	/* search the directory item, containing entry with specified key */
	search_res = search_by_entry_key (inode->i_sb, &pos_key, &path_to_entry, &de);
	if (search_res == IO_ERROR) {
	// FIXME: we could just skip part of directory which could
	// not be read
	ret = -EIO;
	goto out;
	}
	entry_num = de.de_entry_num;
	bh = de.de_bh;
	item_num = de.de_item_num;
	ih = de.de_ih;
	store_ih (&tmp_ih, ih);

	/* we must have found item, that is item of this directory, */
	RFALSE( COMP_SHORT_KEYS (&(ih->ih_key), &pos_key),
	"vs-9000: found item %h does not match to dir we readdir %K",
	ih, &pos_key);
	RFALSE( item_num > B_NR_ITEMS (bh) - 1,
	"vs-9005 item_num == %d, item amount == %d",
	item_num, B_NR_ITEMS (bh));

	/* and entry must be not more than number of entries in the item */
	RFALSE( I_ENTRY_COUNT (ih) < entry_num,
	"vs-9010: entry number is too big %d (%d)",
	entry_num, I_ENTRY_COUNT (ih));

	if (search_res == POSITION_FOUND \|\| entry_num < I_ENTRY_COUNT (ih)) {
	/* go through all entries in the directory item beginning from the entry, that has been found */
	struct reiserfs_de_head * deh = B_I_DEH (bh, ih) + entry_num;

	for (; entry_num < I_ENTRY_COUNT (ih); entry_num ++, deh ++) {
	int d_reclen;
	char * d_name;
	off_t d_off;
	ino_t d_ino;

	if (!de_visible (deh))
	/* it is hidden entry */
	continue;
	d_reclen = entry_length (bh, ih, entry_num);
	d_name = B_I_DEH_ENTRY_FILE_NAME (bh, ih, deh);
	if (!d_name[d_reclen - 1])
	d_reclen = strlen (d_name);

	if (d_reclen > REISERFS_MAX_NAME(inode->i_sb->s_blocksize)){
	/* too big to send back to VFS */
	continue ;
	}

	/* Ignore the .reiserfs_priv entry */
	if (reiserfs_xattrs (inode->i_sb) &&
	!old_format_only(inode->i_sb) &&
	filp->f_dentry == inode->i_sb->s_root &&
	REISERFS_SB(inode->i_sb)->priv_root &&
	REISERFS_SB(inode->i_sb)->priv_root->d_inode &&
	deh_objectid(deh) == le32_to_cpu (INODE_PKEY(REISERFS_SB(inode->i_sb)->priv_root->d_inode)->k_objectid)) {
	continue;
	}

	d_off = deh_offset (deh);
	filp->f_pos = d_off ;
	d_ino = deh_objectid (deh);
	if (d_reclen <= 32) {
	local_buf = small_buf ;
	} else {
	local_buf = reiserfs_kmalloc(d_reclen, GFP_NOFS, inode->i_sb) ;
	if (!local_buf) {
	pathrelse (&path_to_entry);
	ret = -ENOMEM ;
	goto out;
	}
	if (item_moved (&tmp_ih, &path_to_entry)) {
	reiserfs_kfree(local_buf, d_reclen, inode->i_sb) ;
	goto research;
	}
	}
	// Note, that we copy name to user space via temporary
	// buffer (local_buf) because filldir will block if
	// user space buffer is swapped out. At that time
	// entry can move to somewhere else
	memcpy (local_buf, d_name, d_reclen);
	if (filldir (dirent, local_buf, d_reclen, d_off, d_ino,
	DT_UNKNOWN) < 0) {
	if (local_buf != small_buf) {
	reiserfs_kfree(local_buf, d_reclen, inode->i_sb) ;
	}
	goto end;
	}
	if (local_buf != small_buf) {
	reiserfs_kfree(local_buf, d_reclen, inode->i_sb) ;
	}

	// next entry should be looked for with such offset
	next_pos = deh_offset (deh) + 1;

	if (item_moved (&tmp_ih, &path_to_entry)) {
	goto research;
	}
	} /* for */
	}

	if (item_num != B_NR_ITEMS (bh) - 1)
	// end of directory has been reached
	goto end;

