Re: [Qemu-devel] multiple boot devices

["J. Mayer" <l_indien@magic.fr>]

[-- Attachment #1: Type: text/plain, Size: 2370 bytes --]


On Sat, 2007-11-03 at 01:18 +0000, Thiemo Seufer wrote:
> J. Mayer wrote:
> [snip]
> > > > It restricts the letter to the ones historically allowed by Qemu, not to
> > > > anything specific to any architecture or hw platform. What I like in my
> > > > implementation, compared to the strchr..., is that it exactly tells the
> > > > user which given device is incorrect.
> > > 
> > > Well, here it makes no difference, strchr tells you exactly same as much.
> > 
> > Yes, you're right. Was thinking about the original strspn.
> > 
> > > Instead of the check, the code could also allow everything from 'a' to
> > > 'z' and then just AND the produced 32bit bitmap with a machine defined
> > > bitmap that would be part of QEMUMachine.
> > 
> > I guess we would better stop at 'n', because we can easily define a
> > semantic for devices 'c' to 'm' (ie hard disk drives in a hardware
> > platform specific order) but we have to define what means 'o' to 'z'.
> > But I agree we would better extend it now, instead of having to rework
> > it later...
> 
> To select the network device to boot from would probably become a
> 'n' 'o' 'p' 'q' series.
> 
> [snip]
> > > > Here's a second pass cleanup, adding the machine dependant checks for
> > > > the PC machine and the PowerPC ones. As one can see, the OpenHack'Ware
> > > > firmware is able to boot from devices 'e' and 'f'. For the PowerPC
> > > > machines, I choosed to try to boot from the first given usable device,
> > > > some may not agree with this choice. It can be noticed that the
> > > > available boot devices are not the same for PowerPC PreP, g3bw and mac99
> > > > machines.
> > > > As I don't know the features and requirements for the other
> > > > architectures, I prefered not to add any check for those ones.
> > > 
> > > Most other machines ignore -boot and those that don't, shouldn't break
> > > from the introduced change, so please commit it when you feel ok with
> > > it.
> > 
> > I'd like to know what are the feelings around about this patch and if
> > there are specific requirements and/or problems for some platforms to be
> > addressed before...
> 
> I think the proposed scheme (and the implementation) is flexible enough
> to accomodate all relevant platforms.

Here's an updated patch that address the remark about network boot
devices.

-- 
J. Mayer <l_indien@magic.fr>
Never organized

[-- Attachment #2: boot_devices.diff --]
[-- Type: text/x-patch, Size: 12365 bytes --]

