Merge branch 'merge.nfs-fs_parse.1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull vfs file system parameter updates from Al Viro:
 "Saner fs_parser.c guts and data structures. The system-wide registry
  of syntax types (string/enum/int32/oct32/.../etc.) is gone and so is
  the horror switch() in fs_parse() that would have to grow another case
  every time something got added to that system-wide registry.

  New syntax types can be added by filesystems easily now, and their
  namespace is that of functions - not of system-wide enum members. IOW,
  they can be shared or kept private and if some turn out to be widely
  useful, we can make them common library helpers, etc., without having
  to do anything whatsoever to fs_parse() itself.

  And we already get that kind of requests - the thing that finally
  pushed me into doing that was "oh, and let's add one for timeouts -
  things like 15s or 2h". If some filesystem really wants that, let them
  do it. Without somebody having to play gatekeeper for the variants
  blessed by direct support in fs_parse(), TYVM.

  Quite a bit of boilerplate is gone. And IMO the data structures make a
  lot more sense now. -200LoC, while we are at it"

* 'merge.nfs-fs_parse.1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (25 commits)
  tmpfs: switch to use of invalfc()
  cgroup1: switch to use of errorfc() et.al.
  procfs: switch to use of invalfc()
  hugetlbfs: switch to use of invalfc()
  cramfs: switch to use of errofc() et.al.
  gfs2: switch to use of errorfc() et.al.
  fuse: switch to use errorfc() et.al.
  ceph: use errorfc() and friends instead of spelling the prefix out
  prefix-handling analogues of errorf() and friends
  turn fs_param_is_... into functions
  fs_parse: handle optional arguments sanely
  fs_parse: fold fs_parameter_desc/fs_parameter_spec
  fs_parser: remove fs_parameter_description name field
  add prefix to fs_context->log
  ceph_parse_param(), ceph_parse_mon_ips(): switch to passing fc_log
  new primitive: __fs_parse()
  switch rbd and libceph to p_log-based primitives
  struct p_log, variants of warnf() et.al. taking that one instead
  teach logfc() to handle prefices, give it saner calling conventions
  get rid of cg_invalf()
  ...

1 files changed, 188 insertions, 259 deletions

diff --git a/fs/fs_parser.c b/fs/fs_parser.c
index d1930adce68d..7e6fb43f9541 100644
--- a/fs/fs_parser.c
+++ b/fs/fs_parser.c
@@ -20,42 +20,66 @@ static const struct constant_table bool_names[] = {
 	{ "no",		false },
 	{ "true",	true },
 	{ "yes",	true },
+	{ },
 };
 
+static const struct constant_table *
+__lookup_constant(const struct constant_table *tbl, const char *name)
+{
+	for ( ; tbl->name; tbl++)
+		if (strcmp(name, tbl->name) == 0)
+			return tbl;
+	return NULL;
+}
+
 /**
  * lookup_constant - Look up a constant by name in an ordered table
  * @tbl: The table of constants to search.
- * @tbl_size: The size of the table.
  * @name: The name to look up.
  * @not_found: The value to return if the name is not found.
  */
-int __lookup_constant(const struct constant_table *tbl, size_t tbl_size,
-		      const char *name, int not_found)
+int lookup_constant(const struct constant_table *tbl, const char *name, int not_found)
 {
-	unsigned int i;
+	const struct constant_table *p = __lookup_constant(tbl, name);
 
-	for (i = 0; i < tbl_size; i++)
-		if (strcmp(name, tbl[i].name) == 0)
-			return tbl[i].value;
+	return p ? p->value : not_found;
+}
+EXPORT_SYMBOL(lookup_constant);
 
