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, 27 insertions, 52 deletions

diff --git a/fs/fs_context.c b/fs/fs_context.c
index 138b5b4d621d..fc9f6ef93b55 100644
--- a/fs/fs_context.c
+++ b/fs/fs_context.c
@@ -45,6 +45,7 @@ static const struct constant_table common_set_sb_flag[] = {
 	{ "posixacl",	SB_POSIXACL },
 	{ "ro",		SB_RDONLY },
 	{ "sync",	SB_SYNCHRONOUS },
+	{ },
 };
 
 static const struct constant_table common_clear_sb_flag[] = {
@@ -53,6 +54,7 @@ static const struct constant_table common_clear_sb_flag[] = {
 	{ "nomand",	SB_MANDLOCK },
 	{ "rw",		SB_RDONLY },
 	{ "silent",	SB_SILENT },
+	{ },
 };
 
 static const char *const forbidden_sb_flag[] = {
@@ -175,14 +177,15 @@ int vfs_parse_fs_string(struct fs_context *fc, const char *key,
 
 	struct fs_parameter param = {
 		.key	= key,
-		.type	= fs_value_is_string,
+		.type	= fs_value_is_flag,
 		.size	= v_size,
 	};
 
-	if (v_size > 0) {
+	if (value) {
 		param.string = kmemdup_nul(value, v_size, GFP_KERNEL);
 		if (!param.string)
 			return -ENOMEM;
+		param.type = fs_value_is_string;
 	}
 
 	ret = vfs_parse_fs_param(fc, &param);
@@ -268,6 +271,7 @@ static struct fs_context *alloc_fs_context(struct file_system_type *fs_type,
 	fc->fs_type	= get_filesystem(fs_type);
 	fc->cred	= get_current_cred();
 	fc->net_ns	= get_net(current->nsproxy->net_ns);
+	fc->log.prefix	= fs_type->name;
 
 	mutex_init(&fc->uapi_mutex);
 
@@ -361,8 +365,8 @@ struct fs_context *vfs_dup_fs_context(struct fs_context *src_fc)
 	get_net(fc->net_ns);
 	get_user_ns(fc->user_ns);
 	get_cred(fc->cred);
-	if (fc->log)
-		refcount_inc(&fc->log->usage);
+	if (fc->log.log)
+		refcount_inc(&fc->log.log->usage);
 
 	/* Can't call put until we've called ->dup */
 	ret = fc->ops->dup(fc, src_fc);
@@ -385,64 +389,33 @@ EXPORT_SYMBOL(vfs_dup_fs_context);
  * @fc: The filesystem context to log to.
  * @fmt: The format of the buffer.
  */
-void logfc(struct fs_context *fc, const char *fmt, ...)
+void logfc(struct fc_log *log, const char *prefix, char level, const char *fmt, ...)
 {
-	static const char store_failure[] = "OOM: Can't store error string";
-	struct fc_log *log = fc ? fc->log : NULL;
-	const char *p;
 	va_list va;
-	char *q;
-	u8 freeable;
+	struct va_format vaf = {.fmt = fmt, .va = &va};
 
 	va_start(va, fmt);
-	if (!strchr(fmt, '%')) {
-		p = fmt;
-		goto unformatted_string;
-	}
-	if (strcmp(fmt, "%s") == 0) {
-		p = va_arg(va, const char *);
-		goto unformatted_string;
-	}
-
-	q = kvasprintf(GFP_KERNEL, fmt, va);
-copied_string:
-	if (!q)
-		goto store_failure;
-	freeable = 1;
-	goto store_string;
-
-unformatted_string:
-	if ((unsigned long)p >= (unsigned long)__start_rodata &&
-	    (unsigned long)p <  (unsigned long)__end_rodata)
-		goto const_string;
-	if (log && within_module_core((unsigned long)p, log->owner))
-		goto const_string;
-	q = kstrdup(p, GFP_KERNEL);
-	goto copied_string;
-
-store_failure:
-	p = store_failure;
-const_string:
-	q = (char *)p;
-	freeable = 0;
-store_string:
 	if (!log) {
-		switch (fmt[0]) {
+		switch (level) {
 		case 'w':
-			printk(KERN_WARNING "%s\n", q + 2);
+			printk(KERN_WARNING "%s%s%pV\n", prefix ? prefix : "",
+						prefix ? ": " : "", &vaf);
 			break;
 		case 'e':
-			printk(KERN_ERR "%s\n", q + 2);
+			printk(KERN_ERR "%s%s%pV\n", prefix ? prefix : "",
+						prefix ? ": " : "", &vaf);
 			break;
 		default:
-			printk(KERN_NOTICE "%s\n", q + 2);
+			printk(KERN_NOTICE "%s%s%pV\n", prefix ? prefix : "",
+						prefix ? ": " : "", &vaf);
 			break;
 		}
-		if (freeable)
-			kfree(q);
 	} else {
 		unsigned int logsize = ARRAY_SIZE(log->buffer);
 		u8 index;
+		char *q = kasprintf(GFP_KERNEL, "%c %s%s%pV\n", level,
+						prefix ? prefix : "",
+						prefix ? ": " : "", &vaf);
 
 		index = log->head & (logsize - 1);
 		BUILD_BUG_ON(sizeof(log->head) != sizeof(u8) ||
@@ -454,9 +427,11 @@ store_string:
 			log->tail++;
 		}
 
-		log->buffer[index] = q;
-		log->need_free &= ~(1 << index);
-		log->need_free |= freeable << index;
+		log->buffer[index] = q ? q : "OOM: Can't store error string";
+		if (q)
+			log->need_free |= 1 << index;
+		else
+			log->need_free &= ~(1 << index);
 		log->head++;
 	}
 	va_end(va);
@@ -468,12 +443,12 @@ EXPORT_SYMBOL(logfc);
  */
 static void put_fc_log(struct fs_context *fc)
 {
-	struct fc_log *log = fc->log;
+	struct fc_log *log = fc->log.log;
 	int i;
 
 	if (log) {
 		if (refcount_dec_and_test(&log->usage)) {
-			fc->log = NULL;
+			fc->log.log = NULL;
 			for (i = 0; i <= 7; i++)
 				if (log->need_free & (1 << i))
 					kfree(log->buffer[i]);