X-Git-Url: http://git.annexia.org/?a=blobdiff_plain;f=src%2Fguestfs.c;h=e30804464f661bf30f5778e26baf3d0d7d566cb9;hb=1bf76681103c755b1a650e002292aa33f7d0babf;hp=4c94c325238d80783ccdc1f8bc869361a0023f9d;hpb=ade327a7af869d4d70e28e2a596473943e0299dd;p=libguestfs.git diff --git a/src/guestfs.c b/src/guestfs.c index 4c94c32..e308044 100644 --- a/src/guestfs.c +++ b/src/guestfs.c @@ -1,5 +1,5 @@ /* libguestfs - * Copyright (C) 2009 Red Hat Inc. + * Copyright (C) 2009-2010 Red Hat Inc. * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public @@ -60,12 +60,14 @@ #include #include +#include "c-ctype.h" +#include "glthread/lock.h" +#include "ignore-value.h" + #include "guestfs.h" #include "guestfs-internal.h" #include "guestfs-internal-actions.h" #include "guestfs_protocol.h" -#include "c-ctype.h" -#include "ignore-value.h" #ifdef HAVE_GETTEXT #include "gettext.h" @@ -89,6 +91,7 @@ static int recv_from_daemon (guestfs_h *g, uint32_t *size_rtn, void **buf_rtn); static int accept_from_daemon (guestfs_h *g); static int check_peer_euid (guestfs_h *g, int sock, uid_t *rtn); static void close_handles (void); +static int qemu_supports (guestfs_h *g, const char *option); #define UNIX_PATH_MAX 108 @@ -150,6 +153,7 @@ struct guestfs_h int msg_next_serial; }; +gl_lock_define_initialized (static, handles_lock); static guestfs_h *handles = NULL; static int atexit_handler_set = 0; @@ -217,17 +221,15 @@ guestfs_create (void) */ g->msg_next_serial = 0x00123400; - /* Link the handles onto a global list. This is the one area - * where the library needs to be made thread-safe. (XXX) - */ - /* acquire mutex (XXX) */ + /* Link the handles onto a global list. */ + gl_lock_lock (handles_lock); g->next = handles; handles = g; if (!atexit_handler_set) { atexit (close_handles); atexit_handler_set = 1; } - /* release mutex (XXX) */ + gl_lock_unlock (handles_lock); if (g->verbose) fprintf (stderr, "new guestfs handle %p\n", g); @@ -312,7 +314,7 @@ guestfs_close (guestfs_h *g) /* Mark the handle as dead before freeing it. */ g->state = NO_HANDLE; - /* acquire mutex (XXX) */ + gl_lock_lock (handles_lock); if (handles == g) handles = g->next; else { @@ -320,7 +322,7 @@ guestfs_close (guestfs_h *g) ; gg->next = g->next; } - /* release mutex (XXX) */ + gl_lock_unlock (handles_lock); free (g->last_error); free (g->path); @@ -747,7 +749,8 @@ guestfs__config (guestfs_h *g, } int -guestfs__add_drive (guestfs_h *g, const char *filename) +guestfs__add_drive_with_if (guestfs_h *g, const char *filename, + const char *drive_if) { size_t len = strlen (filename) + 64; char buf[len]; @@ -770,12 +773,12 @@ guestfs__add_drive (guestfs_h *g, const char *filename) int fd = open (filename, O_RDONLY|O_DIRECT); if (fd >= 0) { close (fd); - snprintf (buf, len, "file=%s,cache=off,if=" DRIVE_IF, filename); + snprintf (buf, len, "file=%s,cache=off,if=%s", filename, drive_if); } else { fd = open (filename, O_RDONLY); if (fd >= 0) { close (fd); - snprintf (buf, len, "file=%s,if=" DRIVE_IF, filename); + snprintf (buf, len, "file=%s,if=%s", filename, drive_if); } else { perrorf (g, "%s", filename); return -1; @@ -786,11 +789,9 @@ guestfs__add_drive (guestfs_h *g, const char *filename) } int -guestfs__add_drive_ro (guestfs_h *g, const char *filename) +guestfs__add_drive_ro_with_if (guestfs_h *g, const