X-Git-Url: http://git.annexia.org/?p=libguestfs.git;a=blobdiff_plain;f=src%2Fguestfs.c;h=fdf5fede8b479f07e6fdefda8ca638360e2bb800;hp=0b3142c77523e24959c3090712f798d0ce3a17ac;hb=4507dd497f9a5eb8584e6d0937a87dc659cfa144;hpb=936108f54cbf8e81132a0a0a8c093a4056f0e11c diff --git a/src/guestfs.c b/src/guestfs.c index 0b3142c..fdf5fed 100644 --- a/src/guestfs.c +++ b/src/guestfs.c @@ -29,7 +29,9 @@ #include #include #include +#include #include + #include #include @@ -156,6 +158,7 @@ struct guestfs_h int autosync; const char *path; + const char *qemu; char *last_error; @@ -217,7 +220,9 @@ guestfs_create (void) str = getenv ("LIBGUESTFS_PATH"); g->path = str != NULL ? str : GUESTFS_DEFAULT_PATH; - /* XXX We should probably make QEMU configurable as well. */ + + str = getenv ("LIBGUESTFS_QEMU"); + g->qemu = str != NULL ? str : QEMU; g->main_loop = guestfs_get_default_main_loop (); @@ -511,6 +516,22 @@ guestfs_get_path (guestfs_h *g) return g->path; } +int +guestfs_set_qemu (guestfs_h *g, const char *qemu) +{ + if (qemu == NULL) + g->qemu = QEMU; + else + g->qemu = qemu; + return 0; +} + +const char * +guestfs_get_qemu (guestfs_h *g) +{ + return g->qemu; +} + /* Add a string to the current command line. */ static void incr_cmdline_size (guestfs_h *g) @@ -613,7 +634,7 @@ int guestfs_launch (guestfs_h *g) { static const char *dir_template = "/tmp/libguestfsXXXXXX"; - int r, i, len, pmore; + int r, i, len, pmore, memsize; int wfd[2], rfd[2]; int tries; const char *kernel_name = "vmlinuz." REPO "." host_cpu; @@ -622,6 +643,7 @@ guestfs_launch (guestfs_h *g) char *kernel = NULL, *initrd = NULL; char unixsock[256]; struct sockaddr_un addr; + struct stat statbuf; /* Configured? */ if (!g->cmdline) { @@ -681,6 +703,40 @@ guestfs_launch (guestfs_h *g) goto cleanup0; } + /* Choose a suitable memory size (in MB). This is more art + * than science, but you can help by doing + * ./configure --enable-debug-command + * and then running: + * debug sh free + * debug mem '' + * and seeing how much free memory is left for particular + * configurations. + * + * It's also helpful to report both the compressed and uncompressed + * size of the initramfs (ls -lh initramfs*.img; du -sh initramfs). + * + * XXX KVM virtio balloon driver? + */ + if (stat (initrd, &statbuf) != -1) { + /* Approximate size of the initramfs after it is decompressed + * in kernel memory. The compression factor is ~2.5-3. + */ + memsize = 3 * statbuf.st_size / 1024 / 1024; + + /* Approximate size used by the kernel. */ + memsize += 10; + + /* Want to give userspace some room, so: */ + memsize += 128; + +#if SIZEOF_LONG == 8 + /* On 64 bit, assume some overhead. */ + memsize += 64; +#endif + } else + memsize = 512; + + /* Make the temporary directory containing the socket. */ if (!g->tmpdir) { g->tmpdir = safe_strdup (g, dir_template); @@ -711,11 +767,12 @@ guestfs_launch (guestfs_h *g) if (r == 0) { /* Child (qemu). */ char vmchannel[256]; char append[256]; + char memsize_str[256]; /* Set up the full command line. Do this in the subprocess so we * don't need to worry about cleaning up. */ - g->cmdline[0] = (char *) QEMU; + g->cmdline[0] = (char *) g->qemu; /* Construct the -net channel parameter for qemu. */ snprintf (vmchannel, sizeof