Commit | Line | Data |
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13849ba3 | 1 | /* kern_physio.c 6.2 83/09/09 */ |
961945a8 SL |
2 | |
3 | #include "../machine/pte.h" | |
663dbc72 BJ |
4 | |
5 | #include "../h/param.h" | |
6 | #include "../h/systm.h" | |
7 | #include "../h/dir.h" | |
8 | #include "../h/user.h" | |
9 | #include "../h/buf.h" | |
10 | #include "../h/conf.h" | |
11 | #include "../h/proc.h" | |
12 | #include "../h/seg.h" | |
663dbc72 | 13 | #include "../h/vm.h" |
973ecc4f | 14 | #include "../h/trace.h" |
d668d9ba | 15 | #include "../h/map.h" |
d6d7360b | 16 | #include "../h/uio.h" |
663dbc72 | 17 | |
663dbc72 BJ |
18 | /* |
19 | * Swap IO headers - | |
20 | * They contain the necessary information for the swap I/O. | |
21 | * At any given time, a swap header can be in three | |
22 | * different lists. When free it is in the free list, | |
23 | * when allocated and the I/O queued, it is on the swap | |
24 | * device list, and finally, if the operation was a dirty | |
25 | * page push, when the I/O completes, it is inserted | |
26 | * in a list of cleaned pages to be processed by the pageout daemon. | |
27 | */ | |
4c05b581 | 28 | struct buf *swbuf; |
663dbc72 | 29 | |
663dbc72 BJ |
30 | /* |
31 | * swap I/O - | |
32 | * | |
33 | * If the flag indicates a dirty page push initiated | |
34 | * by the pageout daemon, we map the page into the i th | |
35 | * virtual page of process 2 (the daemon itself) where i is | |
36 | * the index of the swap header that has been allocated. | |
37 | * We simply initialize the header and queue the I/O but | |
38 | * do not wait for completion. When the I/O completes, | |
39 | * iodone() will link the header to a list of cleaned | |
40 | * pages to be processed by the pageout daemon. | |
41 | */ | |
42 | swap(p, dblkno, addr, nbytes, rdflg, flag, dev, pfcent) | |
43 | struct proc *p; | |
44 | swblk_t dblkno; | |
45 | caddr_t addr; | |
39d536e6 | 46 | int nbytes, rdflg, flag; |
663dbc72 | 47 | dev_t dev; |
39d536e6 | 48 | u_int pfcent; |
663dbc72 BJ |
49 | { |
50 | register struct buf *bp; | |
e438ed8e | 51 | register u_int c; |
663dbc72 BJ |
52 | int p2dp; |
53 | register struct pte *dpte, *vpte; | |
530d0032 | 54 | int s; |
d668d9ba | 55 | extern swdone(); |
663dbc72 | 56 | |
530d0032 | 57 | s = spl6(); |
663dbc72 BJ |
58 | while (bswlist.av_forw == NULL) { |
59 | bswlist.b_flags |= B_WANTED; | |
60 | sleep((caddr_t)&bswlist, PSWP+1); | |
61 | } | |
62 | bp = bswlist.av_forw; | |
63 | bswlist.av_forw = bp->av_forw; | |
530d0032 | 64 | splx(s); |
663dbc72 BJ |
65 | |
66 | bp->b_flags = B_BUSY | B_PHYS | rdflg | flag; | |
67 | if ((bp->b_flags & (B_DIRTY|B_PGIN)) == 0) | |
68 | if (rdflg == B_READ) | |
69 | sum.v_pswpin += btoc(nbytes); | |
70 | else | |
71 | sum.v_pswpout += btoc(nbytes); | |
72 | bp->b_proc = p; | |
73 | if (flag & B_DIRTY) { | |
74 | p2dp = ((bp - swbuf) * CLSIZE) * KLMAX; | |
75 | dpte = dptopte(&proc[2], p2dp); | |
76 | vpte = vtopte(p, btop(addr)); | |
77 | for (c = 0; c < nbytes; c += NBPG) { | |
78 | if (vpte->pg_pfnum == 0 || vpte->pg_fod) | |
79 | panic("swap bad pte"); | |
80 | *dpte++ = *vpte++; | |
81 | } | |