-	return not_found;
+static inline bool is_flag(const struct fs_parameter_spec *p)
+{
+	return p->type == NULL;
 }
-EXPORT_SYMBOL(__lookup_constant);
 
 static const struct fs_parameter_spec *fs_lookup_key(
-	const struct fs_parameter_description *desc,
-	const char *name)
+	const struct fs_parameter_spec *desc,
+	struct fs_parameter *param, bool *negated)
 {
-	const struct fs_parameter_spec *p;
-
-	if (!desc->specs)
-		return NULL;
-
-	for (p = desc->specs; p->name; p++)
-		if (strcmp(p->name, name) == 0)
+	const struct fs_parameter_spec *p, *other = NULL;
+	const char *name = param->key;
+	bool want_flag = param->type == fs_value_is_flag;
+
+	*negated = false;
+	for (p = desc; p->name; p++) {
+		if (strcmp(p->name, name) != 0)
+			continue;
+		if (likely(is_flag(p) == want_flag))
 			return p;
-
-	return NULL;
+		other = p;
+	}
+	if (want_flag) {
+		if (name[0] == 'n' && name[1] == 'o' && name[2]) {
+			for (p = desc; p->name; p++) {
+				if (strcmp(p->name, name + 2) != 0)
+					continue;
+				if (!(p->flags & fs_param_neg_with_no))
+					continue;
+				*negated = true;
+				return p;
+			}
+		}
+	}
+	return other;
 }
 
 /*
@@ -76,172 +100,38 @@ static const struct fs_parameter_spec *fs_lookup_key(
  * unknown parameters are okay and -EINVAL if there was a conversion issue or
  * the parameter wasn't recognised and unknowns aren't okay.
  */
-int fs_parse(struct fs_context *fc,
-	     const struct fs_parameter_description *desc,
+int __fs_parse(struct p_log *log,
+	     const struct fs_parameter_spec *desc,
 	     struct fs_parameter *param,
 	     struct fs_parse_result *result)
 {
 	const struct fs_parameter_spec *p;
-	const struct fs_parameter_enum *e;
-	int ret = -ENOPARAM, b;
 
-	result->has_value = !!param->string;
-	result->negated = false;
 	result->uint_64 = 0;
 
-	p = fs_lookup_key(desc, param->key);
-	if (!p) {
-		/* If we didn't find something that looks like "noxxx", see if
-		 * "xxx" takes the "no"-form negative - but only if there
-		 * wasn't an value.
-		 */
-		if (result->has_value)
-			goto unknown_parameter;
-		if (param->key[0] != 'n' || param->key[1] != 'o' || !param->key[2])
-			goto unknown_parameter;
-
-		p = fs_lookup_key(desc, param->key + 2);
-		if (!p)
-			goto unknown_parameter;
-		if (!(p->flags & fs_param_neg_with_no))
-			goto unknown_parameter;
-		result->boolean = false;
-		result->negated = true;
-	}
+	p = fs_lookup_key(desc, param, &result->negated);
+	if (!p)
+		return -ENOPARAM;
 
 	if (p->flags & fs_param_deprecated)
-		warnf(fc, "%s: Deprecated parameter '%s'",
-		      desc->name, param->key);
-
-	if (result->negated)
-		goto okay;
-
-	/* Certain parameter types only take a string and convert it. */
-	switch (p->type) {
-	case __fs_param_wasnt_defined:
-		return -EINVAL;
-	case fs_param_is_u32:
-	case fs_param_is_u32_octal:
-	case fs_param_is_u32_hex:
-	case fs_param_is_s32:
-	case fs_param_is_u64:
-	case fs_param_is_enum:
-	case fs_param_is_string:
-		if (param->type != fs_value_is_string)
-			goto bad_value;
-		if (!result->has_value) {
-			if (p->flags & fs_param_v_optional)
-				goto okay;
-			goto bad_value;
-		}
-		/* Fall through */
-	default:
-		break;
-	}
+		warn_plog(log, "Deprecated parameter '%s'", param->key);
 
