From: Erez Zadok <ezk@cs.sunysb.edu>
Date: Wed, 27 Nov 2013 03:01:34 +0000 (-0500)
Subject: Unionfs: port to 3.11
X-Git-Url: https://git.fsl.cs.sunysb.edu/?a=commitdiff_plain;h=f7af56b881de3e81996bedcc43565b017f3beb20;p=unionfs-3.13.y.git

Unionfs: port to 3.11

Readdir VFS interface overhauled between 3.10 and 3.11.

Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
---

diff --git a/fs/unionfs/dirfops.c b/fs/unionfs/dirfops.c
index 72a9c1a04a1..7b2f3cfd8af 100644
--- a/fs/unionfs/dirfops.c
+++ b/fs/unionfs/dirfops.c
@@ -26,20 +26,21 @@ static void verify_rdstate_offset(struct unionfs_dir_state *rdstate)
 }
 
 struct unionfs_getdents_callback {
+	struct dir_context ctx; /* must be first field */
+	struct dir_context *caller;
 	struct unionfs_dir_state *rdstate;
-	void *dirent;
 	int entries_written;
 	int filldir_called;
 	int filldir_error;
-	filldir_t filldir;
 	struct super_block *sb;
 };
 
 /* based on generic filldir in fs/readir.c */
-static int unionfs_filldir(void *dirent, const char *oname, int namelen,
+static int unionfs_filldir(void *__buf, const char *oname, int namelen,
 			   loff_t offset, u64 ino, unsigned int d_type)
 {
-	struct unionfs_getdents_callback *buf = dirent;
+	struct unionfs_getdents_callback *buf =
+		(struct unionfs_getdents_callback *) __buf;
 	struct filldir_node *found = NULL;
 	int err = 0;
 	int is_whiteout;
@@ -63,11 +64,12 @@ static int unionfs_filldir(void *dirent, const char *oname, int namelen,
 
 	/* if 'name' isn't a whiteout, filldir it. */
 	if (!is_whiteout) {
+#if 0
+		// XXX: old code, not sure if needed
 		off_t pos = rdstate2offset(buf->rdstate);
-		u64 unionfs_ino = ino;
-
-		err = buf->filldir(buf->dirent, name, namelen, pos,
-				   unionfs_ino, d_type);
+#endif
+		buf->caller->pos = buf->ctx.pos;
+		err = !dir_emit(buf->caller, name, namelen, ino, d_type);
 		buf->rdstate->offset++;
 		verify_rdstate_offset(buf->rdstate);
 	}
@@ -89,14 +91,16 @@ out:
 	return err;
 }
 
-static int unionfs_readdir(struct file *file, void *dirent, filldir_t filldir)
+static int unionfs_readdir(struct file *file, struct dir_context *ctx)
 {
 	int err = 0;
 	struct file *lower_file = NULL;
 	struct dentry *dentry = file->f_path.dentry;
 	struct dentry *parent;
 	struct inode *inode = NULL;
-	struct unionfs_getdents_callback buf;
+	struct unionfs_getdents_callback buf = {
+		.ctx.actor = unionfs_filldir,
+	};
 	struct unionfs_dir_state *uds;
 	int bend;
 	loff_t offset;
@@ -141,10 +145,9 @@ static int unionfs_readdir(struct file *file, void *dirent, filldir_t filldir)
 		buf.filldir_called = 0;
 		buf.filldir_error = 0;
 		buf.entries_written = 0;
-		buf.dirent = dirent;
-		buf.filldir = filldir;
 		buf.rdstate = uds;
 		buf.sb = inode->i_sb;
+		buf.caller = ctx;
 
 		/* Read starting from where we last left off. */
 		offset = vfs_llseek(lower_file, uds->dirpos, SEEK_SET);
@@ -152,7 +155,10 @@ static int unionfs_readdir(struct file *file, void *dirent, filldir_t filldir)
 			err = offset;
 			goto out;
 		}
-		err = vfs_readdir(lower_file, unionfs_filldir, &buf);
+
+		lower_file->f_pos = ctx->pos;
+		err = iterate_dir(lower_file, &buf.ctx);
+		ctx->pos = buf.ctx.pos;
 
