1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
80 	 * Offset should be page aligned.  in sg_pager_alloc()
86 	 * The scatter/gather list must only include page-aligned  in sg_pager_alloc()
91 	for (i = 0; i < sg->sg_nseg; i++) {  in sg_pager_alloc()
92 		if ((sg->sg_segs[i].ss_paddr % PAGE_SIZE) != 0 ||  in sg_pager_alloc()
93 		    (sg->sg_segs[i].ss_len % PAGE_SIZE) != 0)  in sg_pager_alloc()
95 		npages += sg->sg_segs[i].ss_len / PAGE_SIZE;  in sg_pager_alloc()
117 	object->handle = sglist_hold(sg);  in sg_pager_alloc()
118 	TAILQ_INIT(&object->un_pager.sgp.sgp_pglist);  in sg_pager_alloc()
131 	while ((m = TAILQ_FIRST(&object->un_pager.sgp.sgp_pglist)) != 0) {  in sg_pager_dealloc()
134 		TAILQ_REMOVE(&object->un_pager.sgp.sgp_pglist, m, plinks.q);  in sg_pager_dealloc()
138 	sg = object->handle;  in sg_pager_dealloc()
140 	object->handle = NULL;  in sg_pager_dealloc()
141 	object->type = OBJT_DEAD;  in sg_pager_dealloc()
149 	vm_page_t m_paddr, page;  in sg_pager_getpages()  local
150 	vm_pindex_t offset;  in sg_pager_getpages()  local
159 	sg = object->handle;  in sg_pager_getpages()
160 	memattr = object->memattr;  in sg_pager_getpages()
161 	offset = m[0]->pindex;  in sg_pager_getpages()
164 	 * Lookup the physical address of the requested page.  An initial  in sg_pager_getpages()
166 	 * page is found since '0' can be a valid page-aligned physical  in sg_pager_getpages()
171 	for (i = 0; i < sg->sg_nseg; i++) {  in sg_pager_getpages()
172 		if (space + sg->sg_segs[i].ss_len <= (offset * PAGE_SIZE)) {  in sg_pager_getpages()
173 			space += sg->sg_segs[i].ss_len;  in sg_pager_getpages()
176 		paddr = sg->sg_segs[i].ss_paddr + offset * PAGE_SIZE - space;  in sg_pager_getpages()
179 	KASSERT(paddr != 1, ("invalid SG page index"));  in sg_pager_getpages()
181 	/* If "paddr" is a real page, perform a sanity check on "memattr". */  in sg_pager_getpages()
189 	/* Return a fake page for the requested page. */  in sg_pager_getpages()
190 	KASSERT(!(m[0]->flags & PG_FICTITIOUS),  in sg_pager_getpages()
191 	    ("backing page for SG is fake"));  in sg_pager_getpages()
193 	/* Construct a new fake page. */  in sg_pager_getpages()
194 	page = vm_page_getfake(paddr, memattr);  in sg_pager_getpages()
196 	TAILQ_INSERT_TAIL(&object->un_pager.sgp.sgp_pglist, page, plinks.q);  in sg_pager_getpages()
197 	vm_page_replace(page, object, offset, m[0]);  in sg_pager_getpages()
199 	m[0] = page;  in sg_pager_getpages()
200 	vm_page_valid(page);  in sg_pager_getpages()