Commit a720094d authored by Mel Gorman's avatar Mel Gorman
Browse files

mm: mempolicy: Hide MPOL_NOOP and MPOL_MF_LAZY from userspace for now 



The use of MPOL_NOOP and MPOL_MF_LAZY to allow an application to
explicitly request lazy migration is a good idea but the actual
API has not been well reviewed and once released we have to support it.
For now this patch prevents an application using the services. This
will need to be revisited.

Signed-off-by: default avatarMel Gorman <mgorman@suse.de>
parent 4b10e7d5

include/uapi/linux/mempolicy.h

+1 −3
Original line number Diff line number Diff line
@@ -21,7 +21,6 @@ enum { 
	MPOL_BIND,

	MPOL_INTERLEAVE,

	MPOL_LOCAL,

	MPOL_NOOP,		/* retain existing policy for range */

	MPOL_MAX,	/* always last member of enum */

};
@@ -57,8 +56,7 @@ enum mpol_rebind_step { 


#define MPOL_MF_VALID	(MPOL_MF_STRICT   | 	\

			 MPOL_MF_MOVE     | 	\

			 MPOL_MF_MOVE_ALL |	\

			 MPOL_MF_LAZY)

			 MPOL_MF_MOVE_ALL)



/*

 * Internal flags that share the struct mempolicy flags word with

mm/mempolicy.c

+4 −5
Original line number Diff line number Diff line
@@ -252,7 +252,7 @@ static struct mempolicy *mpol_new(unsigned short mode, unsigned short flags, 
	pr_debug("setting mode %d flags %d nodes[0] %lx\n",

		 mode, flags, nodes ? nodes_addr(*nodes)[0] : -1);



	if (mode == MPOL_DEFAULT || mode == MPOL_NOOP) {

	if (mode == MPOL_DEFAULT) {

		if (nodes && !nodes_empty(*nodes))

			return ERR_PTR(-EINVAL);

		return NULL;
@@ -1186,7 +1186,7 @@ static long do_mbind(unsigned long start, unsigned long len, 
	if (start & ~PAGE_MASK)

		return -EINVAL;



	if (mode == MPOL_DEFAULT || mode == MPOL_NOOP)

	if (mode == MPOL_DEFAULT)

		flags &= ~MPOL_MF_STRICT;



	len = (len + PAGE_SIZE - 1) & PAGE_MASK;
@@ -1241,7 +1241,7 @@ static long do_mbind(unsigned long start, unsigned long len, 
			  flags | MPOL_MF_INVERT, &pagelist);



	err = PTR_ERR(vma);	/* maybe ... */

	if (!IS_ERR(vma) && mode != MPOL_NOOP)

	if (!IS_ERR(vma))

		err = mbind_range(mm, start, end, new);



	if (!err) {
@@ -2530,7 +2530,6 @@ static const char * const policy_modes[] = 
	[MPOL_BIND]       = "bind",

	[MPOL_INTERLEAVE] = "interleave",

	[MPOL_LOCAL]      = "local",

	[MPOL_NOOP]	  = "noop",	/* should not actually be used */

};
@@ -2581,7 +2580,7 @@ int mpol_parse_str(char *str, struct mempolicy **mpol, int no_context) 
			break;

		}

	}

	if (mode >= MPOL_MAX || mode == MPOL_NOOP)

	if (mode >= MPOL_MAX)

		goto out;



	switch (mode) {

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