[Question] Setting up an arbitrary virtual address space about vita-headers

[Princess-of-Sleeping]

Call ksceKernelAllocMemBlock with Settings VA to option.field_C and ATTR_VBASE to option.attr

#define ATTR_VBASE (1)

[Princess-of-Sleeping]

Also note that the kernel memory cannot be mapped to the user address because the process has its own address space.

Kern memory to User address `0x81010000`: Should failed
User memory to User address `0x81010000`: Should success
User memory to Kern address `0x01200000`: Should failed
Kern memory to Kern address `0x01200000`: Should success

[jvulcan]

Awesome, I'm investigating if I can mimic the available memory regions of the nintendo 3DS.
Because it doesn't expose dynamic addresses for heap, mappable memory, vram, mapped IO, etc.

#define OS_HEAP_AREA_BEGIN 0x08000000 ///< Start of the heap area in the virtual address space
#define OS_HEAP_AREA_END   0x0E000000 ///< End of the heap area in the virtual address space

#define OS_MAP_AREA_BEGIN  0x10000000 ///< Start of the mappable area in the virtual address space
#define OS_MAP_AREA_END    0x14000000 ///< End of the mappable area in the virtual address space

#define OS_OLD_FCRAM_VADDR 0x14000000 ///< Old pre-8.x linear FCRAM mapping virtual address
#define OS_OLD_FCRAM_SIZE  0x8000000  ///< Old pre-8.x linear FCRAM mapping size (128 MiB)

#define OS_QTMRAM_VADDR    0x1E800000 ///< New3DS QTM memory virtual address
#define OS_QTMRAM_SIZE     0x400000   ///< New3DS QTM memory size (4 MiB; last 128 KiB reserved by kernel)

#define OS_MMIO_VADDR      0x1EC00000 ///< Memory mapped IO range virtual address
#define OS_MMIO_SIZE       0x400000   ///< Memory mapped IO range size (4 MiB)

#define OS_VRAM_VADDR      0x1F000000 ///< VRAM virtual address
#define OS_VRAM_SIZE       0x600000   ///< VRAM size (6 MiB)

#define OS_DSPRAM_VADDR    0x1FF00000 ///< DSP memory virtual address
#define OS_DSPRAM_SIZE     0x80000    ///< DSP memory size (512 KiB)

#define OS_KERNELCFG_VADDR 0x1FF80000 ///< Kernel configuration page virtual address
#define OS_SHAREDCFG_VADDR 0x1FF81000 ///< Shared system configuration page virtual address

#define OS_FCRAM_VADDR     0x30000000 ///< Linear FCRAM mapping virtual address
#define OS_FCRAM_SIZE      0x10000000 ///< Linear FCRAM mapping size (256 MiB)

Edit: removed physical addresses because they don't matter

[jvulcan]

Thank you, I will keep researching about this topic further.

[jvulcan]

Call ksceKernelAllocMemBlock with Settings VA to option.field_C and ATTR_VBASE to option.attr

#define ATTR_VBASE (1)

Hello, I can't find "Settings VA" to fill field_C.
my code:

SceKernelAllocMemBlockKernelOpt opt;
opt.size = sizeof(SceKernelAllocMemBlockKernelOpt);
opt.field_C = 0x0; // ???? missing value
opt.attr = romMH4U.textVAddr; // virtual address is 0x100000

SceUID txtHndl = ksceKernelAllocMemBlock("3ds_text", 
SCE_KERNEL_MEMBLOCK_TYPE_KERNEL_RX, // should be kernel right?
romMH4U.textSz, opt);

Checked everything with "settings" in the documentation and I found nothing.
And another thing, why does the Alloc function asks for a name?

Thanks in advance.

[Princess-of-Sleeping]

SceKernelAllocMemBlockKernelOpt opt;
memset(&opt, 0, sizeof(opt));
opt.size = sizeof(opt);
opt.field_C = romMH4U.textVAddr;
opt.attr = ATTR_VBASE;

[jvulcan]

Thanks for the 'memset' note. I forgot to clear this thing in the first place; my c/c++ practical skill is a little rusted.