[PATCH v3 1/2] ovl: propagate ovl_fs to ovl_decode_real_fh and ovl_encode_real_fh

From: Pavel Tikhomirov
Date: Thu Sep 24 2020 - 12:38:23 EST


This will be used in next patch to be able to change uuid checks and
add uuid nullification based on ofs->config.index for a new "uuid=off"
mode.

CC: Amir Goldstein <amir73il@xxxxxxxxx>
CC: Vivek Goyal <vgoyal@xxxxxxxxxx>
CC: Miklos Szeredi <miklos@xxxxxxxxxx>
CC: linux-unionfs@xxxxxxxxxxxxxxx
CC: linux-kernel@xxxxxxxxxxxxxxx
Signed-off-by: Pavel Tikhomirov <ptikhomirov@xxxxxxxxxxxxx>
---
fs/overlayfs/copy_up.c | 22 ++++++++++++----------
fs/overlayfs/export.c | 10 ++++++----
fs/overlayfs/namei.c | 19 ++++++++++---------
fs/overlayfs/overlayfs.h | 14 ++++++++------
fs/overlayfs/util.c | 3 ++-
5 files changed, 38 insertions(+), 30 deletions(-)

diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c
index 955ecd4030f0..3380039036d6 100644
--- a/fs/overlayfs/copy_up.c
+++ b/fs/overlayfs/copy_up.c
@@ -275,7 +275,8 @@ int ovl_set_attr(struct dentry *upperdentry, struct kstat *stat)
return err;
}

-struct ovl_fh *ovl_encode_real_fh(struct dentry *real, bool is_upper)
+struct ovl_fh *ovl_encode_real_fh(struct ovl_fs *ofs, struct dentry *real,
+ bool is_upper)
{
struct ovl_fh *fh;
int fh_type, dwords;
@@ -328,8 +329,8 @@ struct ovl_fh *ovl_encode_real_fh(struct dentry *real, bool is_upper)
return ERR_PTR(err);
}

-int ovl_set_origin(struct dentry *dentry, struct dentry *lower,
- struct dentry *upper)
+int ovl_set_origin(struct ovl_fs *ofs, struct dentry *dentry,
+ struct dentry *lower, struct dentry *upper)
{
const struct ovl_fh *fh = NULL;
int err;
@@ -340,7 +341,7 @@ int ovl_set_origin(struct dentry *dentry, struct dentry *lower,
* up and a pure upper inode.
*/
if (ovl_can_decode_fh(lower->d_sb)) {
- fh = ovl_encode_real_fh(lower, false);
+ fh = ovl_encode_real_fh(ofs, lower, false);
if (IS_ERR(fh))
return PTR_ERR(fh);
}
@@ -362,7 +363,7 @@ static int ovl_set_upper_fh(struct ovl_fs *ofs, struct dentry *upper,
const struct ovl_fh *fh;
int err;

- fh = ovl_encode_real_fh(upper, true);
+ fh = ovl_encode_real_fh(ofs, upper, true);
if (IS_ERR(fh))
return PTR_ERR(fh);

@@ -380,6 +381,7 @@ static int ovl_set_upper_fh(struct ovl_fs *ofs, struct dentry *upper,
static int ovl_create_index(struct dentry *dentry, struct dentry *origin,
struct dentry *upper)
{
+ struct ovl_fs *ofs = OVL_FS(dentry->d_sb);
struct dentry *indexdir = ovl_indexdir(dentry->d_sb);
struct inode *dir = d_inode(indexdir);
struct dentry *index = NULL;
@@ -402,7 +404,7 @@ static int ovl_create_index(struct dentry *dentry, struct dentry *origin,
if (WARN_ON(ovl_test_flag(OVL_INDEX, d_inode(dentry))))
return -EIO;

- err = ovl_get_index_name(origin, &name);
+ err = ovl_get_index_name(ofs, origin, &name);
if (err)
return err;

@@ -411,7 +413,7 @@ static int ovl_create_index(struct dentry *dentry, struct dentry *origin,
if (IS_ERR(temp))
goto free_name;

- err = ovl_set_upper_fh(OVL_FS(dentry->d_sb), upper, temp);
+ err = ovl_set_upper_fh(ofs, upper, temp);
if (err)
goto out;

@@ -521,7 +523,7 @@ static int ovl_copy_up_inode(struct ovl_copy_up_ctx *c, struct dentry *temp)
* hard link.
*/
if (c->origin) {
- err = ovl_set_origin(c->dentry, c->lowerpath.dentry, temp);
+ err = ovl_set_origin(ofs, c->dentry, c->lowerpath.dentry, temp);
if (err)
return err;
}
@@ -700,7 +702,7 @@ static int ovl_copy_up_tmpfile(struct ovl_copy_up_ctx *c)
static int ovl_do_copy_up(struct ovl_copy_up_ctx *c)
{
int err;
- struct ovl_fs *ofs = c->dentry->d_sb->s_fs_info;
+ struct ovl_fs *ofs = OVL_FS(c->dentry->d_sb);
bool to_index = false;

