diff options
Diffstat (limited to 'fs/overlayfs/super.c')
| -rw-r--r-- | fs/overlayfs/super.c | 26 |
1 files changed, 22 insertions, 4 deletions
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c index 7d97d30cad39..d7284444f404 100644 --- a/fs/overlayfs/super.c +++ b/fs/overlayfs/super.c @@ -17,6 +17,7 @@ #include <linux/statfs.h> #include <linux/seq_file.h> #include <linux/posix_acl_xattr.h> +#include <linux/exportfs.h> #include "overlayfs.h" MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>"); @@ -701,6 +702,7 @@ static int ovl_check_namelen(struct path *path, struct ovl_fs *ofs, static int ovl_lower_dir(const char *name, struct path *path, struct ovl_fs *ofs, int *stack_depth, bool *remote) { + int fh_type; int err; err = ovl_mount_dir_noesc(name, path); @@ -720,15 +722,19 @@ static int ovl_lower_dir(const char *name, struct path *path, * The inodes index feature and NFS export need to encode and decode * file handles, so they require that all layers support them. */ + fh_type = ovl_can_decode_fh(path->dentry->d_sb); if ((ofs->config.nfs_export || - (ofs->config.index && ofs->config.upperdir)) && - !ovl_can_decode_fh(path->dentry->d_sb)) { + (ofs->config.index && ofs->config.upperdir)) && !fh_type) { ofs->config.index = false; ofs->config.nfs_export = false; pr_warn("overlayfs: fs on '%s' does not support file handles, falling back to index=off,nfs_export=off.\n", name); } + /* Check if lower fs has 32bit inode numbers */ + if (fh_type != FILEID_INO32_GEN) + ofs->xino_bits = 0; + return 0; out_put: @@ -952,6 +958,7 @@ static int ovl_make_workdir(struct ovl_fs *ofs, struct path *workpath) { struct vfsmount *mnt = ofs->upper_mnt; struct dentry *temp; + int fh_type; int err; err = mnt_want_write(mnt); @@ -1001,12 +1008,16 @@ static int ovl_make_workdir(struct ovl_fs *ofs, struct path *workpath) } /* Check if upper/work fs supports file handles */ - if (ofs->config.index && - !ovl_can_decode_fh(ofs->workdir->d_sb)) { + fh_type = ovl_can_decode_fh(ofs->workdir->d_sb); + if (ofs->config.index && !fh_type) { ofs->config.index = false; pr_warn("overlayfs: upper fs does not support file handles, falling back to index=off.\n"); } + /* Check if upper fs has 32bit inode numbers */ + if (fh_type != FILEID_INO32_GEN) + ofs->xino_bits = 0; + /* NFS export of r/w mount depends on index */ if (ofs->config.nfs_export && !ofs->config.index) { pr_warn("overlayfs: NFS export requires \"index=on\", falling back to nfs_export=off.\n"); @@ -1185,6 +1196,11 @@ static int ovl_get_lower_layers(struct ovl_fs *ofs, struct path *stack, } ofs->numlower++; } + + /* When all layers on same fs, overlay can use real inode numbers */ + if (!ofs->numlowerfs || (ofs->numlowerfs == 1 && !ofs->upper_mnt)) + ofs->xino_bits = 0; + err = 0; out: return err; @@ -1308,6 +1324,8 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent) sb->s_stack_depth = 0; sb->s_maxbytes = MAX_LFS_FILESIZE; + /* Assume underlaying fs uses 32bit inodes unless proven otherwise */ + ofs->xino_bits = BITS_PER_LONG - 32; if (ofs->config.upperdir) { if (!ofs->config.workdir) { pr_err("overlayfs: missing 'workdir'\n"); |