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Show First 20 Lines • Show All 578 Lines • ▼ Show 20 Lines	sf_buf_map(struct sf_buf *sf, int flags)
* virtual address from the TLB. Since the reference count for		* virtual address from the TLB. Since the reference count for
* the sf_buf's old mapping was zero, that mapping is not		* the sf_buf's old mapping was zero, that mapping is not
* currently in use. Consequently, there is no need to exchange		* currently in use. Consequently, there is no need to exchange
* the old and new PTEs atomically, even under PAE.		* the old and new PTEs atomically, even under PAE.
*/		*/
ptep = vtopte(sf->kva);		ptep = vtopte(sf->kva);
opte = *ptep;		opte = *ptep;
*ptep = VM_PAGE_TO_PHYS(sf->m) \| PG_RW \| PG_V \|		*ptep = VM_PAGE_TO_PHYS(sf->m) \| PG_RW \| PG_V \|
pmap_cache_bits(sf->m->md.pat_mode, 0);		pmap_cache_bits(kernel_pmap, sf->m->md.pat_mode, 0);

/*		/*
* Avoid unnecessary TLB invalidations: If the sf_buf's old		* Avoid unnecessary TLB invalidations: If the sf_buf's old
* virtual-to-physical mapping was not used, then any processor		* virtual-to-physical mapping was not used, then any processor
* that has invalidated the sf_buf's virtual address from its TLB		* that has invalidated the sf_buf's virtual address from its TLB
* since the last used mapping need not invalidate again.		* since the last used mapping need not invalidate again.
*/		*/
#ifdef SMP		#ifdef SMP
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