WebSVN – HelenOS – Diff – /trunk/kernel/genarch/src/mm/page_pt.c



 
    ptl0 = (pte_t *) PA2KA((uintptr_t) as->genarch.page_table);
 
    if (GET_PTL1_FLAGS(ptl0, PTL0_INDEX(page)) & PAGE_NOT_PRESENT) {
        newpt = (pte_t *)frame_alloc(PTL1_SIZE, FRAME_KA);
        memsetb(newpt, FRAME_SIZE << PTL1_SIZE, 0);
        SET_PTL1_ADDRESS(ptl0, PTL0_INDEX(page), KA2PA(newpt));
        SET_PTL1_FLAGS(ptl0, PTL0_INDEX(page), PAGE_PRESENT | PAGE_USER | PAGE_EXEC | PAGE_CACHEABLE | PAGE_WRITE);
    }
 
    ptl1 = (pte_t *) PA2KA(GET_PTL1_ADDRESS(ptl0, PTL0_INDEX(page)));
 
    if (GET_PTL2_FLAGS(ptl1, PTL1_INDEX(page)) & PAGE_NOT_PRESENT) {
        newpt = (pte_t *)frame_alloc(PTL2_SIZE, FRAME_KA);
        memsetb(newpt, FRAME_SIZE << PTL2_SIZE, 0);
        SET_PTL2_ADDRESS(ptl1, PTL1_INDEX(page), KA2PA(newpt));
        SET_PTL2_FLAGS(ptl1, PTL1_INDEX(page), PAGE_PRESENT | PAGE_USER | PAGE_EXEC | PAGE_CACHEABLE | PAGE_WRITE);
    }
 
    ptl2 = (pte_t *) PA2KA(GET_PTL2_ADDRESS(ptl1, PTL1_INDEX(page)));
 
    if (GET_PTL3_FLAGS(ptl2, PTL2_INDEX(page)) & PAGE_NOT_PRESENT) {
        newpt = (pte_t *)frame_alloc(PTL3_SIZE, FRAME_KA);
        memsetb(newpt, FRAME_SIZE << PTL3_SIZE, 0);
        SET_PTL3_ADDRESS(ptl2, PTL2_INDEX(page), KA2PA(newpt));
        SET_PTL3_FLAGS(ptl2, PTL2_INDEX(page), PAGE_PRESENT | PAGE_USER | PAGE_EXEC | PAGE_CACHEABLE | PAGE_WRITE);
    }
 
    ptl3 = (pte_t *) PA2KA(GET_PTL3_ADDRESS(ptl2, PTL2_INDEX(page)));

        return;
 
    ptl3 = (pte_t *) PA2KA(GET_PTL3_ADDRESS(ptl2, PTL2_INDEX(page)));
 
    /* Destroy the mapping. Setting to PAGE_NOT_PRESENT is not sufficient. */
    memsetb(&ptl3[PTL3_INDEX(page)], sizeof(pte_t), 0);
 
    /*
     * Second, free all empty tables along the way from PTL3 down to PTL0.
     */
   

         * PTL3 is empty.
         * Release the frame and remove PTL3 pointer from preceding table.
         */
        frame_free(KA2PA((uintptr_t) ptl3));
        if (PTL2_ENTRIES)
            memsetb(&ptl2[PTL2_INDEX(page)], sizeof(pte_t), 0);
        else if (PTL1_ENTRIES)
            memsetb(&ptl1[PTL1_INDEX(page)], sizeof(pte_t), 0);
        else
            memsetb(&ptl0[PTL0_INDEX(page)], sizeof(pte_t), 0);
    } else {
        /*
         * PTL3 is not empty.
         * Therefore, there must be a path from PTL0 to PTL3 and
         * thus nothing to free in higher levels.

             * PTL2 is empty.
             * Release the frame and remove PTL2 pointer from preceding table.
             */
            frame_free(KA2PA((uintptr_t) ptl2));
            if (PTL1_ENTRIES)
                memsetb(&ptl1[PTL1_INDEX(page)], sizeof(pte_t), 0);
            else
                memsetb(&ptl0[PTL0_INDEX(page)], sizeof(pte_t), 0);
        }
        else {
            /*
             * PTL2 is not empty.
             * Therefore, there must be a path from PTL0 to PTL2 and

            /*
             * PTL1 is empty.
             * Release the frame and remove PTL1 pointer from preceding table.
             */
            frame_free(KA2PA((uintptr_t) ptl1));
            memsetb(&ptl0[PTL0_INDEX(page)], sizeof(pte_t), 0);
        }
    }
 
