[GitHub/mt8127/android_kernel_alcatel_ttab.git] / fs / reiserfs / dir.c

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

#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);

const struct file_operations reiserfs_dir_operations = {
	.read = generic_read_dir,
	.readdir = reiserfs_readdir,
	.fsync = reiserfs_dir_fsync,
	.ioctl = reiserfs_ioctl,
#ifdef CONFIG_COMPAT
	.compat_ioctl = reiserfs_compat_ioctl,
#endif
};

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 = kmalloc(d_reclen,
							    GFP_NOFS);
					if (!local_buf) {
						pathrelse(&path_to_entry);
						ret = -ENOMEM;
						goto out;
					}
					if (item_moved(&tmp_ih, &path_to_entry)) {
						kfree(local_buf);
						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) {
						kfree(local_buf);
					}
					goto end;
				}
				if (local_buf != small_buf) {
					kfree(local_buf);
				}
				// 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, __le32 dirid, __le32 objid,
			    __le32 par_dirid, __le32 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, __le32 dirid, __le32 objid,
			 __le32 par_dirid, __le32 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);
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
	3	*/
	4
1da177e4 LT	5	#include <linux/string.h>
	6	#include <linux/errno.h>
	7	#include <linux/fs.h>
	8	#include <linux/reiserfs_fs.h>
	9	#include <linux/stat.h>
	10	#include <linux/smp_lock.h>
	11	#include <linux/buffer_head.h>
	12	#include <asm/uaccess.h>
	13
bd4c625c	14	extern struct reiserfs_key MIN_KEY;
1da177e4	15
bd4c625c LT	16	static int reiserfs_readdir(struct file , void , filldir_t);
	17	static int reiserfs_dir_fsync(struct file filp, struct dentry dentry,
	18	int datasync);
1da177e4	19
4b6f5d20	20	const struct file_operations reiserfs_dir_operations = {
bd4c625c LT	21	.read = generic_read_dir,
	22	.readdir = reiserfs_readdir,
	23	.fsync = reiserfs_dir_fsync,
	24	.ioctl = reiserfs_ioctl,
52b499c4 DH	25	#ifdef CONFIG_COMPAT
	26	.compat_ioctl = reiserfs_compat_ioctl,
	27	#endif
1da177e4 LT	28	};
1da177e4 LT	29
bd4c625c LT	30	static int reiserfs_dir_fsync(struct file filp, struct dentry dentry,
	31	int datasync)
	32	{
	33	struct inode *inode = dentry->d_inode;
	34	int err;
	35	reiserfs_write_lock(inode->i_sb);
	36	err = reiserfs_commit_for_inode(inode);
	37	reiserfs_write_unlock(inode->i_sb);
	38	if (err < 0)
	39	return err;
	40	return 0;
1da177e4 LT	41	}
1da177e4 LT	42
1da177e4 LT	43	#define store_ih(where,what) copy_item_head (where, what)
	44
	45	//
bd4c625c	46	static int reiserfs_readdir(struct file filp, void dirent, filldir_t filldir)
1da177e4	47	{
bd4c625c LT	48	struct inode *inode = filp->f_dentry->d_inode;
	49	struct cpu_key pos_key; /* key of current position in the directory (key of directory entry) */
	50	INITIALIZE_PATH(path_to_entry);
	51	struct buffer_head *bh;
	52	int item_num, entry_num;
	53	const struct reiserfs_key *rkey;
	54	struct item_head *ih, tmp_ih;
	55	int search_res;
	56	char *local_buf;
	57	loff_t next_pos;
	58	char small_buf[32]; /* avoid kmalloc if we can */
	59	struct reiserfs_dir_entry de;
	60	int ret = 0;
	61
	62	reiserfs_write_lock(inode->i_sb);
	63
	64	reiserfs_check_lock_depth(inode->i_sb, "readdir");
	65
	66	/* form key for search the next directory entry using f_pos field of
	67	file structure */
	68	make_cpu_key(&pos_key, inode,
	69	(filp->f_pos) ? (filp->f_pos) : DOT_OFFSET, TYPE_DIRENTRY,
	70	3);
	71	next_pos = cpu_key_k_offset(&pos_key);
	72
	73	/* reiserfs_warning (inode->i_sb, "reiserfs_readdir 1: f_pos = %Ld", filp->f_pos); */
	74
	75	path_to_entry.reada = PATH_READA;
	76	while (1) {
