[Qemu-devel] [PATCH 5/5] Adapt TPM host backend to use threadlets

[Andreas Niederl <andreas.niederl@iaik.tugraz.at>]

Signed-off-by: Andreas Niederl <andreas.niederl@iaik.tugraz.at>
---
 Makefile.objs         |    3 -
 hw/tpm_host_backend.c |  111 ++++++++++++++-----------------------------------
 2 files changed, 32 insertions(+), 82 deletions(-)

diff --git a/Makefile.objs b/Makefile.objs
index 55fd6b5..5209a9b 100644
--- a/Makefile.objs
+++ b/Makefile.objs
@@ -285,9 +285,6 @@ hw-obj-$(CONFIG_VIRTFS) += virtio-9p-xattr-user.o virtio-9p-posix-acl.o
 
 # TPM passthrough device
 hw-obj-$(CONFIG_TPM) += tpm_tis.o tpm_backend.o tpm_host_backend.o
-ifndef CONFIG_THREAD
-common-obj-$(CONFIG_TPM) += qemu-thread.o
-endif
 
 ######################################################################
 # libdis
diff --git a/hw/tpm_host_backend.c b/hw/tpm_host_backend.c
index 4ae9deb..9204ede 100644
--- a/hw/tpm_host_backend.c
+++ b/hw/tpm_host_backend.c
@@ -20,17 +20,11 @@
 #include <signal.h>
 
 #include "qemu-common.h"
-#include "qemu-thread.h"
+#include "qemu-threadlet.h"
 
 #include "hw/tpm_int.h"
 
 
-typedef struct {
-    QemuThread id;
-    QemuMutex  lock;
-    QemuCond   send_command;
-} TPMThread;
-
 #define STATUS_DONE        (1 << 1)
 #define STATUS_IN_PROGRESS (1 << 0)
 #define STATUS_IDLE         0
@@ -38,7 +32,7 @@ typedef struct {
 typedef struct {
     TPMDriver common;
 
-    TPMThread thread;
+    ThreadletWork work;
 
     uint8_t   send_status;
     uint8_t   recv_status;
@@ -56,7 +50,6 @@ static int tpm_host_send(TPMDriver *drv, uint8_t locty, uint32_t len)
 
     drv->locty = locty;
 
-    qemu_mutex_lock(&hdrv->thread.lock);
     switch (hdrv->send_status) {
         case STATUS_IN_PROGRESS:
             break;
@@ -65,7 +58,7 @@ static int tpm_host_send(TPMDriver *drv, uint8_t locty, uint32_t len)
             hdrv->recv_len = TPM_MAX_PKT;
             /* asynchronous send */
             n = 1;
-            qemu_cond_signal( &hdrv->thread.send_command);
+            submit_work(&hdrv->work);
             break;
         case STATUS_DONE:
             n = hdrv->send_len;
@@ -78,7 +71,6 @@ static int tpm_host_send(TPMDriver *drv, uint8_t locty, uint32_t len)
                     hdrv->send_status);
             break;
     }
-    qemu_mutex_unlock(&hdrv->thread.lock);
 
     return n;
 }
@@ -90,7 +82,6 @@ static int tpm_host_recv(TPMDriver *drv, uint8_t locty, uint32_t len)
 
     drv->locty = locty;
 
-    qemu_mutex_lock(&hdrv->thread.lock);
     switch (hdrv->recv_status) {
         case STATUS_IN_PROGRESS:
             break;
@@ -107,7 +98,6 @@ static int tpm_host_recv(TPMDriver *drv, uint8_t locty, uint32_t len)
                     hdrv->recv_status);
             break;
     }
-    qemu_mutex_unlock(&hdrv->thread.lock);
 
     return n;
 }
@@ -153,82 +143,50 @@ static int unix_read(int fd, uint8_t *buf, uint32_t len)
     return len - len1;
 }
 
-static void die2(int err, const char *what)
-{
-    fprintf(stderr, "%s failed: %s\n", what, strerror(err));
-    abort();
-}
-
-static void die(const char *what)
+static void tpm_host_send_receive(ThreadletWork *work)
 {
-    die2(errno, what);
-}
-
-static void *tpm_host_thread(void *opaque)
-{
-    TPMHostDriver *drv = opaque;
+    TPMHostDriver *drv = container_of(work, TPMHostDriver, work);
     TPMDriver     *s   = &drv->common;
-    sigset_t  set;
     uint32_t  tpm_ret;
     int ret;
 
