ia64/linux-2.6.18-xen.hg

view drivers/net/e2100.c @ 897:329ea0ccb344

balloon: try harder to balloon up under memory pressure.

Currently if the balloon driver is unable to increase the guest's
reservation it assumes the failure was due to reaching its full
allocation, gives up on the ballooning operation and records the limit
it reached as the "hard limit". The driver will not try again until
the target is set again (even to the same value).

However it is possible that ballooning has in fact failed due to
memory pressure in the host and therefore it is desirable to keep
attempting to reach the target in case memory becomes available. The
most likely scenario is that some guests are ballooning down while
others are ballooning up and therefore there is temporary memory
pressure while things stabilise. You would not expect a well behaved
toolstack to ask a domain to balloon to more than its allocation nor
would you expect it to deliberately over-commit memory by setting
balloon targets which exceed the total host memory.

This patch drops the concept of a hard limit and causes the balloon
driver to retry increasing the reservation on a timer in the same
manner as when decreasing the reservation.

Also if we partially succeed in increasing the reservation
(i.e. receive less pages than we asked for) then we may as well keep
those pages rather than returning them to Xen.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
author Keir Fraser <keir.fraser@citrix.com>
date Fri Jun 05 14:01:20 2009 +0100 (2009-06-05)
parents 831230e53067
children
line source
1 /* e2100.c: A Cabletron E2100 series ethernet driver for linux. */
2 /*
3 Written 1993-1994 by Donald Becker.
5 Copyright 1994 by Donald Becker.
6 Copyright 1993 United States Government as represented by the
7 Director, National Security Agency. This software may be used and
8 distributed according to the terms of the GNU General Public License,
9 incorporated herein by reference.
11 This is a driver for the Cabletron E2100 series ethercards.
13 The Author may be reached as becker@scyld.com, or C/O
14 Scyld Computing Corporation
15 410 Severn Ave., Suite 210
16 Annapolis MD 21403
18 The E2100 series ethercard is a fairly generic shared memory 8390
19 implementation. The only unusual aspect is the way the shared memory
20 registers are set: first you do an inb() in what is normally the
21 station address region, and the low three bits of next outb() *address*
22 is used as the write value for that register. Either someone wasn't
23 too used to dem bit en bites, or they were trying to obfuscate the
24 programming interface.
26 There is an additional complication when setting the window on the packet
27 buffer. You must first do a read into the packet buffer region with the
28 low 8 address bits the address setting the page for the start of the packet
29 buffer window, and then do the above operation. See mem_on() for details.
31 One bug on the chip is that even a hard reset won't disable the memory
32 window, usually resulting in a hung machine if mem_off() isn't called.
33 If this happens, you must power down the machine for about 30 seconds.
34 */
36 static const char version[] =
37 "e2100.c:v1.01 7/21/94 Donald Becker (becker@cesdis.gsfc.nasa.gov)\n";
39 #include <linux/module.h>
40 #include <linux/kernel.h>
41 #include <linux/errno.h>
42 #include <linux/string.h>
43 #include <linux/ioport.h>
44 #include <linux/netdevice.h>
45 #include <linux/etherdevice.h>
46 #include <linux/init.h>
47 #include <linux/delay.h>
49 #include <asm/io.h>
50 #include <asm/system.h>
52 #include "8390.h"
54 #define DRV_NAME "e2100"
56 static int e21_probe_list[] = {0x300, 0x280, 0x380, 0x220, 0};
58 /* Offsets from the base_addr.
