From d62c16ff35a17743c2a0f8ebfb39f84064afcb3c Mon Sep 17 00:00:00 2001

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

Date: Thu, 3 Sep 2020 01:27:00 +0200

Subject: [PATCH 8/9] linux-user: Add support for btrfs ioctls used to manage

 quota

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This patch implements functionality for following ioctls:

BTRFS_IOC_QUOTA_CTL - Enabling/Disabling quota support

    Enable or disable quota support for a btrfs filesystem. Quota

    support is enabled or disabled using the ioctls third argument

    which represents a pointer to a following type:

    struct btrfs_ioctl_quota_ctl_args {

	__u64 cmd;

	__u64 status;

    };

    Before calling this ioctl, the 'cmd' field should be filled

    with one of the values 'BTRFS_QUOTA_CTL_ENABLE' (enabling quota)

    'BTRFS_QUOTA_CTL_DISABLE' (disabling quota).

BTRFS_IOC_QGROUP_CREATE - Creating/Removing a subvolume quota group

    Create or remove a subvolume quota group. The subvolume quota

    group is created or removed using the ioctl's third argument which

    represents a pointer to a following type:

    struct btrfs_ioctl_qgroup_create_args {

	__u64 create;

	__u64 qgroupid;

    };

    Before calling this ioctl, the 'create' field should be filled

    with the aproppriate value depending on if the user wants to

    create or remove a quota group (0 for removing, everything else

    for creating). Also, the 'qgroupid' field should be filled with

    the value for the quota group id that is to be created.

BTRFS_IOC_QGROUP_ASSIGN - Asigning or removing a quota group as child group

    Asign or remove a quota group as child quota group of another

    group in the btrfs filesystem. The asignment is done using the

    ioctl's third argument which represents a pointert to a following type:

    struct btrfs_ioctl_qgroup_assign_args {

	__u64 assign;

	__u64 src;

	__u64 dst;

    };

    Before calling this ioctl, the 'assign' field should be filled with

    the aproppriate value depending on if the user wants to asign or remove

    a quota group as a child quota group of another group (0 for removing,

    everythin else for asigning). Also, the 'src' and 'dst' fields should

    be filled with the aproppriate quota group id values depending on which

    quota group needs to asigned or removed as child quota group of another

    group ('src' gets asigned or removed as child group of 'dst').

BTRFS_IOC_QGROUP_LIMIT - Limiting the size of a quota group

    Limit the size of a quota group. The size of the quota group is limited

    with the ioctls third argument which represents a pointer to a following

    type:

    struct btrfs_ioctl_qgroup_limit_args {

	__u64	qgroupid;

	struct btrfs_qgroup_limit lim;

    };

    Before calling this ioctl, the 'qgroup' id field should be filled with

    aproppriate value of the quota group id for which the size is to be

    limited. The second field is of following type:

    struct btrfs_qgroup_limit {

	__u64	flags;

	__u64	max_rfer;

	__u64	max_excl;

	__u64	rsv_rfer;

	__u64	rsv_excl;

    };

    The 'max_rfer' field should be filled with the size to which the quota

    group should be limited. The 'flags' field can be used for passing

    additional options and can have values which can be found on:

    https://elixir.bootlin.com/linux/latest/source/include/uapi/linux/btrfs.h#L67

BTRFS_IOC_QUOTA_RESCAN_STATUS - Checking status of running rescan operation

    Check status of a running rescan operation. The status is checked using

    the ioctl's third argument which represents a pointer to a following type:

    struct btrfs_ioctl_quota_rescan_args {

        __u64   flags;

        __u64   progress;

        __u64   reserved[6];

    };

    If there is a rescan operation running, 'flags' field is set to 1, and

    'progress' field is set to aproppriate value which represents the progress

    of the operation.

BTRFS_IOC_QUOTA_RESCAN - Starting a rescan operation

    Start ar rescan operation to Trash all quota groups and scan the metadata

    again with the current config. Before calling this ioctl,

    BTRFS_IOC_QUOTA_RESCAN_STATUS sould be run to check if there is already a

    rescan operation runing. After that ioctl call, the received

    'struct btrfs_ioctl_quota_rescan_args' should be than passed as this ioctls

    third argument.

BTRFS_IOC_QUOTA_RESCAN_WAIT - Waiting for a rescan operation to finish

    Wait until a rescan operation is finished (if there is a rescan operation

    running). The third ioctls argument is ignored.

Implementation notes:

    Almost all of the ioctls in this patch use structure types as third arguments.

    That is the reason why aproppriate thunk definitions were 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: <20200823195014.116226-8-Filip.Bozuta@syrmia.com>

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

---

 linux-user/ioctls.h        | 27 +++++++++++++++++++++++++++

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

 linux-user/syscall_types.h | 29 +++++++++++++++++++++++++++++

 3 files changed, 63 insertions(+)

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

index 728880b9f3..882bfb3e88 100644

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

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

@@ -227,6 +227,33 @@

      IOCTL(BTRFS_IOC_LOGICAL_INO, IOC_RW,

            MK_PTR(MK_STRUCT(STRUCT_btrfs_ioctl_logical_ino_args)))

 #endif

+#ifdef BTRFS_IOC_QUOTA_CTL

+     IOCTL(BTRFS_IOC_QUOTA_CTL, IOC_RW,

+           MK_PTR(MK_STRUCT(STRUCT_btrfs_ioctl_quota_ctl_args)))

+#endif

+#ifdef BTRFS_IOC_QGROUP_ASSIGN

+     IOCTL(BTRFS_IOC_QGROUP_ASSIGN, IOC_W,

+           MK_PTR(MK_STRUCT(STRUCT_btrfs_ioctl_qgroup_assign_args)))

