[PATCH v7 12/16] vboxsf: Implement fileattr_get for case sensitivity
STALE256d
From: Chuck Lever <cel@kernel.org>
Date: 2026-01-22 16:03:46
Also in:
linux-api, linux-cifs, linux-f2fs-devel, linux-fsdevel, linux-nfs, linux-xfs
Subsystem:
filesystems (vfs and infrastructure), the rest, virtual box shared folder vfs driver · Maintainers:
Alexander Viro, Christian Brauner, Linus Torvalds, Jori Koolstra
Revision v7 of 5 in this series.
Revisions (5)
From: Chuck Lever <redacted> Upper layers such as NFSD need a way to query whether a filesystem handles filenames in a case-sensitive manner. Report VirtualBox shared folder case handling behavior via the FS_XFLAG_CASEFOLD flag. The case sensitivity property is queried from the VirtualBox host service at mount time and cached in struct vboxsf_sbi. The host determines case sensitivity based on the underlying host filesystem (for example, Windows NTFS is case-insensitive while Linux ext4 is case-sensitive). VirtualBox shared folders always preserve filename case exactly as provided by the guest. The host interface does not expose a case_preserving property, so this is hardcoded to true. The callback is registered in all three inode_operations structures (directory, file, and symlink) to ensure consistent reporting across all inode types. Signed-off-by: Chuck Lever <redacted> --- fs/vboxsf/dir.c | 1 + fs/vboxsf/file.c | 6 ++++-- fs/vboxsf/super.c | 4 ++++ fs/vboxsf/utils.c | 31 +++++++++++++++++++++++++++++++ fs/vboxsf/vfsmod.h | 6 ++++++ 5 files changed, 46 insertions(+), 2 deletions(-)
diff --git a/fs/vboxsf/dir.c b/fs/vboxsf/dir.c
index 42bedc4ec7af..c5bd3271aa96 100644
--- a/fs/vboxsf/dir.c
+++ b/fs/vboxsf/dir.c@@ -477,4 +477,5 @@ const struct inode_operations vboxsf_dir_iops = { .symlink = vboxsf_dir_symlink, .getattr = vboxsf_getattr, .setattr = vboxsf_setattr, + .fileattr_get = vboxsf_fileattr_get, };
diff --git a/fs/vboxsf/file.c b/fs/vboxsf/file.c
index 4bebd947314a..06308e38a70d 100644
--- a/fs/vboxsf/file.c
+++ b/fs/vboxsf/file.c@@ -223,7 +223,8 @@ const struct file_operations vboxsf_reg_fops = { const struct inode_operations vboxsf_reg_iops = { .getattr = vboxsf_getattr, - .setattr = vboxsf_setattr + .setattr = vboxsf_setattr, + .fileattr_get = vboxsf_fileattr_get, }; static int vboxsf_read_folio(struct file *file, struct folio *folio)
@@ -390,5 +391,6 @@ static const char *vboxsf_get_link(struct dentry *dentry, struct inode *inode, } const struct inode_operations vboxsf_lnk_iops = { - .get_link = vboxsf_get_link + .get_link = vboxsf_get_link, + .fileattr_get = vboxsf_fileattr_get, };
diff --git a/fs/vboxsf/super.c b/fs/vboxsf/super.c
index 241647b060ee..fcabeca2a339 100644
--- a/fs/vboxsf/super.c
+++ b/fs/vboxsf/super.c@@ -185,6 +185,10 @@ static int vboxsf_fill_super(struct super_block *sb, struct fs_context *fc) if (err) goto fail_unmap; + err = vboxsf_query_case_sensitive(sbi); + if (err) + goto fail_unmap; + sb->s_magic = VBOXSF_SUPER_MAGIC; sb->s_blocksize = 1024; sb->s_maxbytes = MAX_LFS_FILESIZE;
diff --git a/fs/vboxsf/utils.c b/fs/vboxsf/utils.c
index 9515bbf0b54c..658b8b0ebbd7 100644
--- a/fs/vboxsf/utils.c
+++ b/fs/vboxsf/utils.c@@ -11,6 +11,7 @@ #include <linux/sizes.h> #include <linux/pagemap.h> #include <linux/vfs.h> +#include <linux/fileattr.h> #include "vfsmod.h" struct inode *vboxsf_new_inode(struct super_block *sb)
@@ -567,3 +568,33 @@ int vboxsf_dir_read_all(struct vboxsf_sbi *sbi, struct vboxsf_dir_info *sf_d, return err; } + +int vboxsf_query_case_sensitive(struct vboxsf_sbi *sbi) +{ + struct shfl_volinfo volinfo = {}; + u32 buf_len; + int err; + + buf_len = sizeof(volinfo); + err = vboxsf_fsinfo(sbi->root, 0, SHFL_INFO_GET | SHFL_INFO_VOLUME, + &buf_len, &volinfo); + if (err) + return err; + + sbi->case_insensitive = !volinfo.properties.case_sensitive; + return 0; +} + +int vboxsf_fileattr_get(struct dentry *dentry, struct file_kattr *fa) +{ + struct vboxsf_sbi *sbi = VBOXSF_SBI(dentry->d_sb); + + /* + * VirtualBox shared folders preserve filename case exactly as + * provided by the guest (the default). The host interface does + * not expose a case-preservation property. + */ + if (sbi->case_insensitive) + fa->fsx_xflags |= FS_XFLAG_CASEFOLD; + return 0; +}
diff --git a/fs/vboxsf/vfsmod.h b/fs/vboxsf/vfsmod.h
index 05973eb89d52..b61afd0ce842 100644
--- a/fs/vboxsf/vfsmod.h
+++ b/fs/vboxsf/vfsmod.h@@ -47,6 +47,7 @@ struct vboxsf_sbi { u32 next_generation; u32 root; int bdi_id; + bool case_insensitive; }; /* per-inode information */
@@ -111,6 +112,11 @@ void vboxsf_dir_info_free(struct vboxsf_dir_info *p); int vboxsf_dir_read_all(struct vboxsf_sbi *sbi, struct vboxsf_dir_info *sf_d, u64 handle); +int vboxsf_query_case_sensitive(struct vboxsf_sbi *sbi); + +struct file_kattr; +int vboxsf_fileattr_get(struct dentry *dentry, struct file_kattr *fa); + /* from vboxsf_wrappers.c */ int vboxsf_connect(void); void vboxsf_disconnect(void);
--
2.52.0