	77	research:
	78	/* search the directory item, containing entry with specified key */
	79	search_res =
	80	search_by_entry_key(inode->i_sb, &pos_key, &path_to_entry,
	81	&de);
	82	if (search_res == IO_ERROR) {
	83	// FIXME: we could just skip part of directory which could
	84	// not be read
	85	ret = -EIO;
1da177e4	86	goto out;
1da177e4	87	}
bd4c625c LT	88	entry_num = de.de_entry_num;
	89	bh = de.de_bh;
	90	item_num = de.de_item_num;
	91	ih = de.de_ih;
	92	store_ih(&tmp_ih, ih);
	93
	94	/* we must have found item, that is item of this directory, */
	95	RFALSE(COMP_SHORT_KEYS(&(ih->ih_key), &pos_key),
	96	"vs-9000: found item %h does not match to dir we readdir %K",
	97	ih, &pos_key);
	98	RFALSE(item_num > B_NR_ITEMS(bh) - 1,
	99	"vs-9005 item_num == %d, item amount == %d",
	100	item_num, B_NR_ITEMS(bh));
	101
	102	/* and entry must be not more than number of entries in the item */
	103	RFALSE(I_ENTRY_COUNT(ih) < entry_num,
	104	"vs-9010: entry number is too big %d (%d)",
	105	entry_num, I_ENTRY_COUNT(ih));
	106
	107	if (search_res == POSITION_FOUND
	108	\|\| entry_num < I_ENTRY_COUNT(ih)) {
	109	/* go through all entries in the directory item beginning from the entry, that has been found */
	110	struct reiserfs_de_head *deh =
	111	B_I_DEH(bh, ih) + entry_num;
	112
	113	for (; entry_num < I_ENTRY_COUNT(ih);
	114	entry_num++, deh++) {
	115	int d_reclen;
	116	char *d_name;
	117	off_t d_off;
	118	ino_t d_ino;
	119
	120	if (!de_visible(deh))
	121	/* it is hidden entry */
	122	continue;
	123	d_reclen = entry_length(bh, ih, entry_num);
	124	d_name = B_I_DEH_ENTRY_FILE_NAME(bh, ih, deh);
	125	if (!d_name[d_reclen - 1])
	126	d_reclen = strlen(d_name);
	127
	128	if (d_reclen >
	129	REISERFS_MAX_NAME(inode->i_sb->
	130	s_blocksize)) {
	131	/* too big to send back to VFS */
	132	continue;
	133	}
	134
	135	/* Ignore the .reiserfs_priv entry */
	136	if (reiserfs_xattrs(inode->i_sb) &&
	137	!old_format_only(inode->i_sb) &&
	138	filp->f_dentry == inode->i_sb->s_root &&
	139	REISERFS_SB(inode->i_sb)->priv_root &&
	140	REISERFS_SB(inode->i_sb)->priv_root->d_inode
	141	&& deh_objectid(deh) ==
	142	le32_to_cpu(INODE_PKEY
	143	(REISERFS_SB(inode->i_sb)->
	144	priv_root->d_inode)->
	145	k_objectid)) {
	146	continue;
	147	}
	148
	149	d_off = deh_offset(deh);
	150	filp->f_pos = d_off;
	151	d_ino = deh_objectid(deh);
152	if (d_reclen <= 32) {
153	local_buf = small_buf;
154	} else {
d739b42b PE	155	local_buf = kmalloc(d_reclen,
d739b42b PE	156	GFP_NOFS);
bd4c625c LT	157	if (!local_buf) {
	158	pathrelse(&path_to_entry);
	159	ret = -ENOMEM;
	160	goto out;
	161	}
	162	if (item_moved(&tmp_ih, &path_to_entry)) {
d739b42b	163	kfree(local_buf);
bd4c625c LT	164	goto research;
	165	}
	166	}
	167	// Note, that we copy name to user space via temporary
	168	// buffer (local_buf) because filldir will block if
	169	// user space buffer is swapped out. At that time
	170	// entry can move to somewhere else
	171	memcpy(local_buf, d_name, d_reclen);
	172	if (filldir
	173	(dirent, local_buf, d_reclen, d_off, d_ino,
	174	DT_UNKNOWN) < 0) {
	175	if (local_buf != small_buf) {
d739b42b	176	kfree(local_buf);
bd4c625c LT	177	}
	178	goto end;
	179	}
	180	if (local_buf != small_buf) {
d739b42b	181	kfree(local_buf);
bd4c625c LT	182	}
	183	// next entry should be looked for with such offset
	184	next_pos = deh_offset(deh) + 1;
	185
	186	if (item_moved(&tmp_ih, &path_to_entry)) {
	187	goto research;
	188	}
	189	} /* for */
1da177e4 LT	190	}
1da177e4 LT	191
bd4c625c LT	192	if (item_num != B_NR_ITEMS(bh) - 1)
	193	// end of directory has been reached
	194	goto end;
	195