 	/* Try to turn the type we were given into the type desired by the
 	 * parameter and give an error if we can't.
 	 */
-	switch (p->type) {
-	case fs_param_is_flag:
-		if (param->type != fs_value_is_flag &&
-		    (param->type != fs_value_is_string || result->has_value))
-			return invalf(fc, "%s: Unexpected value for '%s'",
-				      desc->name, param->key);
-		result->boolean = true;
-		goto okay;
-
-	case fs_param_is_bool:
-		switch (param->type) {
-		case fs_value_is_flag:
-			result->boolean = true;
-			goto okay;
-		case fs_value_is_string:
-			if (param->size == 0) {
-				result->boolean = true;
-				goto okay;
-			}
-			b = lookup_constant(bool_names, param->string, -1);
-			if (b == -1)
-				goto bad_value;
-			result->boolean = b;
-			goto okay;
-		default:
-			goto bad_value;
-		}
-
-	case fs_param_is_u32:
-		ret = kstrtouint(param->string, 0, &result->uint_32);
-		goto maybe_okay;
-	case fs_param_is_u32_octal:
-		ret = kstrtouint(param->string, 8, &result->uint_32);
-		goto maybe_okay;
-	case fs_param_is_u32_hex:
-		ret = kstrtouint(param->string, 16, &result->uint_32);
-		goto maybe_okay;
-	case fs_param_is_s32:
-		ret = kstrtoint(param->string, 0, &result->int_32);
-		goto maybe_okay;
-	case fs_param_is_u64:
-		ret = kstrtoull(param->string, 0, &result->uint_64);
-		goto maybe_okay;
-
-	case fs_param_is_enum:
-		for (e = desc->enums; e->name[0]; e++) {
-			if (e->opt == p->opt &&
-			    strcmp(e->name, param->string) == 0) {
-				result->uint_32 = e->value;
-				goto okay;
-			}
-		}
-		goto bad_value;
-
-	case fs_param_is_string:
-		goto okay;
-	case fs_param_is_blob:
-		if (param->type != fs_value_is_blob)
-			goto bad_value;
-		goto okay;
-
-	case fs_param_is_fd: {
-		switch (param->type) {
-		case fs_value_is_string:
-			if (!result->has_value)
-				goto bad_value;
-
-			ret = kstrtouint(param->string, 0, &result->uint_32);
-			break;
-		case fs_value_is_file:
-			result->uint_32 = param->dirfd;
-			ret = 0;
-		default:
-			goto bad_value;
-		}
-
-		if (result->uint_32 > INT_MAX)
-			goto bad_value;
-		goto maybe_okay;
-	}
-
-	case fs_param_is_blockdev:
-	case fs_param_is_path:
-		goto okay;
-	default:
-		BUG();
+	if (is_flag(p)) {
+		if (param->type != fs_value_is_flag)
+			return inval_plog(log, "Unexpected value for '%s'",
+				      param->key);
+		result->boolean = !result->negated;
+	} else  {
+		int ret = p->type(log, p, param, result);
+		if (ret)
+			return ret;
 	}
-
-maybe_okay:
-	if (ret < 0)
-		goto bad_value;
-okay:
 	return p->opt;
-
-bad_value:
-	return invalf(fc, "%s: Bad value for '%s'", desc->name, param->key);
-unknown_parameter:
-	return -ENOPARAM;
 }
-EXPORT_SYMBOL(fs_parse);
+EXPORT_SYMBOL(__fs_parse);
 
 /**
  * fs_lookup_param - Look up a path referred to by a parameter
@@ -267,9 +157,6 @@ int fs_lookup_param(struct fs_context *fc,
 			return PTR_ERR(f);
 		put_f = true;
 		break;
-	case fs_value_is_filename_empty:
-		flags = LOOKUP_EMPTY;
-		/* Fall through */
 	case fs_value_is_filename:
 		f = param->name;
 		put_f = false;
@@ -302,6 +189,124 @@ out:
 }
 EXPORT_SYMBOL(fs_lookup_param);
 
