linux_dsm_epyc7002/drivers/mmc/core/sdio.c
Matt Fleming e881279363 sdio: initialise SDIO functions and update card->sdio_funcs in lockstep
Daniel Drake noticed a crash in the error path of mmc_attach_sdio().  This
bug is discussed at http://dev.laptop.org/ticket/9707.

BUG: unable to handle kernel paging request at 6b6b6c57
IP: [<b066d6e2>] sdio_remove_func+0x9/0x27
Call Trace:
[<b066cfb4>] ? mmc_sdio_remove+0x34/0x65
[<b066d1fc>] ? mmc_attach_sdio+0x217/0x240
[<b066a22f>] ? mmc_rescan+0x1a2/0x20f
[<b042e9a0>] ? worker_thread+0x156/0x1e

We need to accurately track how many SDIO functions have been initialised
(and keep card->sdio_funcs in sync) so that we don't try to remove more
functions than we initialised if we hit the error path in
mmc_attach_sdio().

Without this patch if we hit the error path in mmc_attach_sdio() we run
the risk of deferencing invalid memory in sdio_remove_func(), leading to a
crash.

Signed-off-by: Matt Fleming <matt@console-pimps.org>
Cc: Daniel Drake <dsd@laptop.org>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-17 15:45:31 -08:00