59 Read from the ASIC register, and the low three bits of the next outb()
60 address is used to set the corresponding register. */
61 #define E21_NIC_OFFSET 0 /* Offset to the 8390 NIC. */
62 #define E21_ASIC 0x10
63 #define E21_MEM_ENABLE 0x10
64 #define E21_MEM_ON 0x05 /* Enable memory in 16 bit mode. */
65 #define E21_MEM_ON_8 0x07 /* Enable memory in 8 bit mode. */
66 #define E21_MEM_BASE 0x11
67 #define E21_IRQ_LOW 0x12 /* The low three bits of the IRQ number. */
68 #define E21_IRQ_HIGH 0x14 /* The high IRQ bit and media select ... */
69 #define E21_MEDIA 0x14 /* (alias). */
70 #define E21_ALT_IFPORT 0x02 /* Set to use the other (BNC,AUI) port. */
71 #define E21_BIG_MEM 0x04 /* Use a bigger (64K) buffer (we don't) */
72 #define E21_SAPROM 0x10 /* Offset to station address data. */
73 #define E21_IO_EXTENT 0x20
75 static inline void mem_on(short port, volatile char __iomem *mem_base,
76 unsigned char start_page )
77 {
78 /* This is a little weird: set the shared memory window by doing a
79 read. The low address bits specify the starting page. */
80 readb(mem_base+start_page);
81 inb(port + E21_MEM_ENABLE);
82 outb(E21_MEM_ON, port + E21_MEM_ENABLE + E21_MEM_ON);
83 }
85 static inline void mem_off(short port)
86 {
87 inb(port + E21_MEM_ENABLE);
88 outb(0x00, port + E21_MEM_ENABLE);
89 }
91 /* In other drivers I put the TX pages first, but the E2100 window circuitry
92 is designed to have a 4K Tx region last. The windowing circuitry wraps the
93 window at 0x2fff->0x0000 so that the packets at e.g. 0x2f00 in the RX ring
94 appear contiguously in the window. */
95 #define E21_RX_START_PG 0x00 /* First page of RX buffer */
96 #define E21_RX_STOP_PG 0x30 /* Last page +1 of RX ring */
97 #define E21_BIG_RX_STOP_PG 0xF0 /* Last page +1 of RX ring */
98 #define E21_TX_START_PG E21_RX_STOP_PG /* First page of TX buffer */
100 static int e21_probe1(struct net_device *dev, int ioaddr);
102 static int e21_open(struct net_device *dev);
103 static void e21_reset_8390(struct net_device *dev);
104 static void e21_block_input(struct net_device *dev, int count,
105 struct sk_buff *skb, int ring_offset);
106 static void e21_block_output(struct net_device *dev, int count,
107 const unsigned char *buf, int start_page);
108 static void e21_get_8390_hdr(struct net_device *dev, struct e8390_pkt_hdr *hdr,
109 int ring_page);
111 static int e21_close(struct net_device *dev);
114 /* Probe for the E2100 series ethercards. These cards have an 8390 at the
115 base address and the station address at both offset 0x10 and 0x18. I read
116 the station address from offset 0x18 to avoid the dataport of NE2000
117 ethercards, and look for Ctron's unique ID (first three octets of the
118 station address).
119 */
121 static int __init do_e2100_probe(struct net_device *dev)
122 {
123 int *port;
124 int base_addr = dev->base_addr;
125 int irq = dev->irq;
127 SET_MODULE_OWNER(dev);
129 if (base_addr > 0x1ff) /* Check a single specified location. */
130 return e21_probe1(dev, base_addr);
