diff options
| -rw-r--r-- | tools/libxc/ia64/xc_ia64_linux_save.c | 38 | ||||
| -rw-r--r-- | tools/libxc/xc_domain_save.c | 41 | ||||
| -rw-r--r-- | tools/libxc/xenguest.h | 3 | ||||
| -rw-r--r-- | tools/xcutils/xc_save.c | 123 |
4 files changed, 48 insertions, 157 deletions
diff --git a/tools/libxc/ia64/xc_ia64_linux_save.c b/tools/libxc/ia64/xc_ia64_linux_save.c index 6c855eb4a6..db2d98cca0 100644 --- a/tools/libxc/ia64/xc_ia64_linux_save.c +++ b/tools/libxc/ia64/xc_ia64_linux_save.c @@ -382,8 +382,7 @@ out: int xc_domain_save(int xc_handle, int io_fd, uint32_t dom, uint32_t max_iters, uint32_t max_factor, uint32_t flags, int (*suspend)(void), - int hvm, void *(*init_qemu_maps)(int, unsigned), - void (*qemu_flip_buffer)(int, int)) + int hvm, void (*switch_qemu_logdirty)(int, unsigned)) { DECLARE_DOMCTL; xc_dominfo_t info; @@ -424,11 +423,6 @@ xc_domain_save(int xc_handle, int io_fd, uint32_t dom, uint32_t max_iters, char *mem; - /* HVM: shared-memory bitmaps for getting log-dirty bits from qemu-dm */ - unsigned long *qemu_bitmaps[2]; - int qemu_active = 0; - int qemu_non_active = 1; - /* for foreign p2m exposure */ unsigned long memmap_info_num_pages; /* Unsigned int was used before. To keep file format compatibility. */ @@ -545,14 +539,9 @@ xc_domain_save(int xc_handle, int io_fd, uint32_t dom, uint32_t max_iters, goto out; } - if (hvm) { - /* Get qemu-dm logging dirty pages too */ - void *seg = init_qemu_maps(dom, bitmap_size); - qemu_bitmaps[0] = seg; - qemu_bitmaps[1] = seg + bitmap_size; - qemu_active = 0; - qemu_non_active = 1; - } + /* Enable qemu-dm logging dirty pages to xen */ + if (hvm) + switch_qemu_logdirty(dom, 1); } else { /* This is a non-live suspend. Issue the call back to get the @@ -703,23 +692,6 @@ xc_domain_save(int xc_handle, int io_fd, uint32_t dom, uint32_t max_iters, goto out; } - if (hvm) { - unsigned int j; - /* Pull in the dirty bits from qemu-dm too */ - if (!last_iter) { - qemu_active = qemu_non_active; - qemu_non_active = qemu_active ? 0 : 1; - qemu_flip_buffer(dom, qemu_active); - for (j = 0; j < bitmap_size / sizeof(unsigned long); j++) { - to_send[j] |= qemu_bitmaps[qemu_non_active][j]; - qemu_bitmaps[qemu_non_active][j] = 0; - } - } else { - for (j = 0; j < bitmap_size / sizeof(unsigned long); j++) - to_send[j] |= qemu_bitmaps[qemu_active][j]; - } - } - sent_last_iter = sent_this_iter; //print_stats(xc_handle, dom, sent_this_iter, &stats, 1); @@ -762,6 +734,8 @@ xc_domain_save(int xc_handle, int io_fd, uint32_t dom, uint32_t max_iters, NULL, 0, NULL, 0, NULL ) < 0) { DPRINTF("Warning - couldn't disable shadow mode"); } + if ( hvm ) + switch_qemu_logdirty(dom, 0); } unlock_pages(to_send, bitmap_size); diff --git a/tools/libxc/xc_domain_save.c b/tools/libxc/xc_domain_save.c index 0c3a21e73b..8dfd3cdece 100644 --- a/tools/libxc/xc_domain_save.c +++ b/tools/libxc/xc_domain_save.c @@ -39,11 +39,6 @@ static unsigned long hvirt_start; /* #levels of page tables used by the current guest */ static unsigned int pt_levels; -/* HVM: shared-memory bitmaps for getting log-dirty bits from qemu-dm */ -static unsigned long *qemu_bitmaps[2]; -static int qemu_active; -static int qemu_non_active; - /* number of pfns this guest has (i.e. number of entries in the P2M) */ static unsigned long p2m_size; @@ -748,8 +743,7 @@ static xen_pfn_t *map_and_save_p2m_table(int xc_handle, int xc_domain_save(int xc_handle, int io_fd, uint32_t dom, uint32_t max_iters, uint32_t max_factor, uint32_t flags, int (*suspend)(void), - int hvm, void *(*init_qemu_maps)(int, unsigned), - void (*qemu_flip_buffer)(int, int)) + int hvm, void (*switch_qemu_logdirty)(int, unsigned)) { xc_dominfo_t info; DECLARE_DOMCTL; @@ -863,15 +857,9 @@ int xc_domain_save(int xc_handle, int io_fd, uint32_t dom, uint32_t max_iters, } } + /* Enable qemu-dm logging dirty pages to xen */ if ( hvm ) - { - /* Get qemu-dm logging dirty pages too */ - void *seg = init_qemu_maps(dom, BITMAP_SIZE); - qemu_bitmaps[0] = seg; - qemu_bitmaps[1] = seg + BITMAP_SIZE; - qemu_active = 0; - qemu_non_active = 1; - } + switch_qemu_logdirty(dom, 1); } else { @@ -1341,27 +1329,6 @@ int xc_domain_save(int xc_handle, int io_fd, uint32_t dom, uint32_t max_iters, goto out; } - if ( hvm ) - { - /* Pull in the dirty bits from qemu-dm too */ - if ( !last_iter ) - { - qemu_active = qemu_non_active; - qemu_non_active = qemu_active ? 0 : 1; - qemu_flip_buffer(dom, qemu_active); - for ( j = 0; j < BITMAP_SIZE / sizeof(unsigned long); j++ ) - { - to_send[j] |= qemu_bitmaps[qemu_non_active][j]; - qemu_bitmaps[qemu_non_active][j] = 0; - } - } - else - { - for ( j = 0; j < BITMAP_SIZE / sizeof(unsigned long); j++ ) - to_send[j] |= qemu_bitmaps[qemu_active][j]; - } - } - sent_last_iter = sent_this_iter; print_stats(xc_handle, dom, sent_this_iter, &stats, 1); @@ -1629,6 +1596,8 @@ int xc_domain_save(int xc_handle, int io_fd, uint32_t dom, uint32_t max_iters, XEN_DOMCTL_SHADOW_OP_OFF, NULL, 0, NULL, 0, NULL) < 0 ) DPRINTF("Warning - couldn't disable shadow mode"); + if ( hvm ) + switch_qemu_logdirty(dom, 0); } /* Flush last write and discard cache for file. */ diff --git a/tools/libxc/xenguest.h b/tools/libxc/xenguest.h index 03bc38cb6a..b7cf6beb84 100644 --- a/tools/libxc/xenguest.h +++ b/tools/libxc/xenguest.h @@ -26,8 +26,7 @@ int xc_domain_save(int xc_handle, int io_fd, uint32_t dom, uint32_t max_iters, uint32_t max_factor, uint32_t flags /* XCFLAGS_xxx */, int (*suspend)(void), int hvm, - void *(*init_qemu_maps)(int, unsigned), /* HVM only */ - void (*qemu_flip_buffer)(int, int)); /* HVM only */ + void (*switch_qemu_logdirty)(int, unsigned)); /* HVM only */ /** diff --git a/tools/xcutils/xc_save.c b/tools/xcutils/xc_save.c index f15674a183..15d42dacf5 100644 --- a/tools/xcutils/xc_save.c +++ b/tools/xcutils/xc_save.c @@ -101,115 +101,64 @@ static int suspend(void) * the new active buffer. xc_save can then process and clear the old * active buffer. */ -static char *qemu_active_path; -static char *qemu_next_active_path; -static int qemu_shmid = -1; -static struct xs_handle *xs; - -/* Mark the shared-memory segment for destruction */ -static void qemu_destroy_buffer(void) -{ - if (qemu_shmid != -1) - shmctl(qemu_shmid, IPC_RMID, NULL); - qemu_shmid = -1; -} - -/* Get qemu to change buffers. */ -static void qemu_flip_buffer(int domid, int next_active) +static void switch_qemu_logdirty(int domid, unsigned int enable) { - char digit = '0' + next_active; + struct xs_handle *xs; + char *path, *p, *ret_str, *cmd_str, **watch; unsigned int len; - char *active_str, **watch; struct timeval tv; fd_set fdset; - /* Tell qemu that we want it to start writing log-dirty bits to the - * other buffer */ - if (!xs_write(xs, XBT_NULL, qemu_next_active_path, &digit, 1)) - errx(1, "can't write next-active to store path (%s)\n", - qemu_next_active_path); - - /* Wait a while for qemu to signal that it has switched to the new - * active buffer */ - read_again: - tv.tv_sec = 5; - tv.tv_usec = 0; - FD_ZERO(&fdset); - FD_SET(xs_fileno(xs), &fdset); - if ((select(xs_fileno(xs) + 1, &fdset, NULL, NULL, &tv)) != 1) - errx(1, "timed out waiting for qemu to switch buffers\n"); - watch = xs_read_watch(xs, &len); - free(watch); - - active_str = xs_read(xs, XBT_NULL, qemu_active_path, &len); - if (active_str == NULL || active_str[0] - '0' != next_active) - /* Watch fired but value is not yet right */ - goto read_again; -} - -static void *init_qemu_maps(int domid, unsigned int bitmap_size) -{ - key_t key; - char key_ascii[17] = {0,}; - void *seg; - char *path, *p; - - /* Make a shared-memory segment */ - do { - key = rand(); /* No security, just a sequence of numbers */ - qemu_shmid = shmget(key, 2 * bitmap_size, - IPC_CREAT|IPC_EXCL|S_IRUSR|S_IWUSR); - if (qemu_shmid == -1 && errno != EEXIST) - errx(1, "can't get shmem to talk to qemu-dm"); - } while (qemu_shmid == -1); - - /* Remember to tidy up after ourselves */ - atexit(qemu_destroy_buffer); - - /* Map it into our address space */ - seg = shmat(qemu_shmid, NULL, 0); - if (seg == (void *) -1) - errx(1, "can't map shmem to talk to qemu-dm"); - memset(seg, 0, 2 * bitmap_size); - - /* Write the size of it into the first 32 bits */ - *(uint32_t *)seg = bitmap_size; - - /* Tell qemu about it */ if ((xs = xs_daemon_open()) == NULL) errx(1, "Couldn't contact xenstore"); if (!(path = strdup("/local/domain/0/device-model/"))) errx(1, "can't get domain path in store"); if (!(path = realloc(path, strlen(path) + 10 - + strlen("/logdirty/next-active") + 1))) + + strlen("/logdirty/cmd") + 1))) errx(1, "no memory for constructing xenstore path"); snprintf(path + strlen(path), 11, "%i", domid); strcat(path, "/logdirty/"); p = path + strlen(path); - strcpy(p, "key"); - snprintf(key_ascii, 17, "%16.16llx", (unsigned long long) key); - if (!xs_write(xs, XBT_NULL, path, key_ascii, 16)) - errx(1, "can't write key (%s) to store path (%s)\n", key_ascii, path); - /* Watch for qemu's indication of the active buffer, and request it - * to start writing to buffer 0 */ - strcpy(p, "active"); - if (!xs_watch(xs, path, "qemu-active-buffer")) + /* Watch for qemu's return value */ + strcpy(p, "ret"); + if (!xs_watch(xs, path, "qemu-logdirty-ret")) errx(1, "can't set watch in store (%s)\n", path); - if (!(qemu_active_path = strdup(path))) - errx(1, "no memory for copying xenstore path"); - strcpy(p, "next-active"); - if (!(qemu_next_active_path = strdup(path))) - errx(1, "no memory for copying xenstore path"); + if (!(cmd_str = strdup( enable == 0 ? "disable" : "enable"))) + errx(1, "can't get logdirty cmd path in store"); + + /* Tell qemu that we want it to start logging dirty page to Xen */ + strcpy(p, "cmd"); + if (!xs_write(xs, XBT_NULL, path, cmd_str, strlen(cmd_str))) + errx(1, "can't write to store path (%s)\n", + path); + + /* Wait a while for qemu to signal that it has service logdirty command */ + read_again: + tv.tv_sec = 5; + tv.tv_usec = 0; + FD_ZERO(&fdset); + FD_SET(xs_fileno(xs), &fdset); - qemu_flip_buffer(domid, 0); + if ((select(xs_fileno(xs) + 1, &fdset, NULL, NULL, &tv)) != 1) + errx(1, "timed out waiting for qemu logdirty response.\n"); + + watch = xs_read_watch(xs, &len); + free(watch); + + strcpy(p, "ret"); + ret_str = xs_read(xs, XBT_NULL, path, &len); + if (ret_str == NULL || strcmp(ret_str, cmd_str)) + /* Watch fired but value is not yet right */ + goto read_again; free(path); - return seg; + free(cmd_str); + free(ret_str); } int @@ -255,7 +204,7 @@ main(int argc, char **argv) } ret = xc_domain_save(si.xc_fd, io_fd, si.domid, maxit, max_f, si.flags, &suspend, !!(si.flags & XCFLAGS_HVM), - &init_qemu_maps, &qemu_flip_buffer); + &switch_qemu_logdirty); if (si.suspend_evtchn > 0) xc_suspend_evtchn_release(si.xce, si.suspend_evtchn); |