[PATCH 15/38] fallthru: jffs2 fallthru support

From: Valerie Aurora
Date: Tue Jun 15 2010 - 14:49:17 EST


From: Felix Fietkau <nbd@xxxxxxxxxxx>

Add support for fallthru dentries to jffs2.

Cc: David Woodhouse <dwmw2@xxxxxxxxxxxxx>
Cc: linux-mtd@xxxxxxxxxxxxxxxxxxx
Signed-off-by: Felix Fietkau <nbd@xxxxxxxxxxx>
Signed-off-by: Valerie Aurora <vaurora@xxxxxxxxxx>
---
fs/jffs2/dir.c | 36 +++++++++++++++++++++++++++++++++---
include/linux/jffs2.h | 6 ++++++
2 files changed, 39 insertions(+), 3 deletions(-)

diff --git a/fs/jffs2/dir.c b/fs/jffs2/dir.c
index c259193..98397b3 100644
--- a/fs/jffs2/dir.c
+++ b/fs/jffs2/dir.c
@@ -35,6 +35,7 @@ static int jffs2_rename (struct inode *, struct dentry *,
struct inode *, struct dentry *);

static int jffs2_whiteout (struct inode *, struct dentry *, struct dentry *);
+static int jffs2_fallthru (struct inode *, struct dentry *);

const struct file_operations jffs2_dir_operations =
{
@@ -59,6 +60,7 @@ const struct inode_operations jffs2_dir_inode_operations =
.rename = jffs2_rename,
.check_acl = jffs2_check_acl,
.whiteout = jffs2_whiteout,
+ .fallthru = jffs2_fallthru,
.setattr = jffs2_setattr,
.setxattr = jffs2_setxattr,
.getxattr = jffs2_getxattr,
@@ -103,10 +105,14 @@ static struct dentry *jffs2_lookup(struct inode *dir_i, struct dentry *target,
}
if (fd) {
spin_lock(&target->d_lock);
- if (fd->type == DT_WHT)
+ switch (fd->type) {
+ case DT_WHT:
target->d_flags |= DCACHE_WHITEOUT;
- else
+ case JFFS2_DT_FALLTHRU:
+ target->d_flags |= DCACHE_FALLTHRU;
+ default:
ino = fd->ino;
+ }
spin_unlock(&target->d_lock);
}
mutex_unlock(&dir_f->sem);
@@ -164,7 +170,10 @@ static int jffs2_readdir(struct file *filp, void *dirent, filldir_t filldir)
fd->name, fd->ino, fd->type, curofs, offset));
continue;
}
- if (!fd->ino) {
+ if (fd->type == JFFS2_DT_FALLTHRU)
+ /* XXX Should really do a lookup for the real inode number here */
+ fd->ino = 100;
+ else if (!fd->ino && (fd->type != DT_WHT)) {
D2(printk(KERN_DEBUG "Skipping deletion dirent \"%s\"\n", fd->name));
offset++;
continue;
@@ -793,6 +802,26 @@ static int jffs2_mknod (struct inode *dir_i, struct dentry *dentry, int mode, de
return 0;
}

+static int jffs2_fallthru (struct inode *dir, struct dentry *dentry)
+{
+ struct jffs2_sb_info *c = JFFS2_SB_INFO(dir->i_sb);
+ uint32_t now;
+ int ret;
+
+ now = get_seconds();
+ ret = jffs2_do_link(c, JFFS2_INODE_INFO(dir), 0, DT_UNKNOWN,
+ dentry->d_name.name, dentry->d_name.len, now);
+ if (ret)
+ return ret;
+
+ d_instantiate(dentry, NULL);
+ spin_lock(&dentry->d_lock);
+ dentry->d_flags |= DCACHE_FALLTHRU;
+ spin_unlock(&dentry->d_lock);
+
+ return 0;
+}
+
static int jffs2_whiteout (struct inode *dir, struct dentry *old_dentry,
struct dentry *new_dentry)
{
@@ -825,6 +854,7 @@ static int jffs2_whiteout (struct inode *dir, struct dentry *old_dentry,
return ret;

spin_lock(&new_dentry->d_lock);
+ new_dentry->d_flags &= ~DCACHE_FALLTHRU;
new_dentry->d_flags |= DCACHE_WHITEOUT;
spin_unlock(&new_dentry->d_lock);
d_add(new_dentry, NULL);
diff --git a/include/linux/jffs2.h b/include/linux/jffs2.h
index 65533bb..dbe8c93 100644
--- a/include/linux/jffs2.h
+++ b/include/linux/jffs2.h
@@ -114,6 +114,12 @@ struct jffs2_unknown_node
jint32_t hdr_crc;
};

+/*
+ * Non-standard directory entry type(s), for on-disk use
+ */
+
+#define JFFS2_DT_FALLTHRU (DT_WHT + 1)
+
struct jffs2_raw_dirent
{
jint16_t magic;
--
1.6.3.3

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