From 58252f756d7fb2a8516c0815034c0bded4697852 Mon Sep 17 00:00:00 2001

From: Filip Bozuta <Filip.Bozuta@syrmia.com>

Date: Thu, 3 Sep 2020 01:26:59 +0200

Subject: [PATCH 7/9] linux-user: Add support for two btrfs ioctls used for

 subvolume

MIME-Version: 1.0

Content-Type: text/plain; charset=UTF-8

Content-Transfer-Encoding: 8bit

This patch implements functionality for following ioctl:

BTRFS_IOC_DEFAULT_SUBVOL - Setting a default subvolume

    Set a default subvolume for a btrfs filesystem. The third

    ioctl's argument is a '__u64' (unsigned long long) which

    represents the id of a subvolume that is to be set as

    the default.

BTRFS_IOC_GET_SUBVOL_ROOTREF - Getting tree and directory id of subvolumes

    Read tree and directory id of subvolumes from a btrfs

    filesystem. The tree and directory id's are returned in the

    ioctl's third argument which represents a pointer to a

    following type:

    struct btrfs_ioctl_get_subvol_rootref_args {

		/* in/out, minimum id of rootref's treeid to be searched */

		__u64 min_treeid;

		/* out */

		struct {

			__u64 treeid;

			__u64 dirid;

		} rootref[BTRFS_MAX_ROOTREF_BUFFER_NUM];

		/* out, number of found items */

		__u8 num_items;

		__u8 align[7];

     };

     Before calling this ioctl, 'min_treeid' field should be filled

     with value that represent the minimum value for the tree id.

Implementation notes:

    Ioctl BTRFS_IOC_GET_SUBVOL_ROOTREF uses the above mentioned structure

    type as third argument. That is the reason why a aproppriate thunk

    structure definition is added in file 'syscall_types.h'.

Signed-off-by: Filip Bozuta <Filip.Bozuta@syrmia.com>

Tested-by: Daniel P. Berrangé <berrange@redhat.com>

Message-Id: <20200823195014.116226-7-Filip.Bozuta@syrmia.com>

Signed-off-by: Laurent Vivier <laurent@vivier.eu>

---

 linux-user/ioctls.h        |  7 +++++++

 linux-user/syscall_defs.h  |  3 +++

 linux-user/syscall_types.h | 13 +++++++++++++

 3 files changed, 23 insertions(+)

diff --git a/linux-user/ioctls.h b/linux-user/ioctls.h

index 169f98f7a3..728880b9f3 100644

--- a/linux-user/ioctls.h

+++ b/linux-user/ioctls.h

@@ -206,6 +206,9 @@

      IOCTL(BTRFS_IOC_INO_LOOKUP, IOC_RW,

            MK_PTR(MK_STRUCT(STRUCT_btrfs_ioctl_ino_lookup_args)))

 #endif

+#ifdef BTRFS_IOC_DEFAULT_SUBVOL

+     IOCTL(BTRFS_IOC_DEFAULT_SUBVOL, IOC_W, MK_PTR(TYPE_ULONGLONG))

+#endif

 #ifdef BTRFS_IOC_SUBVOL_GETFLAGS

      IOCTL(BTRFS_IOC_SUBVOL_GETFLAGS, IOC_R, MK_PTR(TYPE_ULONGLONG))

 #endif

@@ -248,6 +251,10 @@

      IOCTL(BTRFS_IOC_GET_SUBVOL_INFO, IOC_R,

            MK_PTR(MK_STRUCT(STRUCT_btrfs_ioctl_get_subvol_info_args)))

 #endif

+#ifdef BTRFS_IOC_GET_SUBVOL_ROOTREF

+     IOCTL(BTRFS_IOC_GET_SUBVOL_ROOTREF, IOC_RW,

+           MK_PTR(MK_STRUCT(STRUCT_btrfs_ioctl_get_subvol_rootref_args)))