577 lines
11 KiB
C

/*
* linux/drivers/mmc/sdio.c
*
* Copyright 2006-2007 Pierre Ossman
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or (at
* your option) any later version.
*/
#include <linux/err.h>
#include <linux/mmc/host.h>
#include <linux/mmc/card.h>
#include <linux/mmc/sdio.h>
#include <linux/mmc/sdio_func.h>
#include "core.h"
#include "bus.h"
#include "sdio_bus.h"
#include "mmc_ops.h"
#include "sd_ops.h"
#include "sdio_ops.h"
#include "sdio_cis.h"
static int sdio_read_fbr(struct sdio_func *func)
{
int ret;
unsigned char data;
ret = mmc_io_rw_direct(func->card, 0, 0,
SDIO_FBR_BASE(func->num) + SDIO_FBR_STD_IF, 0, &data);
if (ret)
goto out;
data &= 0x0f;
if (data == 0x0f) {
ret = mmc_io_rw_direct(func->card, 0, 0,
SDIO_FBR_BASE(func->num) + SDIO_FBR_STD_IF_EXT, 0, &data);
if (ret)
goto out;
}
func->class = data;
out:
return ret;
}
static int sdio_init_func(struct mmc_card *card, unsigned int fn)
{
int ret;
struct sdio_func *func;
BUG_ON(fn > SDIO_MAX_FUNCS);
func = sdio_alloc_func(card);
if (IS_ERR(func))
return PTR_ERR(func);
func->num = fn;
ret = sdio_read_fbr(func);
if (ret)
goto fail;
ret = sdio_read_func_cis(func);
if (ret)
goto fail;
card->sdio_func[fn - 1] = func;
return 0;
fail:
/*
* It is okay to remove the function here even though we hold
* the host lock as we haven't registered the device yet.
*/
sdio_remove_func(func);
return ret;
}
static int sdio_read_cccr(struct mmc_card *card)
{
int ret;
int cccr_vsn;
unsigned char data;
memset(&card->cccr, 0, sizeof(struct sdio_cccr));
ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_CCCR, 0, &data);
if (ret)
goto out;
cccr_vsn = data & 0x0f;
if (cccr_vsn > SDIO_CCCR_REV_1_20) {
printk(KERN_ERR "%s: unrecognised CCCR structure version %d\n",
mmc_hostname(card->host), cccr_vsn);
return -EINVAL;
}
card->cccr.sdio_vsn = (data & 0xf0) >> 4;
ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_CAPS, 0, &data);
if (ret)
goto out;
if (data & SDIO_CCCR_CAP_SMB)
card->cccr.multi_block = 1;
if (data & SDIO_CCCR_CAP_LSC)
card->cccr.low_speed = 1;
if (data & SDIO_CCCR_CAP_4BLS)
card->cccr.wide_bus = 1;
if (cccr_vsn >= SDIO_CCCR_REV_1_10) {
ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_POWER, 0, &data);
if (ret)
goto out;
if (data & SDIO_POWER_SMPC)
card->cccr.high_power = 1;
}
if (cccr_vsn >= SDIO_CCCR_REV_1_20) {
ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_SPEED, 0, &data);
if (ret)
goto out;
if (data & SDIO_SPEED_SHS)
card->cccr.high_speed = 1;
}
out:
return ret;
}
static int sdio_enable_wide(struct mmc_card *card)
{
int ret;
u8 ctrl;
if (!(card->host->caps & MMC_CAP_4_BIT_DATA))
return 0;
if (card->cccr.low_speed && !card->cccr.wide_bus)
return 0;
ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_IF, 0, &ctrl);
if (ret)
return ret;
ctrl |= SDIO_BUS_WIDTH_4BIT;
ret = mmc_io_rw_direct(card, 1, 0, SDIO_CCCR_IF, ctrl, NULL);
if (ret)
return ret;
mmc_set_bus_width(card->host, MMC_BUS_WIDTH_4);
return 0;
}
/*
* If desired, disconnect the pull-up resistor on CD/DAT[3] (pin 1)
* of the card. This may be required on certain setups of boards,
* controllers and embedded sdio device which do not need the card's
* pull-up. As a result, card detection is disabled and power is saved.
*/
static int sdio_disable_cd(struct mmc_card *card)
{
int ret;
u8 ctrl;
if (!card->cccr.disable_cd)
return 0;
ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_IF, 0, &ctrl);
if (ret)
return ret;
ctrl |= SDIO_BUS_CD_DISABLE;
return mmc_io_rw_direct(card, 1, 0, SDIO_CCCR_IF, ctrl, NULL);
}
/*
* Test if the card supports high-speed mode and, if so, switch to it.
*/
static int sdio_enable_hs(struct mmc_card *card)
{
int ret;
u8 speed;
if (!(card->host->caps & MMC_CAP_SD_HIGHSPEED))
return 0;
if (!card->cccr.high_speed)
return 0;
ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_SPEED, 0, &speed);
if (ret)
return ret;
speed |= SDIO_SPEED_EHS;
ret = mmc_io_rw_direct(card, 1, 0, SDIO_CCCR_SPEED, speed, NULL);
if (ret)
return ret;
mmc_card_set_highspeed(card);
mmc_set_timing(card->host, MMC_TIMING_SD_HS);
return 0;
}
/*
* Handle the detection and initialisation of a card.
*
* In the case of a resume, "oldcard" will contain the card
* we're trying to reinitialise.
*/
static int mmc_sdio_init_card(struct mmc_host *host, u32 ocr,
struct mmc_card *oldcard)
{
struct mmc_card *card;
int err;
BUG_ON(!host);
WARN_ON(!host->claimed);
/*
* Inform the card of the voltage
*/
err = mmc_send_io_op_cond(host, host->ocr, &ocr);
if (err)
goto err;
/*
* For SPI, enable CRC as appropriate.
*/
if (mmc_host_is_spi(host)) {
err = mmc_spi_set_crc(host, use_spi_crc);
if (err)
goto err;
}
/*
* Allocate card structure.
*/
card = mmc_alloc_card(host, NULL);
if (IS_ERR(card)) {
err = PTR_ERR(card);
goto err;
}
card->type = MMC_TYPE_SDIO;
/*
* For native busses: set card RCA and quit open drain mode.
*/
if (!mmc_host_is_spi(host)) {
err = mmc_send_relative_addr(host, &card->rca);
if (err)
goto remove;
mmc_set_bus_mode(host, MMC_BUSMODE_PUSHPULL);
}
/*
* Select card, as all following commands rely on that.
*/
if (!mmc_host_is_spi(host)) {
err = mmc_select_card(card);
if (err)
goto remove;
}
/*
* Read the common registers.
*/
err = sdio_read_cccr(card);
if (err)
goto remove;
/*
* Read the common CIS tuples.
*/
err = sdio_read_common_cis(card);
if (err)
goto remove;
if (oldcard) {
int same = (card->cis.vendor == oldcard->cis.vendor &&