char *filename, + const char *drive_if) { - size_t len = strlen (filename) + 64; - char buf[len]; - if (strchr (filename, ',') != NULL) { error (g, _("filename cannot contain ',' (comma) character")); return -1; @@ -801,12 +802,41 @@ guestfs__add_drive_ro (guestfs_h *g, const char *filename) return -1; } - snprintf (buf, len, "file=%s,snapshot=on,if=%s", filename, DRIVE_IF); + if (qemu_supports (g, NULL) == -1) + return -1; + + /* Only SCSI and virtio drivers support readonly mode. + * This is only supported as a QEMU feature since 2010/01. + */ + int supports_ro = 0; + if ((STREQ (drive_if, "scsi") || STREQ (drive_if, "virtio")) && + qemu_supports (g, "readonly=on")) + supports_ro = 1; + + size_t len = strlen (filename) + 100; + char buf[len]; + + snprintf (buf, len, "file=%s,snapshot=on,%sif=%s", + filename, + supports_ro ? "readonly=on," : "", + drive_if); return guestfs__config (g, "-drive", buf); } int +guestfs__add_drive (guestfs_h *g, const char *filename) +{ + return guestfs__add_drive_with_if (g, filename, DRIVE_IF); +} + +int +guestfs__add_drive_ro (guestfs_h *g, const char *filename) +{ + return guestfs__add_drive_ro_with_if (g, filename, DRIVE_IF); +} + +int guestfs__add_cdrom (guestfs_h *g, const char *filename) { if (strchr (filename, ',') != NULL) { @@ -855,8 +885,7 @@ dir_contains_files (const char *dir, ...) static void print_timestamped_message (guestfs_h *g, const char *fs, ...); static int build_supermin_appliance (guestfs_h *g, const char *path, char **kernel, char **initrd); -static int test_qemu (guestfs_h *g); -static int qemu_supports (guestfs_h *g, const char *option); +static int is_openable (guestfs_h *g, const char *path, int flags); static void print_cmdline (guestfs_h *g); static const char *kernel_name = "vmlinuz." REPO "." host_cpu; @@ -1007,7 +1036,7 @@ guestfs__launch (guestfs_h *g) print_timestamped_message (g, "begin testing qemu features"); /* Get qemu help text and version. */ - if (test_qemu (g) == -1) + if (qemu_supports (g, NULL) == -1) goto cleanup0; /* Choose which vmchannel implementation to use. */ @@ -1090,15 +1119,44 @@ guestfs__launch (guestfs_h *g) */ g->cmdline[0] = g->qemu; - snprintf (buf, sizeof buf, "%d", g->memsize); - add_cmdline (g, "-m"); - add_cmdline (g, buf); + /* qemu sometimes needs this option to enable hardware + * virtualization, but some versions of 'qemu-kvm' will use KVM + * regardless (even where this option appears in the help text). + * It is rumoured that there are versions of qemu where supplying + * this option when hardware virtualization is not available will + * cause qemu to fail, so we we have to check at least that + * /dev/kvm is openable. That's not reliable, since /dev/kvm + * might be openable by qemu but not by us (think: SELinux) in + * which case the user would not get hardware virtualization, + * although at least shouldn't fail. A giant clusterfuck with the + * qemu command line, again. + */ + if (qemu_supports (g, "-enable-kvm") && + is_openable (g, "/dev/kvm", O_RDWR)) + add_cmdline (g, "-enable-kvm"); + + /* Newer versions of qemu (from around 2009/12) changed the + * behaviour of monitors so that an implicit '-monitor stdio' is + * assumed if we are in -nographic mode and there is no other + * -monitor option. Only a single stdio device is