Re: [PATCH v4 1/2] ovl: propagate ovl_fs to ovl_decode_real_fh and ovl_encode_real_fh

From: Amir Goldstein
Date: Fri Sep 25 2020 - 12:37:46 EST


On Fri, Sep 25, 2020 at 11:35 AM Pavel Tikhomirov
<ptikhomirov@xxxxxxxxxxxxx> wrote:
>
> 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>
Reviewed-by: Amir Goldstein <amir73il@xxxxxxxxx>

> ---
> 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
>