thin-provisioning-tools/functional-tests/device-mapper/ioctl.scm
2017-10-06 15:26:10 +01:00

211 lines
6.3 KiB
Scheme

(library
(device-mapper ioctl)
(export dm-open
dm-close
with-dm
get-version
remove-all
list-devices
create-device)
(import (chezscheme)
(fmt fmt)
(srfi s8 receive)
(utils))
(define __ (load-shared-object "./device-mapper/dm-ioctl.so"))
(define (fail msg)
(raise
(condition
(make-error)
(make-message-condition msg))))
(define-ftype DMIoctlInterface
(struct
(fd int)))
(define open% (foreign-procedure "dm_open" () (* DMIoctlInterface)))
(define (dm-open)
(let ((ptr (open%)))
(if (ftype-pointer-null? ptr)
(fail "couldn't open ioctl interface (permissions?)")
ptr)))
(define dm-close
(foreign-procedure "dm_close" ((* DMIoctlInterface)) void))
(define-syntax with-dm
(syntax-rules ()
((_ (name) b1 b2 ...)
(let ((name (dm-open)))
(dynamic-wind
(lambda () #f)
(lambda () b1 b2 ...)
(lambda () (dm-close name)))))))
(define-record-type dm-version (fields major minor patch))
(define (get-version dm)
(define get
(foreign-procedure "dm_version" ((* DMIoctlInterface)
(* unsigned-32)
(* unsigned-32)
(* unsigned-32)) int))
(define (alloc-u32)
(make-ftype-pointer unsigned-32
(foreign-alloc (ftype-sizeof unsigned-32))))
(define (deref-u32 p)
(ftype-ref unsigned-32 () p))
(let ((major (alloc-u32))
(minor (alloc-u32))
(patch (alloc-u32)))
(if (zero? (get dm major minor patch))
(let ((r (make-dm-version (deref-u32 major)
(deref-u32 minor)
(deref-u32 patch))))
(foreign-free (ftype-pointer-address major))
(foreign-free (ftype-pointer-address minor))
(foreign-free (ftype-pointer-address patch))
r)
(fail "couldn't get dm version"))))
(define (remove-all dm)
(define do-it
(foreign-procedure "dm_remove_all" ((* DMIoctlInterface)) int))
(let ((r (do-it dm)))
(unless (zero? r)
(fail "remove-all failed"))))
(define-ftype DevList
(struct
(next (* DevList))
(major unsigned)
(minor unsigned)
(name (* unsigned-8))))
(define-ftype DevListPtr (* DevList))
(define-record-type device-details
(fields name major minor))
(define (cstring->string str)
(let loop ((i 0)
(acc '()))
(let ((c (ftype-ref unsigned-8 () str i)))
(if (zero? c)
(list->string (reverse acc))
(loop (+ i 1) (cons (integer->char c) acc))))))
(define (string->cstring str)
(let* ((len (string-length str))
(cstr (make-ftype-pointer unsigned-8
(foreign-alloc (+ 1 len)))))
(let loop ((i 0))
(if (= i len)
(begin
(ftype-set! unsigned-8 () cstr i 0)
cstr)
(ftype-set! unsigned-8 () cstr i (string-ref str i))))))
;;; FIXME: put a dynamic wind in to ensure the dev list gets freed
(define (list-devices dm)
(define list-devs
(foreign-procedure "dm_list_devices" ((* DMIoctlInterface) (* DevListPtr)) int))
(let ((pp (make-ftype-pointer DevListPtr
(foreign-alloc (ftype-sizeof DevListPtr)))))
(if (zero? (list-devs dm pp))
(let loop ((dl (ftype-ref DevListPtr () pp))
(acc '()))
;(fmt #t "dl: " dl ", acc: " acc)
(if (ftype-pointer-null? dl)
acc
(loop (ftype-ref DevList (next) dl)
(cons (make-device-details
(cstring->string (ftype-ref DevList (name) dl))
(ftype-ref DevList (major) dl)
(ftype-ref DevList (minor) dl))
acc))))
(fail "dm_list_devices ioctl failed"))))
(define (create-device dm name uuid)
(define create
(foreign-procedure "dm_create_device" ((* DMIoctlInterface) string string) int))
(unless (zero? (create dm name uuid))
(fail "create-device failed")))
(define-syntax define-dev-cmd
(syntax-rules ()
((_ nm proc)
(define (nm dm name)
(define fn
(foreign-procedure proc ((* DMIoctlInterface) string) int))
(unless (zero? (fn dm name))
(fail (string-append proc " failed")))))))
(define-dev-cmd remove-device "dm_remove_device")
(define-dev-cmd suspend-device "dm_suspend_device")
(define-dev-cmd resume-device "dm_resume_device")
(define-dev-cmd clear-device "dm_clear_device")
(define-ftype Target
(struct
(next (* Target))
(len unsigned-64)
(type (* unsigned-8))
(args (* unsigned-8))))
(define-ftype TargetPtr (* Target))
(define-record-type target
(fields (mutable len) (mutable type) (mutable args)))
(define (build-c-target next len type args)
(let ((t (make-ftype-pointer Target
(foreign-alloc
(ftype-sizeof Target)))))
(ftype-set! Target (next) t next)
(ftype-set! Target (len) t len)
(ftype-set! Target (type) t (string->cstring type))
(ftype-set! Target (args) t (string->cstring args))))
(define (build-c-targets targets)
(let loop ((t targets)
(tail (make-ftype-pointer Target 0)))
(if (null? t)
tail
(loop (cdr targets)
(build-c-target tail (target-len t) (target-type t) (target-args t))))))
(define (free-c-targets t)
(let loop ((t t)
(acc '()))
(if (ftype-pointer-null? t)
(map foreign-free acc)
(loop (ftype-ref Target (next) t) (cons t acc)))))
;; targets should be dlambdas with 'size, 'type and 'format methods
(define (load-table dm name targets)
(define load
(foreign-procedure "dm_load" ((* DMIoctlInterface) string (* Target)) int))
(define (dlambda->target t)
(make-target (t 'size) (t 'type) (t 'format)))
(let* ((ctargets (build-c-targets (map dlambda->target targets)))
(r (load dm name ctargets)))
(free-c-targets ctargets)
(unless (zero? r)
(fail "dm_load failed"))))
)