card->cis.device == oldcard->cis.device);
mmc_remove_card(card);
if (!same) {
err = -ENOENT;
goto err;
}
card = oldcard;
return 0;
}
/*
* Switch to high-speed (if supported).
*/
err = sdio_enable_hs(card);
if (err)
goto remove;
/*
* Change to the card's maximum speed.
*/
if (mmc_card_highspeed(card)) {
/*
* The SDIO specification doesn't mention how
* the CIS transfer speed register relates to
* high-speed, but it seems that 50 MHz is
* mandatory.
*/
mmc_set_clock(host, 50000000);
} else {
mmc_set_clock(host, card->cis.max_dtr);
}
/*
* Switch to wider bus (if supported).
*/
err = sdio_enable_wide(card);
if (err)
goto remove;
if (!oldcard)
host->card = card;
return 0;
remove:
if (!oldcard)
mmc_remove_card(card);
err:
return err;
}
/*
* Host is being removed. Free up the current card.
*/
static void mmc_sdio_remove(struct mmc_host *host)
{
int i;
BUG_ON(!host);
BUG_ON(!host->card);
for (i = 0;i < host->card->sdio_funcs;i++) {
if (host->card->sdio_func[i]) {
sdio_remove_func(host->card->sdio_func[i]);
host->card->sdio_func[i] = NULL;
}
}
mmc_remove_card(host->card);
host->card = NULL;
}
/*
* Card detection callback from host.
*/
static void mmc_sdio_detect(struct mmc_host *host)
{
int err;
BUG_ON(!host);
BUG_ON(!host->card);
mmc_claim_host(host);
/*
* Just check if our card has been removed.
*/
err = mmc_select_card(host->card);
mmc_release_host(host);
if (err) {
mmc_sdio_remove(host);
mmc_claim_host(host);
mmc_detach_bus(host);
mmc_release_host(host);
}
}
/*
* SDIO suspend. We need to suspend all functions separately.
* Therefore all registered functions must have drivers with suspend
* and resume methods. Failing that we simply remove the whole card.
*/
static int mmc_sdio_suspend(struct mmc_host *host)
{
int i, err = 0;
for (i = 0; i < host->card->sdio_funcs; i++) {
struct sdio_func *func = host->card->sdio_func[i];
if (func && sdio_func_present(func) && func->dev.driver) {
const struct dev_pm_ops *pmops = func->dev.driver->pm;
if (!pmops || !pmops->suspend || !pmops->resume) {
/* force removal of entire card in that case */
err = -ENOSYS;
} else
err = pmops->suspend(&func->dev);
if (err)
break;
}
}
while (err && --i >= 0) {
struct sdio_func *func = host->card->sdio_func[i];
if (func && sdio_func_present(func) && func->dev.driver) {
const struct dev_pm_ops *pmops = func->dev.driver->pm;
pmops->resume(&func->dev);
}
}
return err;
}
static int mmc_sdio_resume(struct mmc_host *host)
{
int i, err;
BUG_ON(!host);
BUG_ON(!host->card);
/* Basic card reinitialization. */
mmc_claim_host(host);
err = mmc_sdio_init_card(host, host->ocr, host->card);
mmc_release_host(host);
/*
* If the card looked to be the same as before suspending, then
* we proceed to resume all card functions. If one of them returns
* an error then we simply return that error to the core and the
* card will be redetected as new. It is the responsibility of
* the function driver to perform further tests with the extra
* knowledge it has of the card to confirm the card is indeed the
* same as before suspending (same MAC address for network cards,
* etc.) and return an error otherwise.
*/
for (i = 0; !err && i < host->card->sdio_funcs; i++) {
struct sdio_func *func = host->card->sdio_func[i];
if (func && sdio_func_present(func) && func->dev.driver) {
const struct dev_pm_ops *pmops = func->dev.driver->pm;
err = pmops->resume(&func->dev);
}
}
return err;
}
static const struct mmc_bus_ops mmc_sdio_ops = {
.remove = mmc_sdio_remove,
.detect = mmc_sdio_detect,
.suspend = mmc_sdio_suspend,
.resume = mmc_sdio_resume,
};
/*
* Starting point for SDIO card init.
*/
int mmc_attach_sdio(struct mmc_host *host, u32 ocr)
{
int err;
int i, funcs;
struct mmc_card *card;
BUG_ON(!host);
WARN_ON(!host->claimed);
mmc_attach_bus(host, &mmc_sdio_ops);
/*
* Sanity check the voltages that the card claims to
* support.
*/
if (ocr & 0x7F) {
printk(KERN_WARNING "%s: card claims to support voltages "
"below the defined range. These will be ignored.\n",
mmc_hostname(host));
ocr &= ~0x7F;
}
host->ocr = mmc_select_voltage(host, ocr);
/*
* Can we support the voltage(s) of the card(s)?
*/
if (!host->ocr) {
err = -EINVAL;
goto err;
}
/*
* Detect and init the card.
*/
err = mmc_sdio_init_card(host, host->ocr, NULL);
if (err)
goto err;
card = host->card;
/*
* The number of functions on the card is encoded inside
* the ocr.
*/
funcs = (ocr & 0x70000000) >> 28;
card->sdio_funcs = 0;
/*
* If needed, disconnect card detection pull-up resistor.
*/
err = sdio_disable_cd(card);
if (err)
goto remove;
/*
* Initialize (but don't add) all present functions.
*/
for (i = 0; i < funcs; i++, card->sdio_funcs++) {
err = sdio_init_func(host->card, i + 1);
if (err)
goto remove;
}
mmc_release_host(host);
/*
* First add the card to the driver model...
*/
err = mmc_add_card(host->card);
if (err)
goto remove_added;
/*
* ...then the SDIO functions.
*/
for (i = 0;i < funcs;i++) {
err = sdio_add_func(host->card->sdio_func[i]);
if (err)
goto remove_added;
}
return 0;
remove_added:
/* Remove without lock if the device has been added. */
mmc_sdio_remove(host);
mmc_claim_host(host);
remove:
/* And with lock if it hasn't been added. */
if (host->card)
mmc_sdio_remove(host);
err:
mmc_detach_bus(host);
mmc_release_host(host);
printk(KERN_ERR "%s: error %d whilst initialising SDIO card\n",
mmc_hostname(host), err);
return err;
}