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	 cfdbb712fb
			
		
	
	
		cfdbb712fb
		
	
	
	
	
		
			
			Now that the SystemMonitor queries which open files can be read and written to, having can_read()/can_write() unconditionally call ASSERT_NOT_REACHED() leads to system crashes when inspecting the WindowServer. Instead, just return true from can_read()/can_write() (indicating that the read()/write() syscalls should not block) and return -EINVAL when trying to actually read from or write to these devices.
		
			
				
	
	
		
			31 lines
		
	
	
	
		
			1.2 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			31 lines
		
	
	
	
		
			1.2 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
| #pragma once
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| 
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| #include <AK/String.h>
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| #include <AK/Types.h>
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| #include <Kernel/Devices/BlockDevice.h>
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| #include <Kernel/VM/PhysicalAddress.h>
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| 
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| class MBVGADevice final : public BlockDevice {
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|     AK_MAKE_ETERNAL
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| public:
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|     static MBVGADevice& the();
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| 
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|     MBVGADevice(PhysicalAddress addr, int pitch, int width, int height);
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| 
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|     virtual int ioctl(FileDescription&, unsigned request, unsigned arg) override;
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|     virtual KResultOr<Region*> mmap(Process&, FileDescription&, VirtualAddress preferred_vaddr, size_t offset, size_t, int prot) override;
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| 
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| private:
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|     virtual const char* class_name() const override { return "MBVGA"; }
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|     virtual bool can_read(const FileDescription&) const override { return true; }
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|     virtual bool can_write(const FileDescription&) const override { return true; }
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|     virtual ssize_t read(FileDescription&, u8*, ssize_t) override { return -EINVAL; }
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|     virtual ssize_t write(FileDescription&, const u8*, ssize_t) override { return -EINVAL; }
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| 
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|     size_t framebuffer_size_in_bytes() const { return m_framebuffer_pitch * m_framebuffer_height; }
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| 
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|     PhysicalAddress m_framebuffer_address;
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|     int m_framebuffer_pitch { 0 };
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|     int m_framebuffer_width { 0 };
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|     int m_framebuffer_height { 0 };
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| };
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