Index: vl.c
===================================================================
RCS file: /sources/qemu/qemu/vl.c,v
retrieving revision 1.353
diff -u -d -d -p -r1.353 vl.c
--- vl.c	31 Oct 2007 01:54:03 -0000	1.353
+++ vl.c	5 Nov 2007 12:07:05 -0000
@@ -162,12 +162,6 @@ static DisplayState display_state;
 int nographic;
 const char* keyboard_layout = NULL;
 int64_t ticks_per_sec;
-#if defined(TARGET_I386)
-#define MAX_BOOT_DEVICES 3
-#else
-#define MAX_BOOT_DEVICES 1
-#endif
-static char boot_device[MAX_BOOT_DEVICES + 1];
 int ram_size;
 int pit_min_timer_count = 0;
 int nb_nics;
@@ -7556,14 +7552,16 @@ int main(int argc, char **argv)
     int use_gdbstub;
     const char *gdbstub_port;
 #endif
+    uint32_t boot_devices_bitmap = 0;
     int i, cdrom_index, pflash_index;
-    int snapshot, linux_boot;
+    int snapshot, linux_boot, net_boot;
     const char *initrd_filename;
     const char *hd_filename[MAX_DISKS], *fd_filename[MAX_FD];
     const char *pflash_filename[MAX_PFLASH];
     const char *sd_filename;
     const char *mtd_filename;
     const char *kernel_filename, *kernel_cmdline;
+    const char *boot_devices = "";
     DisplayState *ds = &display_state;
     int cyls, heads, secs, translation;
     char net_clients[MAX_NET_CLIENTS][256];
@@ -7815,20 +7813,34 @@ int main(int argc, char **argv)
                 }
                 break;
             case QEMU_OPTION_boot:
-                if (strlen(optarg) > MAX_BOOT_DEVICES) {
-                    fprintf(stderr, "qemu: too many boot devices\n");
-                    exit(1);
-                }
-                strncpy(boot_device, optarg, MAX_BOOT_DEVICES);
-#if defined(TARGET_SPARC) || defined(TARGET_I386)
-#define BOOTCHARS "acdn"
-#else
-#define BOOTCHARS "acd"
-#endif
-                if (strlen(boot_device) != strspn(boot_device, BOOTCHARS)) {
-                    fprintf(stderr, "qemu: invalid boot device "
-                                    "sequence '%s'\n", boot_device);
-                    exit(1);
+                boot_devices = optarg;
+                /* We just do some generic consistency checks */
+                {
+                    /* Could easily be extended to 64 devices if needed */
+                    const unsigned char *p;
+                    
+                    boot_devices_bitmap = 0;
+                    for (p = boot_devices; *p != '\0'; p++) {
+                        /* Allowed boot devices are:
+                         * a b     : floppy disk drives
+                         * c ... f : IDE disk drives
+                         * g ... m : machine implementation dependant drives
+                         * n ... p : network devices
+                         * It's up to each machine implementation to check
+                         * if the given boot devices match the actual hardware
+                         * implementation and firmware features.
+                         */
+                        if (*p < 'a' || *p > 'q') {
+                            fprintf(stderr, "Invalid boot device '%c'\n", *p);
+                            exit(1);
+                        }
+                        if (boot_devices_bitmap & (1 << (*p - 'a'))) {
+                            fprintf(stderr,
+                                    "Boot device '%c' was given twice\n",*p);
+                            exit(1);
+                        }
+                        boot_devices_bitmap |= 1 << (*p - 'a');
+                    }
                 }
                 break;
             case QEMU_OPTION_fda:
@@ -8176,23 +8188,23 @@ int main(int argc, char **argv)
         kqemu_allowed = 0;
 #endif
     linux_boot = (kernel_filename != NULL);
-
-    if (!linux_boot &&
-        (!strchr(boot_device, 'n')) &&
+    net_boot = (boot_devices_bitmap >> ('n' - 'a')) && 0xF;
+    
+    /* XXX: this should not be: some embedded targets just have flash */
+    if (!linux_boot && net_boot == 0 &&
         hd_filename[0] == '\0' &&
         (cdrom_index >= 0 && hd_filename[cdrom_index] == '\0') &&
         fd_filename[0] == '\0')
         help(1);
 
     /* boot to floppy or the default cd if no hard disk defined yet */
-    if (!boot_device[0]) {
+    if (!boot_devices[0]) {
         if (hd_filename[0] != '\0')
-            boot_device[0] = 'c';
+            boot_devices = "c";
         else if (fd_filename[0] != '\0')
-            boot_device[0] = 'a';
+            boot_devices = "a";
         else
-            boot_device[0] = 'd';
-        boot_device[1] = 0;
+            boot_devices = "d";
     }
     setvbuf(stdout, NULL, _IOLBF, 0);
 
@@ -8232,20 +8244,28 @@ int main(int argc, char **argv)
     }
 
 #ifdef TARGET_I386
-    if (strchr(boot_device, 'n')) {
-	for (i = 0; i < nb_nics; i++) {
+    /* XXX: this should be moved in the PC machine instanciation code */
+    if (net_boot != 0) {
+        int netroms = 0;
+	for (i = 0; i < nb_nics && i < 4; i++) {
 	    const char *model = nd_table[i].model;
 	    char buf[1024];
-	    if (model == NULL)
-		model = "ne2k_pci";
-	    snprintf(buf, sizeof(buf), "%s/pxe-%s.bin", bios_dir, model);
-	    if (get_image_size(buf) > 0) {
-		option_rom[nb_option_roms] = strdup(buf);
-		nb_option_roms++;
-		break;
-	    }
+            if (net_boot & (1 << i)) {
+                if (model == NULL)
+                    model = "ne2k_pci";
+                snprintf(buf, sizeof(buf), "%s/pxe-%s.bin", bios_dir, model);
+                if (get_image_size(buf) > 0) {
+                    if (nb_option_roms >= MAX_OPTION_ROMS) {
+                        fprintf(stderr, "Too many option ROMs\n");
+                        exit(1);
+                    }
+                    option_rom[nb_option_roms] = strdup(buf);
+                    nb_option_roms++;
+                    netroms++;
+                }
+            }
 	}
-	if (i == nb_nics) {
+	if (netroms == 0) {
 	    fprintf(stderr, "No valid PXE rom found for network device\n");
 	    exit(1);
 	}
@@ -8425,7 +8445,7 @@ int main(int argc, char **argv)
         }
     }
 