131 else if (base_addr != 0) /* Don't probe at all. */
132 return -ENXIO;
134 for (port = e21_probe_list; *port; port++) {
135 dev->irq = irq;
136 if (e21_probe1(dev, *port) == 0)
137 return 0;
138 }
140 return -ENODEV;
141 }
143 #ifndef MODULE
144 struct net_device * __init e2100_probe(int unit)
145 {
146 struct net_device *dev = alloc_ei_netdev();
147 int err;
149 if (!dev)
150 return ERR_PTR(-ENOMEM);
152 sprintf(dev->name, "eth%d", unit);
153 netdev_boot_setup_check(dev);
155 err = do_e2100_probe(dev);
156 if (err)
157 goto out;
158 return dev;
159 out:
160 free_netdev(dev);
161 return ERR_PTR(err);
162 }
163 #endif
165 static int __init e21_probe1(struct net_device *dev, int ioaddr)
166 {
167 int i, status, retval;
168 unsigned char *station_addr = dev->dev_addr;
169 static unsigned version_printed;
171 if (!request_region(ioaddr, E21_IO_EXTENT, DRV_NAME))
172 return -EBUSY;
174 /* First check the station address for the Ctron prefix. */
175 if (inb(ioaddr + E21_SAPROM + 0) != 0x00
176 || inb(ioaddr + E21_SAPROM + 1) != 0x00
177 || inb(ioaddr + E21_SAPROM + 2) != 0x1d) {
178 retval = -ENODEV;
179 goto out;
180 }
182 /* Verify by making certain that there is a 8390 at there. */
183 outb(E8390_NODMA + E8390_STOP, ioaddr);
184 udelay(1); /* we want to delay one I/O cycle - which is 2MHz */
185 status = inb(ioaddr);
186 if (status != 0x21 && status != 0x23) {
187 retval = -ENODEV;
188 goto out;
189 }
191 /* Read the station address PROM. */
192 for (i = 0; i < 6; i++)
193 station_addr[i] = inb(ioaddr + E21_SAPROM + i);
195 inb(ioaddr + E21_MEDIA); /* Point to media selection. */
196 outb(0, ioaddr + E21_ASIC); /* and disable the secondary interface. */
198 if (ei_debug && version_printed++ == 0)
199 printk(version);
201 for (i = 0; i < 6; i++)
202 printk(" %02X", station_addr[i]);
204 if (dev->irq < 2) {
205 int irqlist[] = {15,11,10,12,5,9,3,4}, i;
206 for (i = 0; i < 8; i++)
207 if (request_irq (irqlist[i], NULL, 0, "bogus", NULL) != -EBUSY) {
208 dev->irq = irqlist[i];
209 break;
210 }
211 if (i >= 8) {
212 printk(" unable to get IRQ %d.\n", dev->irq);
213 retval = -EAGAIN;
214 goto out;
215 }
216 } else if (dev->irq == 2) /* Fixup luser bogosity: IRQ2 is really IRQ9 */
217 dev->irq = 9;
219 /* The 8390 is at the base address. */
220 dev->base_addr = ioaddr;
222 ei_status.name = "E2100";
223 ei_status.word16 = 1;
224 ei_status.tx_start_page = E21_TX_START_PG;
225 ei_status.rx_start_page = E21_RX_START_PG;
226 ei_status.stop_page = E21_RX_STOP_PG;
227 ei_status.saved_irq = dev->irq;
229 /* Check the media port used. The port can be passed in on the
230 low mem_end bits. */
231 if (dev->mem_end & 15)
232 dev->if_port = dev->mem_end & 7;
233 else {
234 dev->if_port = 0;
235 inb(ioaddr + E21_MEDIA); /* Turn automatic media detection on. */
236 for(i = 0; i < 6; i++)
237 if (station_addr[i] != inb(ioaddr + E21_SAPROM + 8 + i)) {
238 dev->if_port = 1;
239 break;
240 }
241 }
243 /* Never map in the E21 shared memory unless you are actively using it.