}
 

Subversion Repositories HelenOS

(root)/trunk/kernel/genarch/src/mm/page_pt.c @ 1889 – Rev 2465 → 3104

Rev 2465		Rev 3104
Line 74...		Line 74...
74		74
75	ptl0 = (pte_t *) PA2KA((uintptr_t) as->genarch.page_table);	75	ptl0 = (pte_t *) PA2KA((uintptr_t) as->genarch.page_table);
76		76
77	if (GET_PTL1_FLAGS(ptl0, PTL0_INDEX(page)) & PAGE_NOT_PRESENT) {	77	if (GET_PTL1_FLAGS(ptl0, PTL0_INDEX(page)) & PAGE_NOT_PRESENT) {
78	newpt = (pte_t *)frame_alloc(PTL1_SIZE, FRAME_KA);	78	newpt = (pte_t *)frame_alloc(PTL1_SIZE, FRAME_KA);
79	memsetb((uintptr_t)newpt, FRAME_SIZE << PTL1_SIZE, 0);	79	memsetb(newpt, FRAME_SIZE << PTL1_SIZE, 0);
80	SET_PTL1_ADDRESS(ptl0, PTL0_INDEX(page), KA2PA(newpt));	80	SET_PTL1_ADDRESS(ptl0, PTL0_INDEX(page), KA2PA(newpt));
81	SET_PTL1_FLAGS(ptl0, PTL0_INDEX(page), PAGE_PRESENT \| PAGE_USER \| PAGE_EXEC \| PAGE_CACHEABLE \| PAGE_WRITE);	81	SET_PTL1_FLAGS(ptl0, PTL0_INDEX(page), PAGE_PRESENT \| PAGE_USER \| PAGE_EXEC \| PAGE_CACHEABLE \| PAGE_WRITE);
82	}	82	}
83		83
84	ptl1 = (pte_t *) PA2KA(GET_PTL1_ADDRESS(ptl0, PTL0_INDEX(page)));	84	ptl1 = (pte_t *) PA2KA(GET_PTL1_ADDRESS(ptl0, PTL0_INDEX(page)));
85		85
86	if (GET_PTL2_FLAGS(ptl1, PTL1_INDEX(page)) & PAGE_NOT_PRESENT) {	86	if (GET_PTL2_FLAGS(ptl1, PTL1_INDEX(page)) & PAGE_NOT_PRESENT) {
87	newpt = (pte_t *)frame_alloc(PTL2_SIZE, FRAME_KA);	87	newpt = (pte_t *)frame_alloc(PTL2_SIZE, FRAME_KA);
88	memsetb((uintptr_t)newpt, FRAME_SIZE << PTL2_SIZE, 0);	88	memsetb(newpt, FRAME_SIZE << PTL2_SIZE, 0);
89	SET_PTL2_ADDRESS(ptl1, PTL1_INDEX(page), KA2PA(newpt));	89	SET_PTL2_ADDRESS(ptl1, PTL1_INDEX(page), KA2PA(newpt));
90	SET_PTL2_FLAGS(ptl1, PTL1_INDEX(page), PAGE_PRESENT \| PAGE_USER \| PAGE_EXEC \| PAGE_CACHEABLE \| PAGE_WRITE);	90	SET_PTL2_FLAGS(ptl1, PTL1_INDEX(page), PAGE_PRESENT \| PAGE_USER \| PAGE_EXEC \| PAGE_CACHEABLE \| PAGE_WRITE);
91	}	91	}
92		92
93	ptl2 = (pte_t *) PA2KA(GET_PTL2_ADDRESS(ptl1, PTL1_INDEX(page)));	93	ptl2 = (pte_t *) PA2KA(GET_PTL2_ADDRESS(ptl1, PTL1_INDEX(page)));
94		94
95	if (GET_PTL3_FLAGS(ptl2, PTL2_INDEX(page)) & PAGE_NOT_PRESENT) {	95	if (GET_PTL3_FLAGS(ptl2, PTL2_INDEX(page)) & PAGE_NOT_PRESENT) {
96	newpt = (pte_t *)frame_alloc(PTL3_SIZE, FRAME_KA);	96	newpt = (pte_t *)frame_alloc(PTL3_SIZE, FRAME_KA);
97	memsetb((uintptr_t)newpt, FRAME_SIZE << PTL3_SIZE, 0);	97	memsetb(newpt, FRAME_SIZE << PTL3_SIZE, 0);
98	SET_PTL3_ADDRESS(ptl2, PTL2_INDEX(page), KA2PA(newpt));	98	SET_PTL3_ADDRESS(ptl2, PTL2_INDEX(page), KA2PA(newpt));
99	SET_PTL3_FLAGS(ptl2, PTL2_INDEX(page), PAGE_PRESENT \| PAGE_USER \| PAGE_EXEC \| PAGE_CACHEABLE \| PAGE_WRITE);	99	SET_PTL3_FLAGS(ptl2, PTL2_INDEX(page), PAGE_PRESENT \| PAGE_USER \| PAGE_EXEC \| PAGE_CACHEABLE \| PAGE_WRITE);
100	}	100	}
101		101
102	ptl3 = (pte_t *) PA2KA(GET_PTL3_ADDRESS(ptl2, PTL2_INDEX(page)));	102	ptl3 = (pte_t *) PA2KA(GET_PTL3_ADDRESS(ptl2, PTL2_INDEX(page)));
Line 144...		Line 144...
144	return;	144	return;
145		145
