get rid of 'parent' argument of ->d_compare()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Documentation/filesystems/Locking

@@ -12,7 +12,7 @@ prototypes:
 	int (*d_revalidate)(struct dentry *, unsigned int);
 	int (*d_weak_revalidate)(struct dentry *, unsigned int);
 	int (*d_hash)(const struct dentry *, struct qstr *);
-	int (*d_compare)(const struct dentry *, const struct dentry *,
+	int (*d_compare)(const struct dentry *,
 			unsigned int, const char *, const struct qstr *);
 	int (*d_delete)(struct dentry *);
 	int (*d_init)(struct dentry *);

Documentation/filesystems/porting

@@ -585,3 +585,10 @@ in your dentry operations instead.
 	in the instances.  Rationale: !@#!@# security_d_instantiate() needs to be
 	called before we attach dentry to inode and !@#!@##!@$!$#!@#$!@$!@$ smack
 	->d_instantiate() uses not just ->getxattr() but ->setxattr() as well.
+--
+[mandatory]
+	->d_compare() doesn't get parent as a separate argument anymore.  If you
+	used it for finding the struct super_block involved, dentry->d_sb will
+	work just as well; if it's something more complicated, use dentry->d_parent.
+	Just be careful not to assume that fetching it more than once will yield
+	the same value - in RCU mode it could change under you.

Documentation/filesystems/vfs.txt

@@ -931,7 +931,7 @@ struct dentry_operations {
 	int (*d_revalidate)(struct dentry *, unsigned int);
 	int (*d_weak_revalidate)(struct dentry *, unsigned int);
 	int (*d_hash)(const struct dentry *, struct qstr *);
-	int (*d_compare)(const struct dentry *, const struct dentry *,
+	int (*d_compare)(const struct dentry *,
 			unsigned int, const char *, const struct qstr *);
 	int (*d_delete)(const struct dentry *);
 	int (*d_init)(struct dentry *);

drivers/staging/lustre/lustre/llite/dcache.c

@@ -78,7 +78,7 @@ static void ll_release(struct dentry *de)
  * INVALID) so d_lookup() matches it, but we have no lock on it (so
  * lock_match() fails) and we spin around real_lookup().
  */
-static int ll_dcompare(const struct dentry *parent, const struct dentry *dentry,
+static int ll_dcompare(const struct dentry *dentry,
 		       unsigned int len, const char *str,
 		       const struct qstr *name)
 {

fs/adfs/dir.c

@@ -227,7 +227,7 @@ adfs_hash(const struct dentry *parent, struct qstr *qstr)
  * requirements of the underlying filesystem.
  */
 static int
-adfs_compare(const struct dentry *parent, const struct dentry *dentry,
+adfs_compare(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
 	int i;

fs/affs/namei.c

@@ -14,11 +14,11 @@ typedef int (*toupper_t)(int);
 
 static int	 affs_toupper(int ch);
 static int	 affs_hash_dentry(const struct dentry *, struct qstr *);
-static int       affs_compare_dentry(const struct dentry *parent, const struct dentry *dentry,
+static int       affs_compare_dentry(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name);
 static int	 affs_intl_toupper(int ch);
 static int	 affs_intl_hash_dentry(const struct dentry *, struct qstr *);
-static int       affs_intl_compare_dentry(const struct dentry *parent, const struct dentry *dentry,
+static int       affs_intl_compare_dentry(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name);
 
 const struct dentry_operations affs_dentry_operations = {
@@ -131,7 +131,7 @@ static inline int __affs_compare_dentry(unsigned int len,
 }
 
 static int
-affs_compare_dentry(const struct dentry *parent, const struct dentry *dentry,
+affs_compare_dentry(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
 
@@ -140,7 +140,7 @@ affs_compare_dentry(const struct dentry *parent, const struct dentry *dentry,
 }
 
 static int
-affs_intl_compare_dentry(const struct dentry *parent, const struct dentry *dentry,
+affs_intl_compare_dentry(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
 	return __affs_compare_dentry(len, str, name, affs_intl_toupper,

fs/cifs/dir.c

@@ -903,7 +903,7 @@ static int cifs_ci_hash(const struct dentry *dentry, struct qstr *q)
 	return 0;
 }
 
