Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   1) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   2)  * fs/sdcardfs/dentry.c
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   3)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   4)  * Copyright (c) 2013 Samsung Electronics Co. Ltd
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   5)  *   Authors: Daeho Jeong, Woojoong Lee, Seunghwan Hyun,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   6)  *               Sunghwan Yun, Sungjong Seo
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   7)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   8)  * This program has been developed as a stackable file system based on
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   9)  * the WrapFS which written by
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  10)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  11)  * Copyright (c) 1998-2011 Erez Zadok
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  12)  * Copyright (c) 2009     Shrikar Archak
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  13)  * Copyright (c) 2003-2011 Stony Brook University
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  14)  * Copyright (c) 2003-2011 The Research Foundation of SUNY
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  15)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  16)  * This file is dual licensed.  It may be redistributed and/or modified
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  17)  * under the terms of the Apache 2.0 License OR version 2 of the GNU
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  18)  * General Public License.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  19)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  20) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  21) #include "sdcardfs.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  22) #include "linux/ctype.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  23) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  24) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  25)  * returns: -ERRNO if error (returned to user)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  26)  *          0: tell VFS to invalidate dentry
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  27)  *          1: dentry is valid
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  28)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  29) static int sdcardfs_d_revalidate(struct dentry *dentry, unsigned int flags)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  30) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  31) 	int err = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  32) 	struct path parent_lower_path, lower_path;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  33) 	struct dentry *parent_dentry = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  34) 	struct dentry *parent_lower_dentry = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  35) 	struct dentry *lower_cur_parent_dentry = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  36) 	struct dentry *lower_dentry = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  37) 	struct inode *inode;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  38) 	struct sdcardfs_inode_data *data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  39) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  40) 	if (flags & LOOKUP_RCU)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  41) 		return -ECHILD;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  42) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  43) 	spin_lock(&dentry->d_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  44) 	if (IS_ROOT(dentry)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  45) 		spin_unlock(&dentry->d_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  46) 		return 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  47) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  48) 	spin_unlock(&dentry->d_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  49) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  50) 	/* check uninitialized obb_dentry and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  51) 	 * whether the base obbpath has been changed or not
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  52) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  53) 	if (is_obbpath_invalid(dentry)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  54) 		return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  55) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  56) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  57) 	parent_dentry = dget_parent(dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  58) 	sdcardfs_get_lower_path(parent_dentry, &parent_lower_path);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  59) 	sdcardfs_get_real_lower(dentry, &lower_path);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  60) 	parent_lower_dentry = parent_lower_path.dentry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  61) 	lower_dentry = lower_path.dentry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  62) 	lower_cur_parent_dentry = dget_parent(lower_dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  63) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  64) 	if ((lower_dentry->d_flags & DCACHE_OP_REVALIDATE)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  65) 		err = lower_dentry->d_op->d_revalidate(lower_dentry, flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  66) 		if (err == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  67) 			goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  68) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  69) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  70) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  71) 	spin_lock(&lower_dentry->d_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  72) 	if (d_unhashed(lower_dentry)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  73) 		spin_unlock(&lower_dentry->d_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  74) 		err = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  75) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  76) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  77) 	spin_unlock(&lower_dentry->d_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  78) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  79) 	if (parent_lower_dentry != lower_cur_parent_dentry) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  80) 		err = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  81) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  82) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  83) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  84) 	if (dentry < lower_dentry) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  85) 		spin_lock(&dentry->d_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  86) 		spin_lock_nested(&lower_dentry->d_lock, DENTRY_D_LOCK_NESTED);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  87) 	} else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  88) 		spin_lock(&lower_dentry->d_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  89) 		spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  90) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  91) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  92) 	if (!qstr_case_eq(&dentry->d_name, &lower_dentry->d_name)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  93) 		err = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  94) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  95) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  96) 	if (dentry < lower_dentry) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  97) 		spin_unlock(&lower_dentry->d_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  98) 		spin_unlock(&dentry->d_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  99) 	} else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) 		spin_unlock(&dentry->d_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) 		spin_unlock(&lower_dentry->d_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) 	if (!err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) 	/* If our top's inode is gone, we may be out of date */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) 	inode = igrab(d_inode(dentry));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) 	if (inode) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) 		data = top_data_get(SDCARDFS_I(inode));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) 		if (!data || data->abandoned) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) 			err = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) 		if (data)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) 			data_put(data);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) 		iput(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) 	dput(parent_dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) 	dput(lower_cur_parent_dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) 	sdcardfs_put_lower_path(parent_dentry, &parent_lower_path);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) 	sdcardfs_put_real_lower(dentry, &lower_path);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) 	return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) /* 1 = delete, 0 = cache */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) static int sdcardfs_d_delete(const struct dentry *d)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) 	return SDCARDFS_SB(d->d_sb)->options.nocache ? 1 : 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) static void sdcardfs_d_release(struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) 	if (!dentry || !dentry->d_fsdata)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) 		return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) 	/* release and reset the lower paths */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) 	if (has_graft_path(dentry))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) 		sdcardfs_put_reset_orig_path(dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) 	sdcardfs_put_reset_lower_path(dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) 	free_dentry_private_data(dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) static int sdcardfs_hash_ci(const struct dentry *dentry,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) 				struct qstr *qstr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) 	 * This function is copy of vfat_hashi.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) 	 * FIXME Should we support national language?
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) 	 *       Refer to vfat_hashi()
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) 	 * struct nls_table *t = MSDOS_SB(dentry->d_sb)->nls_io;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) 	const unsigned char *name;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) 	unsigned int len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) 	unsigned long hash;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) 	name = qstr->name;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) 	len = qstr->len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) 	hash = init_name_hash(dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) 	while (len--)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) 		hash = partial_name_hash(tolower(*name++), hash);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) 	qstr->hash = end_name_hash(hash);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168)  * Case insensitive compare of two vfat names.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) static int sdcardfs_cmp_ci(const struct dentry *dentry,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) 		unsigned int len, const char *str, const struct qstr *name)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) 	/* FIXME Should we support national language? */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) 	if (name->len == len) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) 		if (str_n_case_eq(name->name, str, len))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) 			return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) 	return 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) static void sdcardfs_canonical_path(const struct path *path,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) 				struct path *actual_path)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) 	sdcardfs_get_real_lower(path->dentry, actual_path);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) const struct dentry_operations sdcardfs_ci_dops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) 	.d_revalidate	= sdcardfs_d_revalidate,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) 	.d_delete	= sdcardfs_d_delete,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) 	.d_release	= sdcardfs_d_release,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) 	.d_hash	= sdcardfs_hash_ci,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) 	.d_compare	= sdcardfs_cmp_ci,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) 	.d_canonical_path = sdcardfs_canonical_path,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196)