/*
@@ -722,7 +724,7 @@ static int ovl_do_copy_up(struct ovl_copy_up_ctx *c)

if (to_index) {
c->destdir = ovl_indexdir(c->dentry->d_sb);
- err = ovl_get_index_name(c->lowerpath.dentry, &c->destname);
+ err = ovl_get_index_name(ofs, c->lowerpath.dentry, &c->destname);
if (err)
return err;
} else if (WARN_ON(!c->parent)) {
diff --git a/fs/overlayfs/export.c b/fs/overlayfs/export.c
index ed35be3fafc6..41ebf52f1bbc 100644
--- a/fs/overlayfs/export.c
+++ b/fs/overlayfs/export.c
@@ -211,7 +211,8 @@ static int ovl_check_encode_origin(struct dentry *dentry)
return 1;
}

-static int ovl_dentry_to_fid(struct dentry *dentry, u32 *fid, int buflen)
+static int ovl_dentry_to_fid(struct ovl_fs *ofs, struct dentry *dentry,
+ u32 *fid, int buflen)
{
struct ovl_fh *fh = NULL;
int err, enc_lower;
@@ -226,7 +227,7 @@ static int ovl_dentry_to_fid(struct dentry *dentry, u32 *fid, int buflen)
goto fail;

/* Encode an upper or lower file handle */
- fh = ovl_encode_real_fh(enc_lower ? ovl_dentry_lower(dentry) :
+ fh = ovl_encode_real_fh(ofs, enc_lower ? ovl_dentry_lower(dentry) :
ovl_dentry_upper(dentry), !enc_lower);
if (IS_ERR(fh))
return PTR_ERR(fh);
@@ -249,6 +250,7 @@ static int ovl_dentry_to_fid(struct dentry *dentry, u32 *fid, int buflen)
static int ovl_encode_fh(struct inode *inode, u32 *fid, int *max_len,
struct inode *parent)
{
+ struct ovl_fs *ofs = OVL_FS(inode->i_sb);
struct dentry *dentry;
int bytes, buflen = *max_len << 2;

@@ -260,7 +262,7 @@ static int ovl_encode_fh(struct inode *inode, u32 *fid, int *max_len,
if (WARN_ON(!dentry))
return FILEID_INVALID;

- bytes = ovl_dentry_to_fid(dentry, fid, buflen);
+ bytes = ovl_dentry_to_fid(ofs, dentry, fid, buflen);
dput(dentry);
if (bytes <= 0)
return FILEID_INVALID;
@@ -680,7 +682,7 @@ static struct dentry *ovl_upper_fh_to_d(struct super_block *sb,
if (!ovl_upper_mnt(ofs))
return ERR_PTR(-EACCES);

- upper = ovl_decode_real_fh(fh, ovl_upper_mnt(ofs), true);
+ upper = ovl_decode_real_fh(ofs, fh, ovl_upper_mnt(ofs), true);
if (IS_ERR_OR_NULL(upper))
return upper;

diff --git a/fs/overlayfs/namei.c b/fs/overlayfs/namei.c
index a6162c4076db..f058bf8e8b87 100644
--- a/fs/overlayfs/namei.c
+++ b/fs/overlayfs/namei.c
@@ -150,8 +150,8 @@ static struct ovl_fh *ovl_get_fh(struct ovl_fs *ofs, struct dentry *dentry,
goto out;
}

-struct dentry *ovl_decode_real_fh(struct ovl_fh *fh, struct vfsmount *mnt,
- bool connected)
+struct dentry *ovl_decode_real_fh(struct ovl_fs *ofs, struct ovl_fh *fh,
+ struct vfsmount *mnt, bool connected)
{
struct dentry *real;
int bytes;
@@ -354,7 +354,7 @@ int ovl_check_origin_fh(struct ovl_fs *ofs, struct ovl_fh *fh, bool connected,
ofs->layers[i].fs->bad_uuid)
continue;

- origin = ovl_decode_real_fh(fh, ofs->layers[i].mnt,
+ origin = ovl_decode_real_fh(ofs, fh, ofs->layers[i].mnt,
connected);
if (origin)
break;
@@ -450,7 +450,7 @@ int ovl_verify_set_fh(struct ovl_fs *ofs, struct dentry *dentry,
struct ovl_fh *fh;
int err;

- fh = ovl_encode_real_fh(real, is_upper);
+ fh = ovl_encode_real_fh(ofs, real, is_upper);
err = PTR_ERR(fh);
if (IS_ERR(fh)) {
fh = NULL;
@@ -488,7 +488,7 @@ struct dentry *ovl_index_upper(struct ovl_fs *ofs, struct dentry *index)
if (IS_ERR_OR_NULL(fh))
return ERR_CAST(fh);