-static int cifs_ci_compare(const struct dentry *parent, const struct dentry *dentry,
+static int cifs_ci_compare(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
 	struct nls_table *codepage = CIFS_SB(dentry->d_sb)->local_nls;

fs/dcache.c

@@ -2047,7 +2047,7 @@ static inline bool d_same_name(const struct dentry *dentry,
 			return false;
 		return dentry_cmp(dentry, name->name, name->len) == 0;
 	}
-	return parent->d_op->d_compare(parent, dentry,
+	return parent->d_op->d_compare(dentry,
 				       dentry->d_name.len, dentry->d_name.name,
 				       name) == 0;
 }
@@ -2150,7 +2150,7 @@ struct dentry *__d_lookup_rcu(const struct dentry *parent,
 				cpu_relax();
 				goto seqretry;
 			}
-			if (parent->d_op->d_compare(parent, dentry,
+			if (parent->d_op->d_compare(dentry,
 						    tlen, tname, name) != 0)
 				continue;
 		} else {

fs/efivarfs/super.c

@@ -45,8 +45,7 @@ static struct super_block *efivarfs_sb;
  * So we need to perform a case-sensitive match on part 1 and a
  * case-insensitive match on part 2.
  */
-static int efivarfs_d_compare(const struct dentry *parent,
-			      const struct dentry *dentry,
+static int efivarfs_d_compare(const struct dentry *dentry,
 			      unsigned int len, const char *str,
 			      const struct qstr *name)
 {

fs/fat/namei_msdos.c

@@ -162,7 +162,7 @@ static int msdos_hash(const struct dentry *dentry, struct qstr *qstr)
  * Compare two msdos names. If either of the names are invalid,
  * we fall back to doing the standard name comparison.
  */
-static int msdos_cmp(const struct dentry *parent, const struct dentry *dentry,
+static int msdos_cmp(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
 	struct fat_mount_options *options = &MSDOS_SB(dentry->d_sb)->options;

fs/fat/namei_vfat.c

@@ -138,7 +138,7 @@ static int vfat_hashi(const struct dentry *dentry, struct qstr *qstr)
 /*
  * Case insensitive compare of two vfat names.
  */
-static int vfat_cmpi(const struct dentry *parent, const struct dentry *dentry,
+static int vfat_cmpi(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
 	struct nls_table *t = MSDOS_SB(dentry->d_sb)->nls_io;
@@ -157,7 +157,7 @@ static int vfat_cmpi(const struct dentry *parent, const struct dentry *dentry,
 /*
  * Case sensitive compare of two vfat names.
  */
-static int vfat_cmp(const struct dentry *parent, const struct dentry *dentry,
+static int vfat_cmp(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
 	unsigned int alen, blen;

fs/hfs/hfs_fs.h

@@ -233,7 +233,7 @@ extern const struct dentry_operations hfs_dentry_operations;
 extern int hfs_hash_dentry(const struct dentry *, struct qstr *);
 extern int hfs_strcmp(const unsigned char *, unsigned int,
 		      const unsigned char *, unsigned int);
-extern int hfs_compare_dentry(const struct dentry *parent, const struct dentry *dentry,
+extern int hfs_compare_dentry(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name);
 
 /* trans.c */

fs/hfs/string.c

@@ -92,7 +92,7 @@ int hfs_strcmp(const unsigned char *s1, unsigned int len1,
  * Test for equality of two strings in the HFS filename character ordering.
  * return 1 on failure and 0 on success
  */
-int hfs_compare_dentry(const struct dentry *parent, const struct dentry *dentry,
+int hfs_compare_dentry(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
 	const unsigned char *n1, *n2;

fs/hfsplus/hfsplus_fs.h

@@ -520,8 +520,7 @@ int hfsplus_uni2asc(struct super_block *sb, const struct hfsplus_unistr *ustr,
 int hfsplus_asc2uni(struct super_block *sb, struct hfsplus_unistr *ustr,
 		    int max_unistr_len, const char *astr, int len);
 int hfsplus_hash_dentry(const struct dentry *dentry, struct qstr *str);
-int hfsplus_compare_dentry(const struct dentry *parent,
-			   const struct dentry *dentry, unsigned int len,
+int hfsplus_compare_dentry(const struct dentry *dentry, unsigned int len,
 			   const char *str, const struct qstr *name);
 
 /* wrapper.c */

fs/hfsplus/unicode.c

@@ -385,7 +385,7 @@ int hfsplus_hash_dentry(const struct dentry *dentry, struct qstr *str)
  * Composed unicode characters are decomposed and case-folding is performed
  * if the appropriate bits are (un)set on the superblock.
  */
-int hfsplus_compare_dentry(const struct dentry *parent, const struct dentry *dentry,
+int hfsplus_compare_dentry(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
 	struct super_block *sb = dentry->d_sb;

fs/hpfs/dentry.c

@@ -34,7 +34,7 @@ static int hpfs_hash_dentry(const struct dentry *dentry, struct qstr *qstr)
 	return 0;
 }
 
-static int hpfs_compare_dentry(const struct dentry *parent, const struct dentry *dentry,
+static int hpfs_compare_dentry(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
 	unsigned al = len;

fs/isofs/inode.c

@@ -29,18 +29,15 @@
 #define BEQUIET
 
 static int isofs_hashi(const struct dentry *parent, struct qstr *qstr);
-static int isofs_dentry_cmpi(const struct dentry *parent,
-		const struct dentry *dentry,
+static int isofs_dentry_cmpi(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name);
 