+int fs_param_bad_value(struct p_log *log, struct fs_parameter *param)
+{
+	return inval_plog(log, "Bad value for '%s'", param->key);
+}
+
+int fs_param_is_bool(struct p_log *log, const struct fs_parameter_spec *p,
+		     struct fs_parameter *param, struct fs_parse_result *result)
+{
+	int b;
+	if (param->type != fs_value_is_string)
+		return fs_param_bad_value(log, param);
+	b = lookup_constant(bool_names, param->string, -1);
+	if (b == -1)
+		return fs_param_bad_value(log, param);
+	result->boolean = b;
+	return 0;
+}
+EXPORT_SYMBOL(fs_param_is_bool);
+
+int fs_param_is_u32(struct p_log *log, const struct fs_parameter_spec *p,
+		    struct fs_parameter *param, struct fs_parse_result *result)
+{
+	int base = (unsigned long)p->data;
+	if (param->type != fs_value_is_string ||
+	    kstrtouint(param->string, base, &result->uint_32) < 0)
+		return fs_param_bad_value(log, param);
+	return 0;
+}
+EXPORT_SYMBOL(fs_param_is_u32);
+
+int fs_param_is_s32(struct p_log *log, const struct fs_parameter_spec *p,
+		    struct fs_parameter *param, struct fs_parse_result *result)
+{
+	if (param->type != fs_value_is_string ||
+	    kstrtoint(param->string, 0, &result->int_32) < 0)
+		return fs_param_bad_value(log, param);
+	return 0;
+}
+EXPORT_SYMBOL(fs_param_is_s32);
+
+int fs_param_is_u64(struct p_log *log, const struct fs_parameter_spec *p,
+		    struct fs_parameter *param, struct fs_parse_result *result)
+{
+	if (param->type != fs_value_is_string ||
+	    kstrtoull(param->string, 0, &result->uint_64) < 0)
+		return fs_param_bad_value(log, param);
+	return 0;
+}
+EXPORT_SYMBOL(fs_param_is_u64);
+
+int fs_param_is_enum(struct p_log *log, const struct fs_parameter_spec *p,
+		     struct fs_parameter *param, struct fs_parse_result *result)
+{
+	const struct constant_table *c;
+	if (param->type != fs_value_is_string)
+		return fs_param_bad_value(log, param);
+	c = __lookup_constant(p->data, param->string);
+	if (!c)
+		return fs_param_bad_value(log, param);
+	result->uint_32 = c->value;
+	return 0;
+}
+EXPORT_SYMBOL(fs_param_is_enum);
+
+int fs_param_is_string(struct p_log *log, const struct fs_parameter_spec *p,
+		       struct fs_parameter *param, struct fs_parse_result *result)
+{
+	if (param->type != fs_value_is_string || !*param->string)
+		return fs_param_bad_value(log, param);
+	return 0;
+}
+EXPORT_SYMBOL(fs_param_is_string);
+
+int fs_param_is_blob(struct p_log *log, const struct fs_parameter_spec *p,
+		     struct fs_parameter *param, struct fs_parse_result *result)
+{
+	if (param->type != fs_value_is_blob)
+		return fs_param_bad_value(log, param);
+	return 0;
+}
+EXPORT_SYMBOL(fs_param_is_blob);
+
+int fs_param_is_fd(struct p_log *log, const struct fs_parameter_spec *p,
+		  struct fs_parameter *param, struct fs_parse_result *result)
+{
+	switch (param->type) {
+	case fs_value_is_string:
+		if (kstrtouint(param->string, 0, &result->uint_32) < 0)
+			break;
+		if (result->uint_32 <= INT_MAX)
+			return 0;
+		break;
+	case fs_value_is_file:
+		result->uint_32 = param->dirfd;
+		if (result->uint_32 <= INT_MAX)
+			return 0;
+		break;
+	default:
+		break;
+	}
+	return fs_param_bad_value(log, param);
+}
+EXPORT_SYMBOL(fs_param_is_fd);
+
+int fs_param_is_blockdev(struct p_log *log, const struct fs_parameter_spec *p,
+		  struct fs_parameter *param, struct fs_parse_result *result)
+{
+	return 0;
+}
+EXPORT_SYMBOL(fs_param_is_blockdev);
+
+int fs_param_is_path(struct p_log *log, const struct fs_parameter_spec *p,
+		     struct fs_parameter *param, struct fs_parse_result *result)
+{
+	return 0;
+}
+EXPORT_SYMBOL(fs_param_is_path);
+
 #ifdef CONFIG_VALIDATE_FS_PARSER
 /**
  * validate_constant_table - Validate a constant table
@@ -357,102 +362,26 @@ bool validate_constant_table(const struct constant_table *tbl, size_t tbl_size,
  * fs_validate_description - Validate a parameter description
  * @desc: The parameter description to validate.
  */
-bool fs_validate_description(const struct fs_parameter_description *desc)
+bool fs_validate_description(const char *name,
+	const struct fs_parameter_spec *desc)
 {
 	const struct fs_parameter_spec *param, *p2;
-	const struct fs_parameter_enum *e;
-	const char *name = desc->name;
-	unsigned int nr_params = 0;
-	bool good = true, enums = false;
+	bool good = true;
 
