[PATCH 11/15] Add ngnfs_dir_mkdir() and debugfs command

[Valerie Aurora]

Makes a directory of the specified name in the current working
directory in debugfs.

Signed-off-by: Valerie Aurora <val at versity.com>
---
 cli/debugfs.c | 21 +++++++++++++++++++++
 shared/dir.c  | 43 ++++++++++++++++++++++++++++++++++++++++---
 shared/dir.h  |  2 ++
 3 files changed, 63 insertions(+), 3 deletions(-)

diff --git a/cli/debugfs.c b/cli/debugfs.c
index 0c0914c..3494070 100644
--- a/cli/debugfs.c
+++ b/cli/debugfs.c
@@ -118,6 +118,26 @@ static void cmd_lookup(struct debugfs_context *ctx, int argc, char **argv)
 	       lent.ig.gen);
 }
 
+static void cmd_mkdir(struct debugfs_context *ctx, int argc, char **argv)
+{
+	int ret;
+
+	if (argc != 2) {
+		printf("must have one, and only one, directory name to create\n");
+		return;
+	}
+
+	ret = ngnfs_dir_mkdir(ctx->nfi, &ctx->cwd_ig, 0755, argv[1], strlen(argv[1]));
+	if (ret == -EEXIST) {
+		printf("mkdir: file exists\n");
+		return;
+	}
+	if (ret < 0) {
+		log("mkdir error: "ENOF"\n", ENOA(-ret));
+		return;
+	}
+}
+
 static void cmd_mkfs(struct debugfs_context *ctx, int argc, char **argv)
 {
 	int ret;
@@ -268,6 +288,7 @@ static struct command {
 	{ "cd", cmd_cd, },
 	{ "create", cmd_create, },
 	{ "lookup", cmd_lookup, },
+	{ "mkdir", cmd_mkdir, },
 	{ "mkfs", cmd_mkfs, },
 	{ "quit", cmd_quit, },
 	{ "readdir", cmd_readdir, },
diff --git a/shared/dir.c b/shared/dir.c
index 074f998..ebeea01 100644
--- a/shared/dir.c
+++ b/shared/dir.c
@@ -261,11 +261,24 @@ static int insert_dirent(struct ngnfs_fs_info *nfi, struct ngnfs_transaction *tx
 				      &last, insert_dirent_wr, da);
 }
 
+/*
+ * Prevent creation of "." and "..", with appropriate error return codes.
+ */
+static int check_create_dots(u64 hash, mode_t mode)
+{
+	if ((hash != NGNFS_DIRENT_DOT_HASH) && (hash != NGNFS_DIRENT_DOT_DOT_HASH))
+		return 0;
+
+	if (S_ISDIR(mode))
+		return -EEXIST;
+	else
+		return -EISDIR;
+}
 
 /*
  * Allocate a new inode and add a directory entry referencing it.
  */
-int ngnfs_dir_create(struct ngnfs_fs_info *nfi, struct ngnfs_inode_ino_gen *dir, umode_t mode,
+static int do_create(struct ngnfs_fs_info *nfi, struct ngnfs_inode_ino_gen *dir, umode_t mode,
 		     char *name, size_t name_len)
 {
 	struct {
@@ -273,6 +286,8 @@ int ngnfs_dir_create(struct ngnfs_fs_info *nfi, struct ngnfs_inode_ino_gen *dir,
 		struct ngnfs_inode_txn_ref dir;
 		struct ngnfs_inode_txn_ref inode;
 		struct ngnfs_inode_ino_gen ig;
+		struct ngnfs_inode_ino_gen *parent_ig;
+		int nlink;
 		u64 nsec;
 		struct dirent_args da;
 	} *op;
@@ -286,13 +301,23 @@ int ngnfs_dir_create(struct ngnfs_fs_info *nfi, struct ngnfs_inode_ino_gen *dir,
 
 	ngnfs_txn_init(&op->txn);
 	op->nsec = ktime_to_ns(ktime_get_real());
-	init_dirent_args(&op->da, name, name_len, mode | S_IFREG);
+	if (S_ISDIR(mode)) {
+		op->nlink = 2;
+		op->parent_ig = dir;
+	} else {
+		op->nlink = 1;
+		op->parent_ig = NULL;
+	}
+
+	init_dirent_args(&op->da, name, name_len, mode);
 
 	do {
 		ret = ngnfs_inode_get(nfi, &op->txn, NBF_WRITE, dir, &op->dir)			?:
 		      check_ifmt(op->dir.ninode, S_IFDIR, -ENOTDIR)				?:
+		      check_create_dots(op->da.hash, mode)					?:
 		      ngnfs_inode_alloc(nfi, &op->txn, &op->ig, &op->inode)			?:
-		      ngnfs_inode_init(&op->inode, &op->ig, 1, mode | S_IFREG, op->nsec, NULL)	?:
+		      ngnfs_inode_init(&op->inode, &op->ig, op->nlink, mode, op->nsec,
+				       op->parent_ig)						?:
 		      update_dirent_args_ig(&op->da, &op->ig)					?:
 		      insert_dirent(nfi, &op->txn, &op->dir, &op->da)				?:
 		      update_dir(op->dir.tblk, op->dir.ninode, &op->da, 1);
@@ -305,6 +330,18 @@ out:
 	return ret;
 }
 
+int ngnfs_dir_create(struct ngnfs_fs_info *nfi, struct ngnfs_inode_ino_gen *dir, umode_t mode,
+		     char *name, size_t name_len)
+{
+	return do_create(nfi, dir, mode | S_IFREG, name, name_len);
+}
+
+int ngnfs_dir_mkdir(struct ngnfs_fs_info *nfi, struct ngnfs_inode_ino_gen *dir, umode_t mode,
+		    char *name, size_t name_len)
+{
+	return do_create(nfi, dir, mode | S_IFDIR, name, name_len);
+}
+
 struct readdir_args {
 	struct ngnfs_readdir_entry *ent;
 	size_t size;
diff --git a/shared/dir.h b/shared/dir.h
index 178f53e..5dd57dd 100644
--- a/shared/dir.h
+++ b/shared/dir.h
@@ -8,6 +8,8 @@
 
 int ngnfs_dir_create(struct ngnfs_fs_info *nfi, struct ngnfs_inode_ino_gen *dir, umode_t mode,
 		     char *name, size_t name_len);
+int ngnfs_dir_mkdir(struct ngnfs_fs_info *nfi, struct ngnfs_inode_ino_gen *dir, umode_t mode,
+		    char *name, size_t name_len);
 
 /*
  * Readdir fills the buffer with entries.  The start of the buffer must
-- 
2.48.1