[PATCH 01/27] mtd: nand: fix drivers abusing mtd->priv

Boris Brezillon
2015-11-16T13:38:14Z

The ->priv field of the mtd_info object attached to a nand_chip device
should point to the nand_chip device. The pxa and cafe drivers are
assigning this field their own private structure, which works fine as long
as the nand_chip field is the first one in the driver private struct but
seems a bit fragile.
Fix that by setting mtd->priv to point the nand_chip field and assigning
chip->priv to the private structure head.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
---
drivers/mtd/nand/cafe_nand.c | 34 ++++++++++++++++++++++------------
drivers/mtd/nand/pxa3xx_nand.c | 30 +++++++++++++++++++-----------
2 files changed, 41 insertions(+), 23 deletions(-)

diff --git a/drivers/mtd/nand/cafe_nand.c b/drivers/mtd/nand/cafe_nand.c
index 9de78d2..cce3ac4 100644
--- a/drivers/mtd/nand/cafe_nand.c
+++ b/drivers/mtd/nand/cafe_nand.c
@@ -101,7 +101,8 @@ static const char *part_probes[] = { "cmdlinepart", "RedBoot", NULL };

static int cafe_device_ready(struct mtd_info *mtd)
{
- struct cafe_priv *cafe = mtd->priv;
+ struct nand_chip *chip = mtd->priv;
+ struct cafe_priv *cafe = chip->priv;
int result = !!(cafe_readl(cafe, NAND_STATUS) & 0x40000000);
uint32_t irqs = cafe_readl(cafe, NAND_IRQ);

@@ -117,7 +118,8 @@ static int cafe_device_ready(struct mtd_info *mtd)

static void cafe_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
{
- struct cafe_priv *cafe = mtd->priv;
+ struct nand_chip *chip = mtd->priv;
+ struct cafe_priv *cafe = chip->priv;

if (usedma)
memcpy(cafe->dmabuf + cafe->datalen, buf, len);
@@ -132,7 +134,8 @@ static void cafe_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)

static void cafe_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
{
- struct cafe_priv *cafe = mtd->priv;
+ struct nand_chip *chip = mtd->priv;
+ struct cafe_priv *cafe = chip->priv;

if (usedma)
memcpy(buf, cafe->dmabuf + cafe->datalen, len);
@@ -146,7 +149,8 @@ static void cafe_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)

static uint8_t cafe_read_byte(struct mtd_info *mtd)
{
- struct cafe_priv *cafe = mtd->priv;
+ struct nand_chip *chip = mtd->priv;
+ struct cafe_priv *cafe = chip->priv;
uint8_t d;

cafe_read_buf(mtd, &d, 1);
@@ -158,7 +162,8 @@ static uint8_t cafe_read_byte(struct mtd_info *mtd)
static void cafe_nand_cmdfunc(struct mtd_info *mtd, unsigned command,
int column, int page_addr)
{
- struct cafe_priv *cafe = mtd->priv;
+ struct nand_chip *chip = mtd->priv;
+ struct cafe_priv *cafe = chip->priv;
int adrbytes = 0;
uint32_t ctl1;
uint32_t doneint = 0x80000000;
@@ -313,7 +318,8 @@ static void cafe_nand_cmdfunc(struct mtd_info *mtd, unsigned command,

static void cafe_select_chip(struct mtd_info *mtd, int chipnr)
{
- struct cafe_priv *cafe = mtd->priv;
+ struct nand_chip *chip = mtd->priv;
+ struct cafe_priv *cafe = chip->priv;

cafe_dev_dbg(&cafe->pdev->dev, "select_chip %d\n", chipnr);