146	ptl3 = (pte_t *) PA2KA(GET_PTL3_ADDRESS(ptl2, PTL2_INDEX(page)));	146	ptl3 = (pte_t *) PA2KA(GET_PTL3_ADDRESS(ptl2, PTL2_INDEX(page)));
147		147
148	/* Destroy the mapping. Setting to PAGE_NOT_PRESENT is not sufficient. */	148	/* Destroy the mapping. Setting to PAGE_NOT_PRESENT is not sufficient. */
149	memsetb((uintptr_t) &ptl3[PTL3_INDEX(page)], sizeof(pte_t), 0);	149	memsetb(&ptl3[PTL3_INDEX(page)], sizeof(pte_t), 0);
150		150
151	/*	151	/*
152	* Second, free all empty tables along the way from PTL3 down to PTL0.	152	* Second, free all empty tables along the way from PTL3 down to PTL0.
153	*/	153	*/
154		154
Line 164...		Line 164...
164	* PTL3 is empty.	164	* PTL3 is empty.
165	* Release the frame and remove PTL3 pointer from preceding table.	165	* Release the frame and remove PTL3 pointer from preceding table.
166	*/	166	*/
167	frame_free(KA2PA((uintptr_t) ptl3));	167	frame_free(KA2PA((uintptr_t) ptl3));
168	if (PTL2_ENTRIES)	168	if (PTL2_ENTRIES)
169	memsetb((uintptr_t) &ptl2[PTL2_INDEX(page)], sizeof(pte_t), 0);	169	memsetb(&ptl2[PTL2_INDEX(page)], sizeof(pte_t), 0);
170	else if (PTL1_ENTRIES)	170	else if (PTL1_ENTRIES)
171	memsetb((uintptr_t) &ptl1[PTL1_INDEX(page)], sizeof(pte_t), 0);	171	memsetb(&ptl1[PTL1_INDEX(page)], sizeof(pte_t), 0);
172	else	172	else
173	memsetb((uintptr_t) &ptl0[PTL0_INDEX(page)], sizeof(pte_t), 0);	173	memsetb(&ptl0[PTL0_INDEX(page)], sizeof(pte_t), 0);
174	} else {	174	} else {
175	/*	175	/*
176	* PTL3 is not empty.	176	* PTL3 is not empty.
177	* Therefore, there must be a path from PTL0 to PTL3 and	177	* Therefore, there must be a path from PTL0 to PTL3 and
178	* thus nothing to free in higher levels.	178	* thus nothing to free in higher levels.
Line 193...		Line 193...
193	* PTL2 is empty.	193	* PTL2 is empty.
194	* Release the frame and remove PTL2 pointer from preceding table.	194	* Release the frame and remove PTL2 pointer from preceding table.
195	*/	195	*/
196	frame_free(KA2PA((uintptr_t) ptl2));	196	frame_free(KA2PA((uintptr_t) ptl2));
197	if (PTL1_ENTRIES)	197	if (PTL1_ENTRIES)
198	memsetb((uintptr_t) &ptl1[PTL1_INDEX(page)], sizeof(pte_t), 0);	198	memsetb(&ptl1[PTL1_INDEX(page)], sizeof(pte_t), 0);
199	else	199	else
200	memsetb((uintptr_t) &ptl0[PTL0_INDEX(page)], sizeof(pte_t), 0);	200	memsetb(&ptl0[PTL0_INDEX(page)], sizeof(pte_t), 0);
201	}	201	}
202	else {	202	else {
203	/*	203	/*
204	* PTL2 is not empty.	204	* PTL2 is not empty.
205	* Therefore, there must be a path from PTL0 to PTL2 and	205	* Therefore, there must be a path from PTL0 to PTL2 and
Line 221...		Line 221...
221	/*	221	/*
222	* PTL1 is empty.	222	* PTL1 is empty.
223	* Release the frame and remove PTL1 pointer from preceding table.	223	* Release the frame and remove PTL1 pointer from preceding table.
224	*/	224	*/
225	frame_free(KA2PA((uintptr_t) ptl1));	225	frame_free(KA2PA((uintptr_t) ptl1));
226	memsetb((uintptr_t) &ptl0[PTL0_INDEX(page)], sizeof(pte_t), 0);	226	memsetb(&ptl0[PTL0_INDEX(page)], sizeof(pte_t), 0);
227	}	227	}
228	}	228	}
229		229
230	}	230	}
231		231