-    /* block all signals */
-    if (sigfillset(&set)) {
-        die("sigfillset");
-    }
-    if (sigprocmask(SIG_BLOCK, &set, NULL)) {
-        die("sigprocmask");
-    }
-
-    qemu_mutex_lock(&drv->thread.lock);
-    while (1) {
-        qemu_cond_wait(&drv->thread.send_command, &drv->thread.lock);
-        drv->send_status = STATUS_IN_PROGRESS;
-        qemu_mutex_unlock(&drv->thread.lock);
+    drv->send_status = STATUS_IN_PROGRESS;
 
-        DSHOW_BUFF(s->buf, "To TPM");
+    DSHOW_BUFF(s->buf, "To TPM");
 
-        ret = unix_write(drv->fd, s->buf, drv->send_len);
+    ret = unix_write(drv->fd, s->buf, drv->send_len);
 
-        qemu_mutex_lock(&drv->thread.lock);
-        drv->send_len    = ret;
-        drv->send_status = STATUS_DONE;
+    drv->send_len    = ret;
+    drv->send_status = STATUS_DONE;
 
-        if (ret < 0) {
-            fprintf(stderr, "Error: while transmitting data to host tpm"
-                    ": %s (%i)\n",
-                    strerror(errno), errno);
-            continue;
-        }
+    if (ret < 0) {
+      fprintf(stderr, "Error: while transmitting data to host tpm"
+          ": %s (%i)\n",
+          strerror(errno), errno);
+    }
 
-        drv->recv_status = STATUS_IN_PROGRESS;
-        qemu_mutex_unlock(&drv->thread.lock);
+    drv->recv_status = STATUS_IN_PROGRESS;
 
-        ret = unix_read(drv->fd, s->buf, drv->recv_len);
+    ret = unix_read(drv->fd, s->buf, drv->recv_len);
 
-        qemu_mutex_lock(&drv->thread.lock);
-        drv->recv_len    = ret;
-        drv->recv_status = STATUS_DONE;
-        drv->send_status = STATUS_IDLE;
+    drv->recv_len    = ret;
+    drv->recv_status = STATUS_DONE;
+    drv->send_status = STATUS_IDLE;
 
-        if (ret < 0) {
-            fprintf(stderr, "Error: while reading data from host tpm"
-                    ": %s (%i)\n",
-                    strerror(errno), errno);
-            continue;
-        }
+    if (ret < 0) {
+      fprintf(stderr, "Error: while reading data from host tpm"
+          ": %s (%i)\n",
+          strerror(errno), errno);
+    }
 
-        DSHOW_BUFF(s->buf, "From TPM");
+    DSHOW_BUFF(s->buf, "From TPM");
 
-        tpm_ret = (s->buf[8])*256 + s->buf[9];
-        if (tpm_ret) {
-            DPRINTF("tpm command failed with error %d\n", tpm_ret);
-        } else {
-            DPRINTF("tpm command succeeded\n");
-        }
+    tpm_ret = (s->buf[8])*256 + s->buf[9];
+    if (tpm_ret) {
+      DPRINTF("tpm command failed with error %d\n", tpm_ret);
+    } else {
+      DPRINTF("tpm command succeeded\n");
     }
-
-    return NULL;
 }
 
 
@@ -236,7 +194,6 @@ TPMDriver *qemu_tpm_host_open(QemuOpts *opts)
 {
     TPMDriver      *drv = NULL;
     TPMHostDriver *hdrv = NULL;
-    TPMThread *thread = NULL;
     char *path = NULL;
     int fd = -1;
 
@@ -263,11 +220,7 @@ TPMDriver *qemu_tpm_host_open(QemuOpts *opts)
     }
     hdrv->fd = fd;
 
-    thread = &hdrv->thread;
-    qemu_mutex_init(&thread->lock);
-    qemu_cond_init( &thread->send_command);
-
-    qemu_thread_create(&thread->id, &tpm_host_thread, hdrv);
+    hdrv->work.func = tpm_host_send_receive;
 
     return drv;
 
-- 
1.7.4.1