 #ifdef CONFIG_JOLIET
 static int isofs_hashi_ms(const struct dentry *parent, struct qstr *qstr);
 static int isofs_hash_ms(const struct dentry *parent, struct qstr *qstr);
-static int isofs_dentry_cmpi_ms(const struct dentry *parent,
-		const struct dentry *dentry,
+static int isofs_dentry_cmpi_ms(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name);
-static int isofs_dentry_cmp_ms(const struct dentry *parent,
-		const struct dentry *dentry,
+static int isofs_dentry_cmp_ms(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name);
 #endif
 
@@ -235,7 +232,7 @@ isofs_hashi(const struct dentry *dentry, struct qstr *qstr)
 }
 
 static int
-isofs_dentry_cmpi(const struct dentry *parent, const struct dentry *dentry,
+isofs_dentry_cmpi(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
 	return isofs_dentry_cmp_common(len, str, name, 0, 1);
@@ -276,14 +273,14 @@ isofs_hashi_ms(const struct dentry *dentry, struct qstr *qstr)
 }
 
 static int
-isofs_dentry_cmp_ms(const struct dentry *parent, const struct dentry *dentry,
+isofs_dentry_cmp_ms(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
 	return isofs_dentry_cmp_common(len, str, name, 1, 0);
 }
 
 static int
-isofs_dentry_cmpi_ms(const struct dentry *parent, const struct dentry *dentry,
+isofs_dentry_cmpi_ms(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
 	return isofs_dentry_cmp_common(len, str, name, 1, 1);

fs/isofs/namei.c

@@ -22,7 +22,7 @@ isofs_cmp(struct dentry *dentry, const char *compare, int dlen)
 	qstr.len = dlen;
 	if (likely(!dentry->d_op))
 		return dentry->d_name.len != dlen || memcmp(dentry->d_name.name, compare, dlen);
-	return dentry->d_op->d_compare(NULL, NULL, dentry->d_name.len, dentry->d_name.name, &qstr);
+	return dentry->d_op->d_compare(NULL, dentry->d_name.len, dentry->d_name.name, &qstr);
 }
 
 /*

fs/jfs/namei.c

@@ -1572,7 +1572,7 @@ static int jfs_ci_hash(const struct dentry *dir, struct qstr *this)
 	return 0;
 }
 
-static int jfs_ci_compare(const struct dentry *parent, const struct dentry *dentry,
+static int jfs_ci_compare(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
 	int i, result = 1;

fs/ncpfs/dir.c

@@ -74,7 +74,7 @@ const struct inode_operations ncp_dir_inode_operations =
  */
 static int ncp_lookup_validate(struct dentry *, unsigned int);
 static int ncp_hash_dentry(const struct dentry *, struct qstr *);
-static int ncp_compare_dentry(const struct dentry *, const struct dentry *,
+static int ncp_compare_dentry(const struct dentry *,
 		unsigned int, const char *, const struct qstr *);
 static int ncp_delete_dentry(const struct dentry *);
 static void ncp_d_prune(struct dentry *dentry);
@@ -154,7 +154,7 @@ ncp_hash_dentry(const struct dentry *dentry, struct qstr *this)
  * the callers will handle races.
  */
 static int
-ncp_compare_dentry(const struct dentry *parent, const struct dentry *dentry,
+ncp_compare_dentry(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
 	struct inode *pinode;
@@ -162,7 +162,7 @@ ncp_compare_dentry(const struct dentry *parent, const struct dentry *dentry,
 	if (len != name->len)
 		return 1;
 
-	pinode = d_inode_rcu(parent);
+	pinode = d_inode_rcu(dentry->d_parent);
 	if (!pinode)
 		return 1;
 

fs/proc/proc_sysctl.c

@@ -834,7 +834,7 @@ static int sysctl_is_seen(struct ctl_table_header *p)
 	return res;
 }
 
-static int proc_sys_compare(const struct dentry *parent, const struct dentry *dentry,
+static int proc_sys_compare(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
 	struct ctl_table_header *head;

include/linux/dcache.h

@@ -130,7 +130,7 @@ struct dentry_operations {
 	int (*d_revalidate)(struct dentry *, unsigned int);
 	int (*d_weak_revalidate)(struct dentry *, unsigned int);
 	int (*d_hash)(const struct dentry *, struct qstr *);
-	int (*d_compare)(const struct dentry *, const struct dentry *,
+	int (*d_compare)(const struct dentry *,
 			unsigned int, const char *, const struct qstr *);
 	int (*d_delete)(const struct dentry *);
 	int (*d_init)(struct dentry *);