+#endif

 #ifdef BTRFS_IOC_INO_LOOKUP_USER

      IOCTL(BTRFS_IOC_INO_LOOKUP_USER, IOC_RW,

            MK_PTR(MK_STRUCT(STRUCT_btrfs_ioctl_ino_lookup_user_args)))

diff --git a/linux-user/syscall_defs.h b/linux-user/syscall_defs.h

index a6a9454b85..1d0bfb5479 100644

--- a/linux-user/syscall_defs.h

+++ b/linux-user/syscall_defs.h

@@ -976,6 +976,8 @@ struct target_rtc_pll_info {

 #define TARGET_BTRFS_IOC_SUBVOL_CREATE          TARGET_IOWU(BTRFS_IOCTL_MAGIC, 14)

 #define TARGET_BTRFS_IOC_SNAP_DESTROY           TARGET_IOWU(BTRFS_IOCTL_MAGIC, 15)

 #define TARGET_BTRFS_IOC_INO_LOOKUP             TARGET_IOWRU(BTRFS_IOCTL_MAGIC, 18)

+#define TARGET_BTRFS_IOC_DEFAULT_SUBVOL         TARGET_IOW(BTRFS_IOCTL_MAGIC, 19,\

+                                                           abi_ullong)

 #define TARGET_BTRFS_IOC_SUBVOL_GETFLAGS        TARGET_IOR(BTRFS_IOCTL_MAGIC, 25,\

                                                            abi_ullong)

 #define TARGET_BTRFS_IOC_SUBVOL_SETFLAGS        TARGET_IOW(BTRFS_IOCTL_MAGIC, 26,\

@@ -989,6 +991,7 @@ struct target_rtc_pll_info {

 #define TARGET_BTRFS_IOC_GET_SUPPORTED_FEATURES TARGET_IORU(BTRFS_IOCTL_MAGIC, 57)

 #define TARGET_BTRFS_IOC_LOGICAL_INO_V2         TARGET_IOWRU(BTRFS_IOCTL_MAGIC, 59)

 #define TARGET_BTRFS_IOC_GET_SUBVOL_INFO        TARGET_IORU(BTRFS_IOCTL_MAGIC, 60)

+#define TARGET_BTRFS_IOC_GET_SUBVOL_ROOTREF     TARGET_IOWRU(BTRFS_IOCTL_MAGIC, 61)

 #define TARGET_BTRFS_IOC_INO_LOOKUP_USER        TARGET_IOWRU(BTRFS_IOCTL_MAGIC, 62)

 /* usb ioctls */

diff --git a/linux-user/syscall_types.h b/linux-user/syscall_types.h

index b84e14235f..5566d101c2 100644

--- a/linux-user/syscall_types.h

+++ b/linux-user/syscall_types.h

@@ -431,6 +431,19 @@ STRUCT(btrfs_ioctl_dev_info_args,

        MK_ARRAY(TYPE_CHAR, BTRFS_DEVICE_PATH_NAME_MAX)) /* path */

 #endif

+#ifdef BTRFS_IOC_GET_SUBVOL_ROOTREF

+STRUCT(rootref,

+       TYPE_ULONGLONG, /* treeid */

+       TYPE_ULONGLONG) /* dirid */

+

+STRUCT(btrfs_ioctl_get_subvol_rootref_args,

+       TYPE_ULONGLONG, /* min_treeid */

+       MK_ARRAY(MK_STRUCT(STRUCT_rootref),

+                BTRFS_MAX_ROOTREF_BUFFER_NUM), /* rootref */

+       TYPE_CHAR, /* num_items */

+       MK_ARRAY(TYPE_CHAR, 7)) /* align */

+#endif

+

 #ifdef BTRFS_IOC_GET_DEV_STATS

 STRUCT(btrfs_ioctl_get_dev_stats,

        TYPE_ULONGLONG, /* devid */

-- 

2.26.2