allowed, so + * this broke the '-serial stdio' option. There is a new flag + * called -nodefaults which gets rid of all this default crud, so + * let's use that to avoid this and any future surprises. + */ + if (qemu_supports (g, "-nodefaults")) + add_cmdline (g, "-nodefaults"); - add_cmdline (g, "-no-reboot"); /* Force exit instead of reboot on panic */ add_cmdline (g, "-nographic"); add_cmdline (g, "-serial"); add_cmdline (g, "stdio"); + snprintf (buf, sizeof buf, "%d", g->memsize); + add_cmdline (g, "-m"); + add_cmdline (g, buf); + + /* Force exit instead of reboot on panic */ + add_cmdline (g, "-no-reboot"); + /* These options recommended by KVM developers to improve reliability. */ if (qemu_supports (g, "-no-hpet")) add_cmdline (g, "-no-hpet"); @@ -1492,9 +1550,12 @@ build_supermin_appliance (guestfs_h *g, const char *path, snprintf (cmd, sizeof cmd, "PATH='%s':$PATH " - "libguestfs-supermin-helper '%s' %s %s", + "libguestfs-supermin-helper%s '%s' " host_cpu " " REPO " %s %s", path, + g->verbose ? " --verbose" : "", path, *kernel, *initrd); + if (g->verbose) + print_timestamped_message (g, "%s", cmd); r = system (cmd); if (r == -1 || WEXITSTATUS(r) != 0) { @@ -1531,7 +1592,7 @@ print_timestamped_message (guestfs_h *g, const char *fs, ...) va_list args; char *msg; int err; - struct timeval tv, diff; + struct timeval tv; va_start (args, fs); err = vasprintf (&msg, fs, args); @@ -1559,12 +1620,7 @@ test_qemu (guestfs_h *g) char cmd[1024]; FILE *fp; - free (g->qemu_help); - free (g->qemu_version); - g->qemu_help = NULL; - g->qemu_version = NULL; - - snprintf (cmd, sizeof cmd, "LC_ALL=C '%s' -help", g->qemu); + snprintf (cmd, sizeof cmd, "LC_ALL=C '%s' -nographic -help", g->qemu); fp = popen (cmd, "r"); /* qemu -help should always work (qemu -version OTOH wasn't @@ -1586,7 +1642,8 @@ test_qemu (guestfs_h *g) if (pclose (fp) == -1) goto error; - snprintf (cmd, sizeof cmd, "LC_ALL=C '%s' -version 2>/dev/null", g->qemu); + snprintf (cmd, sizeof cmd, "LC_ALL=C '%s' -nographic -version 2>/dev/null", + g->qemu); fp = popen (cmd, "r"); if (fp) { @@ -1624,11 +1681,40 @@ read_all (guestfs_h *g, FILE *fp, char **ret) /* Test if option is supported by qemu command line (just by grepping * the help text). + * + * The first time this is used, it has to run the external qemu + * binary. If that fails, it returns -1. + * + * To just do the first-time run of the qemu binary, call this with + * option == NULL, in which case it will return -1 if there was an + * error doing that. */ static int qemu_supports (guestfs_h *g, const char *option) { - return g->qemu_help && strstr (g->qemu_help, option) != NULL; + if (!g->qemu_help) { + if (test_qemu (g) == -1) + return -1; + } + + if (option == NULL) + return 1; + + return strstr (g->qemu_help, option) != NULL; +} + +/* Check if a file can be opened. */ +static int +is_openable (guestfs_h *g, const char *path, int flags) +{ + int fd = open (path, flags); + if (fd == -1) { + if (g->verbose) + perror (path); + return 0; + } + close (fd); + return 1; } /* Check the peer effective UID for a TCP socket. Ideally we'd like @@ -2572,7 +2658,6 @@ guestfs___recv_file (guestfs_h *g, const char *filename) { void *buf; int fd, r; - size_t len; fd = open (filename, O_WRONLY|O_CREAT|O_TRUNC|O_NOCTTY, 0666); if (fd == -1) {