 6a67577d80
			
		
	
	
		6a67577d80
		
	
	
	
	
		
			
			romsize is an uint32_t variable. Specifying -1 as an uint32_t value is
obscure way to denote UINT32_MAX.
Worse, if int is wider than 32-bit, it will change the behavior of a
construct like the following:
romsize = -1;
if (romsize != -1) {
    ...
}
When -1 is assigned to romsize, -1 will be implicitly casted into
uint32_t, resulting in UINT32_MAX. On contrary, when evaluating
romsize != -1, romsize will be casted into int, and it will be a
comparison of UINT32_MAX and -1, and result in false.
Replace -1 with UINT32_MAX for statements involving the variable to
clarify the intent and prevent potential breakage.
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20240627-reuse-v10-10-7ca0b8ed3d9f@daynix.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
		
	
			
		
			
				
	
	
		
			93 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			93 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * This is splited from hw/i386/kvm/pci-assign.c
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|  */
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| #include "qemu/osdep.h"
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| #include "qapi/error.h"
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| #include "qemu/error-report.h"
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| #include "hw/loader.h"
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| #include "hw/pci/pci.h"
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| #include "xen_pt.h"
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| 
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| /*
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|  * Scan the assigned devices for the devices that have an option ROM, and then
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|  * load the corresponding ROM data to RAM. If an error occurs while loading an
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|  * option ROM, we just ignore that option ROM and continue with the next one.
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|  */
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| void *pci_assign_dev_load_option_rom(PCIDevice *dev,
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|                                      int *size, unsigned int domain,
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|                                      unsigned int bus, unsigned int slot,
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|                                      unsigned int function)
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| {
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|     char name[32], rom_file[64];
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|     FILE *fp;
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|     uint8_t val;
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|     struct stat st;
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|     void *ptr = NULL;
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|     Object *owner = OBJECT(dev);
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| 
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|     /* If loading ROM from file, pci handles it */
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|     if (dev->romfile || !dev->rom_bar) {
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|         return NULL;
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|     }
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| 
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|     snprintf(rom_file, sizeof(rom_file),
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|              "/sys/bus/pci/devices/%04x:%02x:%02x.%01x/rom",
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|              domain, bus, slot, function);
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| 
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|     /* Write "1" to the ROM file to enable it */
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|     fp = fopen(rom_file, "r+");
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|     if (fp == NULL) {
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|         if (errno != ENOENT) {
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|             error_report("pci-assign: Cannot open %s: %s", rom_file, strerror(errno));
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|         }
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|         return NULL;
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|     }
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|     if (fstat(fileno(fp), &st) == -1) {
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|         error_report("pci-assign: Cannot stat %s: %s", rom_file, strerror(errno));
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|         goto close_rom;
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|     }
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| 
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|     val = 1;
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|     if (fwrite(&val, 1, 1, fp) != 1) {
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|         goto close_rom;
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|     }
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|     fseek(fp, 0, SEEK_SET);
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| 
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|     if (dev->romsize != UINT_MAX) {
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|         if (st.st_size > dev->romsize) {
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|             error_report("ROM BAR \"%s\" (%ld bytes) is too large for ROM size %u",
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|                          rom_file, (long) st.st_size, dev->romsize);
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|             goto close_rom;
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|         }
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|     } else {
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|         dev->romsize = st.st_size;
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|     }
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| 
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|     snprintf(name, sizeof(name), "%s.rom", object_get_typename(owner));
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|     memory_region_init_ram(&dev->rom, owner, name, dev->romsize, &error_abort);
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|     ptr = memory_region_get_ram_ptr(&dev->rom);
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|     memset(ptr, 0xff, dev->romsize);
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| 
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|     if (!fread(ptr, 1, st.st_size, fp)) {
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|         error_report("pci-assign: Cannot read from host %s", rom_file);
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|         error_printf("Device option ROM contents are probably invalid "
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|                      "(check dmesg).\nSkip option ROM probe with rombar=0, "
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|                      "or load from file with romfile=\n");
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|         goto close_rom;
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|     }
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| 
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|     pci_register_bar(dev, PCI_ROM_SLOT, 0, &dev->rom);
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|     dev->has_rom = true;
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|     *size = st.st_size;
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| close_rom:
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|     /* Write "0" to disable ROM */
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|     fseek(fp, 0, SEEK_SET);
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|     val = 0;
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|     if (!fwrite(&val, 1, 1, fp)) {
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|         XEN_PT_WARN(dev, "%s\n", "Failed to disable pci-sysfs rom file");
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|     }
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|     fclose(fp);
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| 
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|     return ptr;
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| }
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