d668d9ba SL |
82 | bp->b_un.b_addr = (caddr_t)ctob(dptov(&proc[2], p2dp)); |
83 | bp->b_flags |= B_CALL; | |
84 | bp->b_iodone = swdone; | |
85 | bp->b_pfcent = pfcent; | |
663dbc72 BJ |
86 | } else |
87 | bp->b_un.b_addr = addr; | |
88 | while (nbytes > 0) { | |
e438ed8e BJ |
89 | bp->b_bcount = nbytes; |
90 | minphys(bp); | |
91 | c = bp->b_bcount; | |
663dbc72 BJ |
92 | bp->b_blkno = dblkno; |
93 | bp->b_dev = dev; | |
53f9ca20 BJ |
94 | #ifdef TRACE |
95 | trace(TR_SWAPIO, dev, bp->b_blkno); | |
96 | #endif | |
ca1f746a | 97 | physstrat(bp, bdevsw[major(dev)].d_strategy, PSWP); |
663dbc72 BJ |
98 | if (flag & B_DIRTY) { |
99 | if (c < nbytes) | |
100 | panic("big push"); | |
663dbc72 BJ |
101 | return; |
102 | } | |
663dbc72 BJ |
103 | bp->b_un.b_addr += c; |
104 | bp->b_flags &= ~B_DONE; | |
105 | if (bp->b_flags & B_ERROR) { | |
106 | if ((flag & (B_UAREA|B_PAGET)) || rdflg == B_WRITE) | |
107 | panic("hard IO err in swap"); | |
108 | swkill(p, (char *)0); | |
109 | } | |
110 | nbytes -= c; | |
919fe934 | 111 | dblkno += btodb(c); |
663dbc72 | 112 | } |
530d0032 | 113 | s = spl6(); |
663dbc72 BJ |
114 | bp->b_flags &= ~(B_BUSY|B_WANTED|B_PHYS|B_PAGET|B_UAREA|B_DIRTY); |
115 | bp->av_forw = bswlist.av_forw; | |
116 | bswlist.av_forw = bp; | |
117 | if (bswlist.b_flags & B_WANTED) { | |
118 | bswlist.b_flags &= ~B_WANTED; | |
119 | wakeup((caddr_t)&bswlist); | |
120 | wakeup((caddr_t)&proc[2]); | |
121 | } | |
530d0032 | 122 | splx(s); |
663dbc72 BJ |
123 | } |
124 | ||
d668d9ba SL |
125 | /* |
126 | * Put a buffer on the clean list after I/O is done. | |
127 | * Called from biodone. | |
128 | */ | |
129 | swdone(bp) | |
130 | register struct buf *bp; | |
131 | { | |
132 | register int s; | |
133 | ||
134 | if (bp->b_flags & B_ERROR) | |
135 | panic("IO err in push"); | |
136 | s = spl6(); | |
137 | bp->av_forw = bclnlist; | |
138 | cnt.v_pgout++; | |
139 | cnt.v_pgpgout += bp->b_bcount / NBPG; | |
140 | bclnlist = bp; | |
141 | if (bswlist.b_flags & B_WANTED) | |
142 | wakeup((caddr_t)&proc[2]); | |
143 | splx(s); | |
144 | } | |
145 | ||
663dbc72 BJ |
146 | /* |
147 | * If rout == 0 then killed on swap error, else | |
148 | * rout is the name of the routine where we ran out of | |
149 | * swap space. | |
150 | */ | |
151 | swkill(p, rout) | |
152 | struct proc *p; | |
153 | char *rout; | |
154 | { | |
444f631c | 155 | char *mesg; |
663dbc72 | 156 | |
444f631c | 157 | printf("pid %d: ", p->p_pid); |
663dbc72 | 158 | if (rout) |
444f631c | 159 | printf(mesg = "killed due to no swap space\n"); |
663dbc72 | 160 | else |
444f631c BJ |
161 | printf(mesg = "killed on swap error\n"); |
162 | uprintf("sorry, pid %d was %s", p->p_pid, mesg); | |
663dbc72 BJ |
163 | /* |
164 | * To be sure no looping (e.g. in vmsched trying to | |
165 | * swap out) mark process locked in core (as though | |
166 | * done by user) after killing it so noone will try | |
167 | * to swap it out. | |
168 | */ | |
a30d2e97 | 169 | psignal(p, SIGKILL); |
663dbc72 BJ |
170 | p->p_flag |= SULOCK; |
171 | } | |
172 | ||
663dbc72 BJ |
173 | /* |
174 | * Raw I/O. The arguments are | |
175 | * The strategy routine for the device | |
