path: root/fs
diff options
authorAmir Goldstein <amir73il@gmail.com>2020-02-21 16:34:42 +0200
committerMiklos Szeredi <mszeredi@redhat.com>2020-03-13 15:53:06 +0100
commit53afcd310e867d25e394718558783c476301205c (patch)
tree2d3d1f420d360e1c0aacbee9d9c6c93951145849 /fs
parentovl: fix lock in ovl_llseek() (diff)
ovl: fix some xino configurations
Fix up two bugs in the coversion to xino_mode: 1. xino=off does not always end up in disabled mode 2. xino=auto on 32bit arch should end up in disabled mode Take a proactive approach to disabling xino on 32bit kernel: 1. Disable XINO_AUTO config during build time 2. Disable xino with a warning on mount time As a by product, xino=on on 32bit arch also ends up in disabled mode. We never intended to enable xino on 32bit arch and this will make the rest of the logic simpler. Fixes: 0f831ec85eda ("ovl: simplify ovl_same_sb() helper") Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Diffstat (limited to 'fs')
2 files changed, 9 insertions, 1 deletions
diff --git a/fs/overlayfs/Kconfig b/fs/overlayfs/Kconfig
index 444e2da4f60e..714c14c47ca5 100644
--- a/fs/overlayfs/Kconfig
+++ b/fs/overlayfs/Kconfig
@@ -93,6 +93,7 @@ config OVERLAY_FS_XINO_AUTO
bool "Overlayfs: auto enable inode number mapping"
default n
depends on OVERLAY_FS
+ depends on 64BIT
If this config option is enabled then overlay filesystems will use
unused high bits in undelying filesystem inode numbers to map all
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index 319fe0d355b0..ac967f1cb6e5 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -1411,6 +1411,8 @@ static int ovl_get_layers(struct super_block *sb, struct ovl_fs *ofs,
if (ofs->config.xino == OVL_XINO_ON)
pr_info("\"xino=on\" is useless with all layers on same fs, ignore.\n");
ofs->xino_mode = 0;
+ } else if (ofs->config.xino == OVL_XINO_OFF) {
+ ofs->xino_mode = -1;
} else if (ofs->config.xino == OVL_XINO_ON && ofs->xino_mode < 0) {
* This is a roundup of number of bits needed for encoding
@@ -1623,8 +1625,13 @@ 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 */
- if (ofs->config.xino != OVL_XINO_OFF)
+ if (ofs->config.xino != OVL_XINO_OFF) {
ofs->xino_mode = BITS_PER_LONG - 32;
+ if (!ofs->xino_mode) {
+ pr_warn("xino not supported on 32bit kernel, falling back to xino=off.\n");
+ ofs->config.xino = OVL_XINO_OFF;
+ }
+ }
/* alloc/destroy_inode needed for setting up traps in inode cache */
sb->s_op = &ovl_super_operations;