 c5b309ff07
			
		
	
	
		c5b309ff07
		
	
	
	
	
		
			
			Main changes: - COW optimization for safecopy. - safemap, a grant-based interface for sharing memory regions between processes. - Integration with safemap and complete rework of DS, supporting new data types natively (labels, memory ranges, memory mapped ranges). - For further information: http://wiki.minix3.org/en/SummerOfCode2009/MemoryGrants Additional changes not included in the original Wu's branch: - Fixed unhandled case in VM when using COW optimization for safecopy in case of a block that has already been shared as SMAP. - Better interface and naming scheme for sys_saferevmap and ds_retrieve_map calls. - Better input checking in syslib: check for page alignment when creating memory mapping grants. - DS notifies subscribers when an entry is deleted. - Documented the behavior of indirect grants in case of memory mapping. - Test suite in /usr/src/test/safeperf|safecopy|safemap|ds/* reworked and extended. - Minor fixes and general cleanup. - TO-DO: Grant ids should be generated and managed the way endpoints are to make sure grant slots are never misreused.
		
			
				
	
	
		
			73 lines
		
	
	
		
			2.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			73 lines
		
	
	
		
			2.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| 
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| #include "syslib.h"
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| 
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| #include <minix/safecopies.h>
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| 
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| /*===========================================================================*
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|  *				sys_safemap				     *
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|  *===========================================================================*/
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| PUBLIC int sys_safemap(endpoint_t grantor, cp_grant_id_t grant,
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| 	vir_bytes grant_offset, vir_bytes my_address,
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| 	size_t bytes, int my_seg, int writable)
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| {
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| /* Map a block of data for which the other process has previously
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|  * granted permission. 
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|  */
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| 
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| 	message copy_mess;
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| 
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| 	copy_mess.SMAP_EP = grantor;
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| 	copy_mess.SMAP_GID = grant;
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| 	copy_mess.SMAP_OFFSET = grant_offset;
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| 	copy_mess.SMAP_SEG = (void*) my_seg;
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| 	copy_mess.SMAP_ADDRESS = my_address;
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| 	copy_mess.SMAP_BYTES = bytes;
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| 	copy_mess.SMAP_FLAG = writable;
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| 
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| 	return(_taskcall(SYSTASK, SYS_SAFEMAP, ©_mess));
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| 
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| }
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| 
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| /*===========================================================================*
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|  *			     sys_saferevmap_gid				     *
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|  *===========================================================================*/
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| PUBLIC int sys_saferevmap_gid(cp_grant_id_t grant)
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| {
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| /* Grantor revokes safemap by grant id. */
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| 	message copy_mess;
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| 
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| 	copy_mess.SMAP_FLAG = 1;
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| 	copy_mess.SMAP_GID = grant;
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| 
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| 	return(_taskcall(SYSTASK, SYS_SAFEREVMAP, ©_mess));
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| }
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| 
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| /*===========================================================================*
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|  *			    sys_saferevmap_addr				     *
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|  *===========================================================================*/
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| PUBLIC int sys_saferevmap_addr(vir_bytes addr)
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| {
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| /* Grantor revokes safemap by address. */
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| 	message copy_mess;
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| 
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| 	copy_mess.SMAP_FLAG = 0;
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| 	copy_mess.SMAP_GID = addr;
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| 
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| 	return(_taskcall(SYSTASK, SYS_SAFEREVMAP, ©_mess));
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| }
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| 
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| /*===========================================================================*
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|  *				sys_safeunmap				     *
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|  *===========================================================================*/
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| PUBLIC int sys_safeunmap(int my_seg, vir_bytes my_address)
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| {
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| /* Requestor unmaps safemap. */
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| 	message copy_mess;
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| 
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| 	copy_mess.SMAP_SEG = (void*) my_seg;
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| 	copy_mess.SMAP_ADDRESS = my_address;
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| 
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| 	return(_taskcall(SYSTASK, SYS_SAFEUNMAP, ©_mess));
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| }
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| 
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