-    machine->init(ram_size, vga_ram_size, boot_device,
+    machine->init(ram_size, vga_ram_size, boot_devices,
                   ds, fd_filename, snapshot,
                   kernel_filename, kernel_cmdline, initrd_filename, cpu_model);
 
Index: hw/pc.c
===================================================================
RCS file: /sources/qemu/qemu/hw/pc.c,v
retrieving revision 1.88
diff -u -d -d -p -r1.88 pc.c
--- hw/pc.c	31 Oct 2007 01:54:04 -0000	1.88
+++ hw/pc.c	5 Nov 2007 12:07:06 -0000
@@ -173,6 +173,7 @@ static int boot_device2nibble(char boot_
 static void cmos_init(int ram_size, const char *boot_device, BlockDriverState **hd_table)
 {
     RTCState *s = rtc_state;
+    int nbds, bds[3] = { 0, };
     int val;
     int fd0, fd1, nb;
     int i;
@@ -202,11 +203,22 @@ static void cmos_init(int ram_size, cons
     rtc_set_memory(s, 0x35, val >> 8);
 
     /* set boot devices, and disable floppy signature check if requested */
-    rtc_set_memory(s, 0x3d,
-            boot_device2nibble(boot_device[1]) << 4 |
-            boot_device2nibble(boot_device[0]) );
-    rtc_set_memory(s, 0x38,
-            boot_device2nibble(boot_device[2]) << 4 | (fd_bootchk ?  0x0 : 0x1));
+#define PC_MAX_BOOT_DEVICES 3
+    nbds = strlen(boot_device);
+    if (nbds > PC_MAX_BOOT_DEVICES) {
+        fprintf(stderr, "Too many boot devices for PC\n");
+        exit(1);
+    }
+    for (i = 0; i < nbds; i++) {
+        bds[i] = boot_device2nibble(boot_device[i]);
+        if (bds[i] == 0) {
+            fprintf(stderr, "Invalid boot device for PC: '%c'\n",
+                    boot_device[i]);
+            exit(1);
+        }
+    }
+    rtc_set_memory(s, 0x3d, (bds[1] << 4) | bds[0]);
+    rtc_set_memory(s, 0x38, (bds[2] << 4) | (fd_bootchk ?  0x0 : 0x1));
 
     /* floppy type */
 
Index: hw/ppc_chrp.c
===================================================================
RCS file: /sources/qemu/qemu/hw/ppc_chrp.c,v
retrieving revision 1.48
diff -u -d -d -p -r1.48 ppc_chrp.c
--- hw/ppc_chrp.c	4 Nov 2007 01:16:04 -0000	1.48
+++ hw/ppc_chrp.c	5 Nov 2007 12:07:06 -0000
@@ -66,7 +66,7 @@ static void ppc_core99_init (int ram_siz
     qemu_irq *dummy_irq;
     int pic_mem_index, dbdma_mem_index, cuda_mem_index;
     int ide_mem_index[2];
-    int ppc_boot_device = boot_device[0];
+    int ppc_boot_device;
 
     linux_boot = (kernel_filename != NULL);
 