244 Also, the shared memory has effective only one setting -- spread all
245 over the 128K region! */
246 if (dev->mem_start == 0)
247 dev->mem_start = 0xd0000;
249 ei_status.mem = ioremap(dev->mem_start, 2*1024);
250 if (!ei_status.mem) {
251 printk("unable to remap memory\n");
252 retval = -EAGAIN;
253 goto out;
254 }
256 #ifdef notdef
257 /* These values are unused. The E2100 has a 2K window into the packet
258 buffer. The window can be set to start on any page boundary. */
259 ei_status.rmem_start = dev->mem_start + TX_PAGES*256;
260 dev->mem_end = ei_status.rmem_end = dev->mem_start + 2*1024;
261 #endif
263 printk(", IRQ %d, %s media, memory @ %#lx.\n", dev->irq,
264 dev->if_port ? "secondary" : "primary", dev->mem_start);
266 ei_status.reset_8390 = &e21_reset_8390;
267 ei_status.block_input = &e21_block_input;
268 ei_status.block_output = &e21_block_output;
269 ei_status.get_8390_hdr = &e21_get_8390_hdr;
270 dev->open = &e21_open;
271 dev->stop = &e21_close;
272 #ifdef CONFIG_NET_POLL_CONTROLLER
273 dev->poll_controller = ei_poll;
274 #endif
275 NS8390_init(dev, 0);
277 retval = register_netdev(dev);
278 if (retval)
279 goto out;
280 return 0;
281 out:
282 release_region(ioaddr, E21_IO_EXTENT);
283 return retval;
284 }
286 static int
287 e21_open(struct net_device *dev)
288 {
289 short ioaddr = dev->base_addr;
290 int retval;
292 if ((retval = request_irq(dev->irq, ei_interrupt, 0, dev->name, dev)))
293 return retval;
295 /* Set the interrupt line and memory base on the hardware. */
296 inb(ioaddr + E21_IRQ_LOW);
297 outb(0, ioaddr + E21_ASIC + (dev->irq & 7));
298 inb(ioaddr + E21_IRQ_HIGH); /* High IRQ bit, and if_port. */
299 outb(0, ioaddr + E21_ASIC + (dev->irq > 7 ? 1:0)
300 + (dev->if_port ? E21_ALT_IFPORT : 0));
301 inb(ioaddr + E21_MEM_BASE);
302 outb(0, ioaddr + E21_ASIC + ((dev->mem_start >> 17) & 7));
304 ei_open(dev);
305 return 0;
306 }
308 static void
309 e21_reset_8390(struct net_device *dev)
310 {
311 short ioaddr = dev->base_addr;
313 outb(0x01, ioaddr);
314 if (ei_debug > 1) printk("resetting the E2180x3 t=%ld...", jiffies);
315 ei_status.txing = 0;
317 /* Set up the ASIC registers, just in case something changed them. */
319 if (ei_debug > 1) printk("reset done\n");
320 return;
321 }
323 /* Grab the 8390 specific header. We put the 2k window so the header page
324 appears at the start of the shared memory. */
326 static void
327 e21_get_8390_hdr(struct net_device *dev, struct e8390_pkt_hdr *hdr, int ring_page)
328 {
330 short ioaddr = dev->base_addr;
331 char __iomem *shared_mem = ei_status.mem;
333 mem_on(ioaddr, shared_mem, ring_page);
335 #ifdef notdef
336 /* Officially this is what we are doing, but the readl() is faster */
337 memcpy_fromio(hdr, shared_mem, sizeof(struct e8390_pkt_hdr));
338 #else
339 ((unsigned int*)hdr)[0] = readl(shared_mem);
340 #endif
342 /* Turn off memory access: we would need to reprogram the window anyway. */
343 mem_off(ioaddr);
345 }
347 /* Block input and output are easy on shared memory ethercards.