+#endif

+#ifdef BTRFS_IOC_QGROUP_CREATE

+     IOCTL(BTRFS_IOC_QGROUP_CREATE, IOC_W,

+           MK_PTR(MK_STRUCT(STRUCT_btrfs_ioctl_qgroup_create_args)))

+#endif

+#ifdef BTRFS_IOC_QGROUP_LIMIT

+     IOCTL(BTRFS_IOC_QGROUP_LIMIT, IOC_R,

+           MK_PTR(MK_STRUCT(STRUCT_btrfs_ioctl_qgroup_limit_args)))

+#endif

+#ifdef BTRFS_IOC_QUOTA_RESCAN

+     IOCTL(BTRFS_IOC_QUOTA_RESCAN, IOC_W,

+           MK_PTR(MK_STRUCT(STRUCT_btrfs_ioctl_quota_rescan_args)))

+#endif

+#ifdef BTRFS_IOC_QUOTA_RESCAN_STATUS

+     IOCTL(BTRFS_IOC_QUOTA_RESCAN_STATUS, IOC_R,

+           MK_PTR(MK_STRUCT(STRUCT_btrfs_ioctl_quota_rescan_args)))

+#endif

+#ifdef BTRFS_IOC_QUOTA_RESCAN_WAIT

+     IOCTL(BTRFS_IOC_QUOTA_RESCAN_WAIT, 0, TYPE_NULL)

+#endif

 #ifdef BTRFS_IOC_GET_DEV_STATS

      IOCTL(BTRFS_IOC_GET_DEV_STATS, IOC_RW,

            MK_PTR(MK_STRUCT(STRUCT_btrfs_ioctl_get_dev_stats)))

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

index 1d0bfb5479..10a7f91016 100644

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

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

@@ -985,6 +985,13 @@ struct target_rtc_pll_info {

 #define TARGET_BTRFS_IOC_DEV_INFO               TARGET_IOWRU(BTRFS_IOCTL_MAGIC, 30)

 #define TARGET_BTRFS_IOC_INO_PATHS              TARGET_IOWRU(BTRFS_IOCTL_MAGIC, 35)

 #define TARGET_BTRFS_IOC_LOGICAL_INO            TARGET_IOWRU(BTRFS_IOCTL_MAGIC, 36)

+#define TARGET_BTRFS_IOC_QUOTA_CTL              TARGET_IOWRU(BTRFS_IOCTL_MAGIC, 40)

+#define TARGET_BTRFS_IOC_QGROUP_ASSIGN          TARGET_IOWU(BTRFS_IOCTL_MAGIC, 41)

+#define TARGET_BTRFS_IOC_QGROUP_CREATE          TARGET_IOWU(BTRFS_IOCTL_MAGIC, 42)

+#define TARGET_BTRFS_IOC_QGROUP_LIMIT           TARGET_IORU(BTRFS_IOCTL_MAGIC, 43)

+#define TARGET_BTRFS_IOC_QUOTA_RESCAN           TARGET_IOWU(BTRFS_IOCTL_MAGIC, 44)

+#define TARGET_BTRFS_IOC_QUOTA_RESCAN_STATUS    TARGET_IORU(BTRFS_IOCTL_MAGIC, 45)

+#define TARGET_BTRFS_IOC_QUOTA_RESCAN_WAIT      TARGET_IO(BTRFS_IOCTL_MAGIC, 46)

 #define TARGET_BTRFS_IOC_GET_DEV_STATS          TARGET_IOWRU(BTRFS_IOCTL_MAGIC, 52)

 #define TARGET_BTRFS_IOC_GET_FEATURES           TARGET_IORU(BTRFS_IOCTL_MAGIC, 57)

 #define TARGET_BTRFS_IOC_SET_FEATURES           TARGET_IOWU(BTRFS_IOCTL_MAGIC, 57)

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

index 5566d101c2..d9b7106a69 100644

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

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

@@ -454,6 +454,35 @@ STRUCT(btrfs_ioctl_get_dev_stats,

                 128 - 2 - BTRFS_DEV_STAT_VALUES_MAX)) /* unused */

 #endif

+STRUCT(btrfs_ioctl_quota_ctl_args,

+       TYPE_ULONGLONG, /* cmd */

+       TYPE_ULONGLONG) /* status */

+

+STRUCT(btrfs_ioctl_quota_rescan_args,

+       TYPE_ULONGLONG, /* flags */

+       TYPE_ULONGLONG, /* progress */

+       MK_ARRAY(TYPE_ULONGLONG, 6)) /* reserved */

+

+STRUCT(btrfs_ioctl_qgroup_assign_args,

+       TYPE_ULONGLONG, /* assign */

+       TYPE_ULONGLONG, /* src */

+       TYPE_ULONGLONG) /* dst */

+

+STRUCT(btrfs_ioctl_qgroup_create_args,

+       TYPE_ULONGLONG, /* create */

+       TYPE_ULONGLONG) /* qgroupid */

+

+STRUCT(btrfs_qgroup_limit,

+       TYPE_ULONGLONG, /* flags */

+       TYPE_ULONGLONG, /* max_rfer */

+       TYPE_ULONGLONG, /* max_excl */

+       TYPE_ULONGLONG, /* rsv_rfer */

+       TYPE_ULONGLONG) /* rsv_excl */

+

+STRUCT(btrfs_ioctl_qgroup_limit_args,

+       TYPE_ULONGLONG, /* qgroupid */

+       MK_STRUCT(STRUCT_btrfs_qgroup_limit)) /* lim */

+

 STRUCT(btrfs_ioctl_feature_flags,

        TYPE_ULONGLONG, /* compat_flags */

        TYPE_ULONGLONG, /* compat_ro_flags */

-- 

2.26.2