vmchannel, @@ -728,9 +785,11 @@ guestfs_launch (guestfs_h *g) VMCHANNEL_ADDR, VMCHANNEL_PORT, g->verbose ? " guestfs_verbose=1" : ""); + snprintf (memsize_str, sizeof memsize_str, "%d", memsize); + add_cmdline (g, "-m"); - add_cmdline (g, "384"); /* XXX Choose best size. */ -#if defined(__i386__) || defined(__x86_64) + add_cmdline (g, memsize_str); +#if 0 add_cmdline (g, "-no-kqemu"); /* Avoids a warning. */ #endif add_cmdline (g, "-kernel"); @@ -747,12 +806,12 @@ guestfs_launch (guestfs_h *g) add_cmdline (g, "-net"); add_cmdline (g, "user,vlan=0"); add_cmdline (g, "-net"); - add_cmdline (g, "nic,vlan=0"); + add_cmdline (g, "nic,model=rtl8139,vlan=0"); incr_cmdline_size (g); g->cmdline[g->cmdline_size-1] = NULL; if (g->verbose) { - fprintf (stderr, "%s", QEMU); + fprintf (stderr, "%s", g->qemu); for (i = 0; g->cmdline[i]; ++i) fprintf (stderr, " %s", g->cmdline[i]); fprintf (stderr, "\n"); @@ -775,8 +834,8 @@ guestfs_launch (guestfs_h *g) setpgid (0, 0); #endif - execv (QEMU, g->cmdline); /* Run qemu. */ - perror (QEMU); + execv (g->qemu, g->cmdline); /* Run qemu. */ + perror (g->qemu); _exit (1); } @@ -1433,7 +1492,6 @@ int guestfs__send_sync (guestfs_h *g, int proc_nr, xdrproc_t xdrp, char *args) { - char buffer[GUESTFS_MESSAGE_MAX]; struct guestfs_message_header hdr; XDR xdr; unsigned len; @@ -1446,6 +1504,23 @@ guestfs__send_sync (guestfs_h *g, int proc_nr, return -1; } + /* This is probably an internal error. Or perhaps we should just + * free the buffer anyway? + */ + if (g->msg_out != NULL) { + error (g, "guestfs__send_sync: msg_out should be NULL"); + return -1; + } + + /* We have to allocate this message buffer on the heap because + * it is quite large (although will be mostly unused). We + * can't allocate it on the stack because in some environments + * we have quite limited stack space available, notably when + * running in the JVM. + */ + g->msg_out = safe_malloc (g, GUESTFS_MESSAGE_MAX + 4); + xdrmem_create (&xdr, g->msg_out + 4, GUESTFS_MESSAGE_MAX, XDR_ENCODE); + /* Serialize the header. */ hdr.prog = GUESTFS_PROGRAM; hdr.vers = GUESTFS_PROTOCOL_VERSION; @@ -1454,10 +1529,9 @@ guestfs__send_sync (guestfs_h *g, int proc_nr, hdr.serial = serial; hdr.status = GUESTFS_STATUS_OK; - xdrmem_create (&xdr, buffer, sizeof buffer, XDR_ENCODE); if (!xdr_guestfs_message_header (&xdr, &hdr)) { error (g, "xdr_guestfs_message_header failed"); - return -1; + goto cleanup1; } /* Serialize the args. If any, because some message types @@ -1466,24 +1540,23 @@ guestfs__send_sync (guestfs_h *g, int proc_nr, if (xdrp) { if (!(*xdrp) (&xdr, args)) { error (g, "dispatch failed to marshal args"); - return -1; + goto cleanup1; } } + /* Get the actual length of the message, resize the buffer to match + * the actual length, and write the length word at the beginning. + */ len = xdr_getpos (&xdr); xdr_destroy (&xdr); - /* Allocate the outgoing message buffer. */ - g->msg_out = safe_malloc (g, len + 4); - + g->msg_out = safe_realloc (g, g->msg_out, len + 4); g->msg_out_size = len + 4; g->msg_out_pos = 0; xdrmem_create (&xdr, g->msg_out, 4, XDR_ENCODE); xdr_uint32_t (&xdr, &len); - memcpy (g->msg_out + 4, buffer, len); - if (guestfs__switch_to_sending (g) == -1) goto cleanup1;