348 The E21xx makes block_input() especially easy by wrapping the top
349 ring buffer to the bottom automatically. */
350 static void
351 e21_block_input(struct net_device *dev, int count, struct sk_buff *skb, int ring_offset)
352 {
353 short ioaddr = dev->base_addr;
354 char __iomem *shared_mem = ei_status.mem;
356 mem_on(ioaddr, shared_mem, (ring_offset>>8));
358 /* Packet is always in one chunk -- we can copy + cksum. */
359 eth_io_copy_and_sum(skb, ei_status.mem + (ring_offset & 0xff), count, 0);
361 mem_off(ioaddr);
362 }
364 static void
365 e21_block_output(struct net_device *dev, int count, const unsigned char *buf,
366 int start_page)
367 {
368 short ioaddr = dev->base_addr;
369 volatile char __iomem *shared_mem = ei_status.mem;
371 /* Set the shared memory window start by doing a read, with the low address
372 bits specifying the starting page. */
373 readb(shared_mem + start_page);
374 mem_on(ioaddr, shared_mem, start_page);
376 memcpy_toio(shared_mem, buf, count);
377 mem_off(ioaddr);
378 }
380 static int
381 e21_close(struct net_device *dev)
382 {
383 short ioaddr = dev->base_addr;
385 if (ei_debug > 1)
386 printk("%s: Shutting down ethercard.\n", dev->name);
388 free_irq(dev->irq, dev);
389 dev->irq = ei_status.saved_irq;
391 /* Shut off the interrupt line and secondary interface. */
392 inb(ioaddr + E21_IRQ_LOW);
393 outb(0, ioaddr + E21_ASIC);
394 inb(ioaddr + E21_IRQ_HIGH); /* High IRQ bit, and if_port. */
395 outb(0, ioaddr + E21_ASIC);
397 ei_close(dev);
399 /* Double-check that the memory has been turned off, because really
400 really bad things happen if it isn't. */
401 mem_off(ioaddr);
403 return 0;
404 }
407 #ifdef MODULE
408 #define MAX_E21_CARDS 4 /* Max number of E21 cards per module */
409 static struct net_device *dev_e21[MAX_E21_CARDS];
410 static int io[MAX_E21_CARDS];
411 static int irq[MAX_E21_CARDS];
412 static int mem[MAX_E21_CARDS];
413 static int xcvr[MAX_E21_CARDS]; /* choose int. or ext. xcvr */
415 module_param_array(io, int, NULL, 0);
416 module_param_array(irq, int, NULL, 0);
417 module_param_array(mem, int, NULL, 0);
418 module_param_array(xcvr, int, NULL, 0);
419 MODULE_PARM_DESC(io, "I/O base address(es)");
420 MODULE_PARM_DESC(irq, "IRQ number(s)");
421 MODULE_PARM_DESC(mem, " memory base address(es)");
422 MODULE_PARM_DESC(xcvr, "transceiver(s) (0=internal, 1=external)");
423 MODULE_DESCRIPTION("Cabletron E2100 ISA ethernet driver");
424 MODULE_LICENSE("GPL");
426 /* This is set up so that only a single autoprobe takes place per call.
427 ISA device autoprobes on a running machine are not recommended. */
429 int __init init_module(void)
430 {
431 struct net_device *dev;
432 int this_dev, found = 0;
434 for (this_dev = 0; this_dev < MAX_E21_CARDS; this_dev++) {
435 if (io[this_dev] == 0) {
436 if (this_dev != 0) break; /* only autoprobe 1st one */
437 printk(KERN_NOTICE "e2100.c: Presently autoprobing (not recommended) for a single card.\n");
438 }
439 dev = alloc_ei_netdev();
440 if (!dev)
441 break;
442 dev->irq = irq[this_dev];
443 dev->base_addr = io[this_dev];
444 dev->mem_start = mem[this_dev];
445 dev->mem_end = xcvr[this_dev]; /* low 4bits = xcvr sel. */
446 if (do_e2100_probe(dev) == 0) {
447 dev_e21[found++] = dev;
448 continue;
449 }
450 free_netdev(dev);
451 printk(KERN_WARNING "e2100.c: No E2100 card found (i/o = 0x%x).\n", io[this_dev]);
452 break;
453 }
454 if (found)
455 return 0;
456 return -ENXIO;
457 }
459 static void cleanup_card(struct net_device *dev)
460 {
461 /* NB: e21_close() handles free_irq */
462 iounmap(ei_status.mem);
463 release_region(dev->base_addr, E21_IO_EXTENT);
464 }
466 void
467 cleanup_module(void)
468 {
469 int this_dev;
471 for (this_dev = 0; this_dev < MAX_E21_CARDS; this_dev++) {
472 struct net_device *dev = dev_e21[this_dev];
473 if (dev) {
474 unregister_netdev(dev);
475 cleanup_card(dev);
476 free_netdev(dev);
477 }
478 }
479 }
480 #endif /* MODULE */