	196	/* item we went through is last item of node. Using right
	197	delimiting key check is it directory end */
	198	rkey = get_rkey(&path_to_entry, inode->i_sb);
	199	if (!comp_le_keys(rkey, &MIN_KEY)) {
	200	/* set pos_key to key, that is the smallest and greater
	201	that key of the last entry in the item */
	202	set_cpu_key_k_offset(&pos_key, next_pos);
	203	continue;
	204	}
1da177e4	205
bd4c625c LT	206	if (COMP_SHORT_KEYS(rkey, &pos_key)) {
	207	// end of directory has been reached
	208	goto end;
1da177e4	209	}
bd4c625c LT	210
	211	/* directory continues in the right neighboring block */
	212	set_cpu_key_k_offset(&pos_key,
	213	le_key_k_offset(KEY_FORMAT_3_5, rkey));
	214
	215	} /* while */
	216
	217	end:
	218	filp->f_pos = next_pos;
	219	pathrelse(&path_to_entry);
	220	reiserfs_check_path(&path_to_entry);
	221	out:
	222	reiserfs_write_unlock(inode->i_sb);
	223	return ret;
1da177e4 LT	224	}
	225
	226	/* compose directory item containing "." and ".." entries (entries are
	227	not aligned to 4 byte boundary) */
	228	/* the last four params are LE */
bd4c625c LT	229	void make_empty_dir_item_v1(char *body, __le32 dirid, __le32 objid,
bd4c625c LT	230	__le32 par_dirid, __le32 par_objid)
1da177e4	231	{
bd4c625c LT	232	struct reiserfs_de_head *deh;
	233
	234	memset(body, 0, EMPTY_DIR_SIZE_V1);
	235	deh = (struct reiserfs_de_head *)body;
	236
	237	/* direntry header of "." */
	238	put_deh_offset(&(deh[0]), DOT_OFFSET);
	239	/* these two are from make_le_item_head, and are are LE */
	240	deh[0].deh_dir_id = dirid;
	241	deh[0].deh_objectid = objid;
	242	deh[0].deh_state = 0; /* Endian safe if 0 */
	243	put_deh_location(&(deh[0]), EMPTY_DIR_SIZE_V1 - strlen("."));
	244	mark_de_visible(&(deh[0]));
	245
	246	/* direntry header of ".." */
	247	put_deh_offset(&(deh[1]), DOT_DOT_OFFSET);
	248	/* key of ".." for the root directory */
	249	/* these two are from the inode, and are are LE */
	250	deh[1].deh_dir_id = par_dirid;
	251	deh[1].deh_objectid = par_objid;
	252	deh[1].deh_state = 0; /* Endian safe if 0 */
	253	put_deh_location(&(deh[1]), deh_location(&(deh[0])) - strlen(".."));
	254	mark_de_visible(&(deh[1]));
	255
	256	/* copy ".." and "." */
	257	memcpy(body + deh_location(&(deh[0])), ".", 1);
	258	memcpy(body + deh_location(&(deh[1])), "..", 2);
1da177e4 LT	259	}
	260
	261	/* compose directory item containing "." and ".." entries */
bd4c625c LT	262	void make_empty_dir_item(char *body, __le32 dirid, __le32 objid,
bd4c625c LT	263	__le32 par_dirid, __le32 par_objid)
1da177e4	264	{
bd4c625c LT	265	struct reiserfs_de_head *deh;
	266
	267	memset(body, 0, EMPTY_DIR_SIZE);
	268	deh = (struct reiserfs_de_head *)body;
	269
	270	/* direntry header of "." */
	271	put_deh_offset(&(deh[0]), DOT_OFFSET);
	272	/* these two are from make_le_item_head, and are are LE */
	273	deh[0].deh_dir_id = dirid;
	274	deh[0].deh_objectid = objid;
	275	deh[0].deh_state = 0; /* Endian safe if 0 */
	276	put_deh_location(&(deh[0]), EMPTY_DIR_SIZE - ROUND_UP(strlen(".")));
	277	mark_de_visible(&(deh[0]));
	278
	279	/* direntry header of ".." */
	280	put_deh_offset(&(deh[1]), DOT_DOT_OFFSET);
	281	/* key of ".." for the root directory */
	282	/* these two are from the inode, and are are LE */
	283	deh[1].deh_dir_id = par_dirid;
	284	deh[1].deh_objectid = par_objid;
	285	deh[1].deh_state = 0; /* Endian safe if 0 */
	286	put_deh_location(&(deh[1]),
	287	deh_location(&(deh[0])) - ROUND_UP(strlen("..")));
	288	mark_de_visible(&(deh[1]));
	289
	290	/* copy ".." and "." */
	291	memcpy(body + deh_location(&(deh[0])), ".", 1);
	292	memcpy(body + deh_location(&(deh[1])), "..", 2);
1da177e4	293	}