 		/* Save the position for when we continue. */
 		offset = vfs_llseek(lower_file, 0, SEEK_CUR);
@@ -183,9 +189,9 @@ static int unionfs_readdir(struct file *file, void *dirent, filldir_t filldir)
 		UNIONFS_I(inode)->hashsize = uds->hashentries;
 		free_rdstate(uds);
 		UNIONFS_F(file)->rdstate = NULL;
-		file->f_pos = DIREOF;
+		ctx->pos = DIREOF;
 	} else {
-		file->f_pos = rdstate2offset(uds);
+		ctx->pos = rdstate2offset(uds);
 	}
 
 out:
@@ -292,7 +298,7 @@ out:
 struct file_operations unionfs_dir_fops = {
 	.llseek		= unionfs_dir_llseek,
 	.read		= generic_read_dir,
-	.readdir	= unionfs_readdir,
+	.iterate	= unionfs_readdir,
 	.unlocked_ioctl	= unionfs_ioctl,
 	.open		= unionfs_open,
 	.release	= unionfs_file_release,
diff --git a/fs/unionfs/dirhelper.c b/fs/unionfs/dirhelper.c
index bd1c1fcf324..08d12eca39a 100644
--- a/fs/unionfs/dirhelper.c
+++ b/fs/unionfs/dirhelper.c
@@ -22,6 +22,7 @@
 #define RD_CHECK_EMPTY 1
 /* The callback structure for check_empty. */
 struct unionfs_rdutil_callback {
+	struct dir_context ctx; // NEW: must be first in callback struct
 	int err;
 	int filldir_called;
 	struct unionfs_dir_state *rdstate;
@@ -76,7 +77,9 @@ int check_empty(struct dentry *dentry, struct dentry *parent,
 	struct vfsmount *mnt;
 	struct super_block *sb;
 	struct file *lower_file;
-	struct unionfs_rdutil_callback *buf = NULL;
+	struct unionfs_rdutil_callback buf = {
+		.ctx.actor = readdir_util_callback,
+	};
 	int bindex, bstart, bend, bopaque;
 	struct path path;
 
@@ -95,15 +98,12 @@ int check_empty(struct dentry *dentry, struct dentry *parent,
 	if (0 <= bopaque && bopaque < bend)
 		bend = bopaque;
 
-	buf = kmalloc(sizeof(struct unionfs_rdutil_callback), GFP_KERNEL);
-	if (unlikely(!buf)) {
-		err = -ENOMEM;
-		goto out;
-	}
-	buf->err = 0;
-	buf->mode = RD_CHECK_EMPTY;
-	buf->rdstate = alloc_rdstate(dentry->d_inode, bstart);
-	if (unlikely(!buf->rdstate)) {
+	buf.err = 0;
+	buf.filldir_called = 0;
+	buf.mode = RD_CHECK_EMPTY;
+	buf.ctx.pos = 0; /* XXX: needed?! */
+	buf.rdstate = alloc_rdstate(dentry->d_inode, bstart);
+	if (unlikely(!buf.rdstate)) {
 		err = -ENOMEM;
 		goto out;
 	}
@@ -132,13 +132,12 @@ int check_empty(struct dentry *dentry, struct dentry *parent,
 		}
 
 		do {
-			buf->filldir_called = 0;
-			buf->rdstate->bindex = bindex;
-			err = vfs_readdir(lower_file,
-					  readdir_util_callback, buf);
-			if (buf->err)
-				err = buf->err;
-		} while ((err >= 0) && buf->filldir_called);
+			buf.filldir_called = 0;
+			buf.rdstate->bindex = bindex;
+			err = iterate_dir(lower_file, &buf.ctx);
+			if (buf.err)
+				err = buf.err;
+		} while ((err >= 0) && buf.filldir_called);
 
 		/* fput calls dput for lower_dentry */
 		fput(lower_file);
@@ -149,14 +148,10 @@ int check_empty(struct dentry *dentry, struct dentry *parent,
 	}
 
 out:
-	if (buf) {
-		if (namelist && !err)
-			*namelist = buf->rdstate;
-		else if (buf->rdstate)
-			free_rdstate(buf->rdstate);
-		kfree(buf);
-	}
-
+	if (namelist && !err)
+		*namelist = buf.rdstate;
+	else if (buf.rdstate)
+		free_rdstate(buf.rdstate);
 
 	return err;
 }
diff --git a/fs/unionfs/file.c b/fs/unionfs/file.c
index 8a04063930e..f67db0ab6e6 100644
--- a/fs/unionfs/file.c
+++ b/fs/unionfs/file.c
@@ -85,8 +85,7 @@ out:
 	return err;
 }
 
-static int unionfs_file_readdir(struct file *file, void *dirent,
-				filldir_t filldir)
+static int unionfs_file_readdir(struct file *file, struct dir_context *ctx)
 {
 	return -ENOTDIR;
 }
@@ -371,7 +370,7 @@ struct file_operations unionfs_main_fops = {
 	.llseek		= generic_file_llseek,
 	.read		= unionfs_read,
 	.write		= unionfs_write,
-	.readdir	= unionfs_file_readdir,
+	.iterate	= unionfs_file_readdir,
 	.unlocked_ioctl	= unionfs_ioctl,
 #ifdef CONFIG_COMPAT
 	.compat_ioctl	= unionfs_ioctl,