 	pr_notice("*** VALIDATE %s ***\n", name);
 
-	if (!name[0]) {
-		pr_err("VALIDATE Parser: No name\n");
-		name = "Unknown";
-		good = false;
-	}
-
-	if (desc->specs) {
-		for (param = desc->specs; param->name; param++) {
-			enum fs_parameter_type t = param->type;
-
-			/* Check that the type is in range */
-			if (t == __fs_param_wasnt_defined ||
-			    t >= nr__fs_parameter_type) {
-				pr_err("VALIDATE %s: PARAM[%s] Bad type %u\n",
-				       name, param->name, t);
-				good = false;
-			} else if (t == fs_param_is_enum) {
-				enums = true;
-			}
-
-			/* Check for duplicate parameter names */
-			for (p2 = desc->specs; p2 < param; p2++) {
-				if (strcmp(param->name, p2->name) == 0) {
-					pr_err("VALIDATE %s: PARAM[%s]: Duplicate\n",
-					       name, param->name);
-					good = false;
-				}
-			}
-		}
-
-		nr_params = param - desc->specs;
-	}
-
-	if (desc->enums) {
-		if (!nr_params) {
-			pr_err("VALIDATE %s: Enum table but no parameters\n",
-			       name);
-			good = false;
-			goto no_enums;
-		}
-		if (!enums) {
-			pr_err("VALIDATE %s: Enum table but no enum-type values\n",
-			       name);
-			good = false;
-			goto no_enums;
-		}
-
-		for (e = desc->enums; e->name[0]; e++) {
-			/* Check that all entries in the enum table have at
-			 * least one parameter that uses them.
-			 */
-			for (param = desc->specs; param->name; param++) {
-				if (param->opt == e->opt &&
-				    param->type != fs_param_is_enum) {
-					pr_err("VALIDATE %s: e[%tu] enum val for %s\n",
-					       name, e - desc->enums, param->name);
-					good = false;
-				}
-			}
-		}
-
-		/* Check that all enum-type parameters have at least one enum
-		 * value in the enum table.
-		 */
-		for (param = desc->specs; param->name; param++) {
-			if (param->type != fs_param_is_enum)
-				continue;
-			for (e = desc->enums; e->name[0]; e++)
-				if (e->opt == param->opt)
-					break;
-			if (!e->name[0]) {
-				pr_err("VALIDATE %s: PARAM[%s] enum with no values\n",
+	for (param = desc; param->name; param++) {
+		/* Check for duplicate parameter names */
+		for (p2 = desc; p2 < param; p2++) {
+			if (strcmp(param->name, p2->name) == 0) {
+				if (is_flag(param) != is_flag(p2))
+					continue;
+				pr_err("VALIDATE %s: PARAM[%s]: Duplicate\n",
 				       name, param->name);
 				good = false;
 			}
 		}
-	} else {
-		if (enums) {
-			pr_err("VALIDATE %s: enum-type values, but no enum table\n",
-			       name);
-			good = false;
-			goto no_enums;
-		}
 	}
-
-no_enums:
 	return good;
 }
 #endif /* CONFIG_VALIDATE_FS_PARSER */