@@ -178,6 +175,19 @@ static void ppc_core99_init (int ram_siz
         kernel_size = 0;
         initrd_base = 0;
         initrd_size = 0;
+        ppc_boot_device = '\0';
+        /* We consider that NewWorld PowerMac never have any floppy drive
+         * For now, OHW cannot boot from the network.
+         */
+        for (i = 0; i < boot_device[i] != '\0'; i++) {
+            ppc_boot_device = boot_device[i];
+            if (ppc_boot_device >= 'c' && ppc_boot_device <= 'f')
+                break;
+        }
+        if (ppc_boot_device == '\0') {
+            fprintf(stderr, "No valid boot device for Mac99 machine\n");
+            exit(1);
+        }
     }
 
     isa_mem_base = 0x80000000;
Index: hw/ppc_oldworld.c
===================================================================
RCS file: /sources/qemu/qemu/hw/ppc_oldworld.c,v
retrieving revision 1.4
diff -u -d -d -p -r1.4 ppc_oldworld.c
--- hw/ppc_oldworld.c	4 Nov 2007 01:16:04 -0000	1.4
+++ hw/ppc_oldworld.c	5 Nov 2007 12:07:06 -0000
@@ -114,7 +113,7 @@ static void ppc_heathrow_init (int ram_s
     int vga_bios_size, bios_size;
     qemu_irq *dummy_irq;
     int pic_mem_index, nvram_mem_index, dbdma_mem_index, cuda_mem_index;
-    int ppc_boot_device = boot_device[0];
+    int ppc_boot_device;
 
     linux_boot = (kernel_filename != NULL);
 
@@ -215,6 +214,25 @@ static void ppc_heathrow_init (int ram_s
         kernel_size = 0;
         initrd_base = 0;
         initrd_size = 0;
+        ppc_boot_device = '\0';
+        for (i = 0; i < boot_device[i] != '\0'; i++) {
+            ppc_boot_device = boot_device[i];
+            /* TOFIX: for now, the second IDE channel is not properly
+             *        emulated. The Mac floppy disk are not emulated.
+             *        For now, OHW cannot boot from the network.
+             */
+#if 0
+            if (ppc_boot_device >= 'a' && ppc_boot_device <= 'f')
+                break;
+#else
+            if (ppc_boot_device >= 'c' && ppc_boot_device <= 'd')
+                break;
+#endif
+        }
+        if (ppc_boot_device == '\0') {
+            fprintf(stderr, "No valid boot device for Mac99 machine\n");
+            exit(1);
+        }
     }
 
     isa_mem_base = 0x80000000;
Index: hw/ppc_prep.c
===================================================================
RCS file: /sources/qemu/qemu/hw/ppc_prep.c,v
retrieving revision 1.51
diff -u -d -d -p -r1.51 ppc_prep.c
--- hw/ppc_prep.c	31 Oct 2007 01:54:04 -0000	1.51
+++ hw/ppc_prep.c	5 Nov 2007 12:07:06 -0000
@@ -521,7 +521,8 @@ CPUReadMemoryFunc *PPC_prep_io_read[] = 
 #define NVRAM_SIZE        0x2000
 
 /* PowerPC PREP hardware initialisation */
-static void ppc_prep_init (int ram_size, int vga_ram_size, const char *boot_device,
+static void ppc_prep_init (int ram_size, int vga_ram_size,
+                           const char *boot_device,
                            DisplayState *ds, const char **fd_filename,
                            int snapshot, const char *kernel_filename,
                            const char *kernel_cmdline,
@@ -539,7 +540,7 @@ static void ppc_prep_init (int ram_size,
     ppc_def_t *def;
     PCIBus *pci_bus;
     qemu_irq *i8259;
-    int ppc_boot_device = boot_device[0];
+    int ppc_boot_device;
 
     sysctrl = qemu_mallocz(sizeof(sysctrl_t));
     if (sysctrl == NULL)
@@ -614,6 +615,17 @@ static void ppc_prep_init (int ram_size,
         kernel_size = 0;
         initrd_base = 0;
         initrd_size = 0;
+        ppc_boot_device = '\0';
+        /* For now, OHW cannot boot from the network. */
+        for (i = 0; i < boot_device[i] != '\0'; i++) {
+            ppc_boot_device = boot_device[i];
+            if (ppc_boot_device >= 'a' && ppc_boot_device <= 'f')
+                break;
+        }
+        if (ppc_boot_device == '\0') {
+            fprintf(stderr, "No valid boot device for Mac99 machine\n");
+            exit(1);
+        }
     }
 
     isa_mem_base = 0xc0000000;