	/* item we went through is last item of node. Using right
	delimiting key check is it directory end */
	rkey = get_rkey (&path_to_entry, inode->i_sb);
	if (! comp_le_keys (rkey, &MIN_KEY)) {
	/* set pos_key to key, that is the smallest and greater
	that key of the last entry in the item */
	set_cpu_key_k_offset (&pos_key, next_pos);
	continue;
	}

	if ( COMP_SHORT_KEYS (rkey, &pos_key)) {
	// end of directory has been reached
	goto end;
	}

	/* directory continues in the right neighboring block */
	set_cpu_key_k_offset (&pos_key, le_key_k_offset (KEY_FORMAT_3_5, rkey));

	} /* while */


	end:
	filp->f_pos = next_pos;
	pathrelse (&path_to_entry);
	reiserfs_check_path(&path_to_entry) ;
	out:
	reiserfs_write_unlock(inode->i_sb);
	return ret;
	}

	/* compose directory item containing "." and ".." entries (entries are
	not aligned to 4 byte boundary) */
	/* the last four params are LE */
	void make_empty_dir_item_v1 (char * body, __u32 dirid, __u32 objid,
	__u32 par_dirid, __u32 par_objid)
	{
	struct reiserfs_de_head * deh;

	memset (body, 0, EMPTY_DIR_SIZE_V1);
	deh = (struct reiserfs_de_head *)body;

	/* direntry header of "." */
	put_deh_offset( &(deh[0]), DOT_OFFSET );
	/* these two are from make_le_item_head, and are are LE */
	deh[0].deh_dir_id = dirid;
	deh[0].deh_objectid = objid;
	deh[0].deh_state = 0; /* Endian safe if 0 */
	put_deh_location( &(deh[0]), EMPTY_DIR_SIZE_V1 - strlen( "." ));
	mark_de_visible(&(deh[0]));

	/* direntry header of ".." */
	put_deh_offset( &(deh[1]), DOT_DOT_OFFSET);
	/* key of ".." for the root directory */
	/* these two are from the inode, and are are LE */
	deh[1].deh_dir_id = par_dirid;
	deh[1].deh_objectid = par_objid;
	deh[1].deh_state = 0; /* Endian safe if 0 */
	put_deh_location( &(deh[1]), deh_location( &(deh[0]) ) - strlen( ".." ) );
	mark_de_visible(&(deh[1]));

	/* copy ".." and "." */
	memcpy (body + deh_location( &(deh[0]) ), ".", 1);
	memcpy (body + deh_location( &(deh[1]) ), "..", 2);
	}

	/* compose directory item containing "." and ".." entries */
	void make_empty_dir_item (char * body, __u32 dirid, __u32 objid,
	__u32 par_dirid, __u32 par_objid)
	{
	struct reiserfs_de_head * deh;

	memset (body, 0, EMPTY_DIR_SIZE);
	deh = (struct reiserfs_de_head *)body;

	/* direntry header of "." */
	put_deh_offset( &(deh[0]), DOT_OFFSET );
	/* these two are from make_le_item_head, and are are LE */
	deh[0].deh_dir_id = dirid;
	deh[0].deh_objectid = objid;
	deh[0].deh_state = 0; /* Endian safe if 0 */
	put_deh_location( &(deh[0]), EMPTY_DIR_SIZE - ROUND_UP( strlen( "." ) ) );
	mark_de_visible(&(deh[0]));

	/* direntry header of ".." */
	put_deh_offset( &(deh[1]), DOT_DOT_OFFSET );
	/* key of ".." for the root directory */
	/* these two are from the inode, and are are LE */
	deh[1].deh_dir_id = par_dirid;
	deh[1].deh_objectid = par_objid;
	deh[1].deh_state = 0; /* Endian safe if 0 */
	put_deh_location( &(deh[1]), deh_location( &(deh[0])) - ROUND_UP( strlen( ".." ) ) );
	mark_de_visible(&(deh[1]));

	/* copy ".." and "." */
	memcpy (body + deh_location( &(deh[0]) ), ".", 1);
	memcpy (body + deh_location( &(deh[1]) ), "..", 2);
	}