176 | * A buffer, which will always be a special buffer | |
177 | * header owned exclusively by the device for this purpose | |
178 | * The device number | |
179 | * Read/write flag | |
180 | * Essentially all the work is computing physical addresses and | |
181 | * validating them. | |
182 | * If the user has the proper access privilidges, the process is | |
183 | * marked 'delayed unlock' and the pages involved in the I/O are | |
184 | * faulted and locked. After the completion of the I/O, the above pages | |
185 | * are unlocked. | |
186 | */ | |
d6d7360b BJ |
187 | physio(strat, bp, dev, rw, mincnt, uio) |
188 | int (*strat)(); | |
189 | register struct buf *bp; | |
190 | dev_t dev; | |
191 | int rw; | |
192 | unsigned (*mincnt)(); | |
193 | struct uio *uio; | |
663dbc72 | 194 | { |
406ddcbe | 195 | register struct iovec *iov = uio->uio_iov; |
663dbc72 BJ |
196 | register int c; |
197 | char *a; | |
d6d7360b | 198 | int s, error = 0; |
663dbc72 | 199 | |
d6d7360b | 200 | nextiov: |
406ddcbe | 201 | if (uio->uio_iovcnt == 0) |
d6d7360b | 202 | return (0); |
406ddcbe | 203 | if (useracc(iov->iov_base,(u_int)iov->iov_len,rw==B_READ?B_WRITE:B_READ) == NULL) |
d6d7360b | 204 | return (EFAULT); |
530d0032 | 205 | s = spl6(); |
663dbc72 BJ |
206 | while (bp->b_flags&B_BUSY) { |
207 | bp->b_flags |= B_WANTED; | |
208 | sleep((caddr_t)bp, PRIBIO+1); | |
209 | } | |
ef3b3d5a | 210 | splx(s); |
663dbc72 BJ |
211 | bp->b_error = 0; |
212 | bp->b_proc = u.u_procp; | |
d6d7360b BJ |
213 | bp->b_un.b_addr = iov->iov_base; |
214 | while (iov->iov_len > 0) { | |
663dbc72 BJ |
215 | bp->b_flags = B_BUSY | B_PHYS | rw; |
216 | bp->b_dev = dev; | |
919fe934 | 217 | bp->b_blkno = btodb(uio->uio_offset); |
d6d7360b | 218 | bp->b_bcount = iov->iov_len; |
663dbc72 BJ |
219 | (*mincnt)(bp); |
220 | c = bp->b_bcount; | |
221 | u.u_procp->p_flag |= SPHYSIO; | |
222 | vslock(a = bp->b_un.b_addr, c); | |
e438ed8e | 223 | physstrat(bp, strat, PRIBIO); |
81263dba | 224 | (void) spl6(); |
663dbc72 BJ |
225 | vsunlock(a, c, rw); |
226 | u.u_procp->p_flag &= ~SPHYSIO; | |
227 | if (bp->b_flags&B_WANTED) | |
228 | wakeup((caddr_t)bp); | |
530d0032 | 229 | splx(s); |
d6d7360b | 230 | c -= bp->b_resid; |
663dbc72 | 231 | bp->b_un.b_addr += c; |
d6d7360b BJ |
232 | iov->iov_len -= c; |
233 | uio->uio_resid -= c; | |
234 | uio->uio_offset += c; | |
961945a8 | 235 | /* temp kludge for tape drives */ |
35a494b8 | 236 | if (bp->b_resid || (bp->b_flags&B_ERROR)) |
52a593fa | 237 | break; |
663dbc72 BJ |
238 | } |
239 | bp->b_flags &= ~(B_BUSY|B_WANTED|B_PHYS); | |
d6d7360b | 240 | error = geterror(bp); |
961945a8 SL |
241 | /* temp kludge for tape drives */ |
242 | if (bp->b_resid || error) | |
d6d7360b | 243 | return (error); |
d6d7360b BJ |
244 | uio->uio_iov++; |
245 | uio->uio_iovcnt--; | |
246 | goto nextiov; | |
663dbc72 BJ |
247 | } |
248 | ||
35a494b8 SL |
249 | #define MAXPHYS (63 * 1024) |
250 | ||
663dbc72 BJ |
251 | unsigned |
252 | minphys(bp) | |
d6d7360b | 253 | struct buf *bp; |
663dbc72 BJ |
254 | { |
255 | ||
35a494b8 SL |
256 | if (bp->b_bcount > MAXPHYS) |
257 | bp->b_bcount = MAXPHYS; | |
663dbc72 | 258 | } |