@@ -328,7 +334,8 @@ static void cafe_select_chip(struct mtd_info *mtd, int chipnr)
static irqreturn_t cafe_nand_interrupt(int irq, void *id)
{
struct mtd_info *mtd = id;
- struct cafe_priv *cafe = mtd->priv;
+ struct nand_chip *chip = mtd->priv;
+ struct cafe_priv *cafe = chip->priv;
uint32_t irqs = cafe_readl(cafe, NAND_IRQ);
cafe_writel(cafe, irqs & ~0x90000000, NAND_IRQ);
if (!irqs)
@@ -377,7 +384,7 @@ static int cafe_nand_read_oob(struct mtd_info *mtd, struct nand_chip *chip,
static int cafe_nand_read_page(struct mtd_info *mtd, struct nand_chip *chip,
uint8_t *buf, int oob_required, int page)
{
- struct cafe_priv *cafe = mtd->priv;
+ struct cafe_priv *cafe = chip->priv;
unsigned int max_bitflips = 0;

cafe_dev_dbg(&cafe->pdev->dev, "ECC result %08x SYN1,2 %08x\n",
@@ -519,7 +526,7 @@ static int cafe_nand_write_page_lowlevel(struct mtd_info *mtd,
const uint8_t *buf, int oob_required,
int page)
{
- struct cafe_priv *cafe = mtd->priv;
+ struct cafe_priv *cafe = chip->priv;

chip->write_buf(mtd, buf, mtd->writesize);
chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
@@ -604,7 +611,8 @@ static int cafe_nand_probe(struct pci_dev *pdev,
cafe = (void *)(&mtd[1]);

mtd->dev.parent = &pdev->dev;
- mtd->priv = cafe;
+ mtd->priv = &cafe->nand;
+ cafe->nand.priv = cafe;

cafe->pdev = pdev;
cafe->mmio = pci_iomap(pdev, 0, 0);
@@ -792,7 +800,8 @@ static int cafe_nand_probe(struct pci_dev *pdev,
static void cafe_nand_remove(struct pci_dev *pdev)
{
struct mtd_info *mtd = pci_get_drvdata(pdev);
- struct cafe_priv *cafe = mtd->priv;
+ struct nand_chip *chip = mtd->priv;
+ struct cafe_priv *cafe = chip->priv;

/* Disable NAND IRQ in global IRQ mask register */
cafe_writel(cafe, ~1 & cafe_readl(cafe, GLOBAL_IRQ_MASK), GLOBAL_IRQ_MASK);
@@ -819,7 +828,8 @@ static int cafe_nand_resume(struct pci_dev *pdev)
{
uint32_t ctrl;
struct mtd_info *mtd = pci_get_drvdata(pdev);
- struct cafe_priv *cafe = mtd->priv;
+ struct nand_chip *chip = mtd->priv;
+ struct cafe_priv *cafe = chip->priv;

/* Start off by resetting the NAND controller completely */
cafe_writel(cafe, 1, NAND_RESET);
diff --git a/drivers/mtd/nand/pxa3xx_nand.c b/drivers/mtd/nand/pxa3xx_nand.c
index 37df51d..ec421ad 100644
--- a/drivers/mtd/nand/pxa3xx_nand.c
+++ b/drivers/mtd/nand/pxa3xx_nand.c
@@ -1118,7 +1118,8 @@ static int prepare_set_command(struct pxa3xx_nand_info *info, int command,
static void nand_cmdfunc(struct mtd_info *mtd, unsigned command,
int column, int page_addr)
{
- struct pxa3xx_nand_host *host = mtd->priv;
+ struct nand_chip *chip = mtd->priv;
+ struct pxa3xx_nand_host *host = chip->priv;
struct pxa3xx_nand_info *info = host->info_data;
int exec_cmd;

@@ -1166,7 +1167,8 @@ static void nand_cmdfunc_extended(struct mtd_info *mtd,
const unsigned command,
int column, int page_addr)
{
- struct pxa3xx_nand_host *host = mtd->priv;
+ struct nand_chip *chip = mtd->priv;
+ struct pxa3xx_nand_host *host = chip->priv;
struct pxa3xx_nand_info *info = host->info_data;
int exec_cmd, ext_cmd_type;