- upper = ovl_decode_real_fh(fh, ovl_upper_mnt(ofs), true);
+ upper = ovl_decode_real_fh(ofs, fh, ovl_upper_mnt(ofs), true);
kfree(fh);

if (IS_ERR_OR_NULL(upper))
@@ -640,12 +640,13 @@ static int ovl_get_index_name_fh(struct ovl_fh *fh, struct qstr *name)
* index dir was cleared. Either way, that index cannot be used to indentify
* the overlay inode.
*/
-int ovl_get_index_name(struct dentry *origin, struct qstr *name)
+int ovl_get_index_name(struct ovl_fs *ofs, struct dentry *origin,
+ struct qstr *name)
{
struct ovl_fh *fh;
int err;

- fh = ovl_encode_real_fh(origin, false);
+ fh = ovl_encode_real_fh(ofs, origin, false);
if (IS_ERR(fh))
return PTR_ERR(fh);

@@ -694,7 +695,7 @@ struct dentry *ovl_lookup_index(struct ovl_fs *ofs, struct dentry *upper,
bool is_dir = d_is_dir(origin);
int err;

- err = ovl_get_index_name(origin, &name);
+ err = ovl_get_index_name(ofs, origin, &name);
if (err)
return ERR_PTR(err);

@@ -805,7 +806,7 @@ static int ovl_fix_origin(struct ovl_fs *ofs, struct dentry *dentry,
if (err)
return err;

- err = ovl_set_origin(dentry, lower, upper);
+ err = ovl_set_origin(ofs, dentry, lower, upper);
if (!err)
err = ovl_set_impure(dentry->d_parent, upper->d_parent);

diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h
index 7bce2469fe55..b56b5f46f224 100644
--- a/fs/overlayfs/overlayfs.h
+++ b/fs/overlayfs/overlayfs.h
@@ -383,8 +383,8 @@ static inline int ovl_check_fh_len(struct ovl_fh *fh, int fh_len)
return ovl_check_fb_len(&fh->fb, fh_len - OVL_FH_WIRE_OFFSET);
}

-struct dentry *ovl_decode_real_fh(struct ovl_fh *fh, struct vfsmount *mnt,
- bool connected);
+struct dentry *ovl_decode_real_fh(struct ovl_fs *ofs, struct ovl_fh *fh,
+ struct vfsmount *mnt, bool connected);
int ovl_check_origin_fh(struct ovl_fs *ofs, struct ovl_fh *fh, bool connected,
struct dentry *upperdentry, struct ovl_path **stackp);
int ovl_verify_set_fh(struct ovl_fs *ofs, struct dentry *dentry,
@@ -392,7 +392,8 @@ int ovl_verify_set_fh(struct ovl_fs *ofs, struct dentry *dentry,
bool set);
struct dentry *ovl_index_upper(struct ovl_fs *ofs, struct dentry *index);
int ovl_verify_index(struct ovl_fs *ofs, struct dentry *index);
-int ovl_get_index_name(struct dentry *origin, struct qstr *name);
+int ovl_get_index_name(struct ovl_fs *ofs, struct dentry *origin,
+ struct qstr *name);
struct dentry *ovl_get_index_fh(struct ovl_fs *ofs, struct ovl_fh *fh);
struct dentry *ovl_lookup_index(struct ovl_fs *ofs, struct dentry *upper,
struct dentry *origin, bool verify);
@@ -511,9 +512,10 @@ int ovl_maybe_copy_up(struct dentry *dentry, int flags);
int ovl_copy_xattr(struct super_block *sb, struct dentry *old,
struct dentry *new);
int ovl_set_attr(struct dentry *upper, struct kstat *stat);
-struct ovl_fh *ovl_encode_real_fh(struct dentry *real, bool is_upper);
-int ovl_set_origin(struct dentry *dentry, struct dentry *lower,
- struct dentry *upper);
+struct ovl_fh *ovl_encode_real_fh(struct ovl_fs *ofs, struct dentry *real,
+ bool is_upper);
+int ovl_set_origin(struct ovl_fs *ofs, struct dentry *dentry,
+ struct dentry *lower, struct dentry *upper);

/* export.c */
extern const struct export_operations ovl_export_operations;
diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c
index 23f475627d07..44b4b62a8ac8 100644
--- a/fs/overlayfs/util.c
+++ b/fs/overlayfs/util.c
@@ -716,6 +716,7 @@ bool ovl_need_index(struct dentry *dentry)
/* Caller must hold OVL_I(inode)->lock */
static void ovl_cleanup_index(struct dentry *dentry)
{
+ struct ovl_fs *ofs = OVL_FS(dentry->d_sb);
struct dentry *indexdir = ovl_indexdir(dentry->d_sb);
struct inode *dir = indexdir->d_inode;
struct dentry *lowerdentry = ovl_dentry_lower(dentry);
@@ -725,7 +726,7 @@ static void ovl_cleanup_index(struct dentry *dentry)
struct qstr name = { };
int err;

- err = ovl_get_index_name(lowerdentry, &name);
+ err = ovl_get_index_name(ofs, lowerdentry, &name);
if (err)
goto fail;

--
2.26.2