@@ -1286,7 +1288,7 @@ static int pxa3xx_nand_read_page_hwecc(struct mtd_info *mtd,
struct nand_chip *chip, uint8_t *buf, int oob_required,
int page)
{
- struct pxa3xx_nand_host *host = mtd->priv;
+ struct pxa3xx_nand_host *host = chip->priv;
struct pxa3xx_nand_info *info = host->info_data;

chip->read_buf(mtd, buf, mtd->writesize);
@@ -1312,7 +1314,8 @@ static int pxa3xx_nand_read_page_hwecc(struct mtd_info *mtd,

static uint8_t pxa3xx_nand_read_byte(struct mtd_info *mtd)
{
- struct pxa3xx_nand_host *host = mtd->priv;
+ struct nand_chip *chip = mtd->priv;
+ struct pxa3xx_nand_host *host = chip->priv;
struct pxa3xx_nand_info *info = host->info_data;
char retval = 0xFF;

@@ -1325,7 +1328,8 @@ static uint8_t pxa3xx_nand_read_byte(struct mtd_info *mtd)

static u16 pxa3xx_nand_read_word(struct mtd_info *mtd)
{
- struct pxa3xx_nand_host *host = mtd->priv;
+ struct nand_chip *chip = mtd->priv;
+ struct pxa3xx_nand_host *host = chip->priv;
struct pxa3xx_nand_info *info = host->info_data;
u16 retval = 0xFFFF;

@@ -1338,7 +1342,8 @@ static u16 pxa3xx_nand_read_word(struct mtd_info *mtd)

static void pxa3xx_nand_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
{
- struct pxa3xx_nand_host *host = mtd->priv;
+ struct nand_chip *chip = mtd->priv;
+ struct pxa3xx_nand_host *host = chip->priv;
struct pxa3xx_nand_info *info = host->info_data;
int real_len = min_t(size_t, len, info->buf_count - info->buf_start);

@@ -1349,7 +1354,8 @@ static void pxa3xx_nand_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
static void pxa3xx_nand_write_buf(struct mtd_info *mtd,
const uint8_t *buf, int len)
{
- struct pxa3xx_nand_host *host = mtd->priv;
+ struct nand_chip *chip = mtd->priv;
+ struct pxa3xx_nand_host *host = chip->priv;
struct pxa3xx_nand_info *info = host->info_data;
int real_len = min_t(size_t, len, info->buf_count - info->buf_start);

@@ -1364,7 +1370,8 @@ static void pxa3xx_nand_select_chip(struct mtd_info *mtd, int chip)

static int pxa3xx_nand_waitfunc(struct mtd_info *mtd, struct nand_chip *this)
{
- struct pxa3xx_nand_host *host = mtd->priv;
+ struct nand_chip *chip = mtd->priv;
+ struct pxa3xx_nand_host *host = chip->priv;
struct pxa3xx_nand_info *info = host->info_data;

if (info->need_wait) {
@@ -1580,11 +1587,11 @@ static int pxa_ecc_init(struct pxa3xx_nand_info *info,

static int pxa3xx_nand_scan(struct mtd_info *mtd)
{
- struct pxa3xx_nand_host *host = mtd->priv;
+ struct nand_chip *chip = mtd->priv;
+ struct pxa3xx_nand_host *host = chip->priv;
struct pxa3xx_nand_info *info = host->info_data;
struct platform_device *pdev = info->pdev;
struct pxa3xx_nand_platform_data *pdata = dev_get_platdata(&pdev->dev);
- struct nand_chip *chip = mtd->priv;
int ret;
uint16_t ecc_strength, ecc_step;

@@ -1724,11 +1731,12 @@ static int alloc_nand_resource(struct platform_device *pdev)
host->mtd = mtd;
host->cs = cs;
host->info_data = info;
- mtd->priv = host;
+ mtd->priv = chip;
mtd->dev.parent = &pdev->dev;
/* FIXME: all chips use the same device tree partitions */
nand_set_flash_node(chip, np);

+ chip->priv = host;
chip->ecc.read_page = pxa3xx_nand_read_page_hwecc;
chip->ecc.write_page = pxa3xx_nand_write_page_hwecc;
chip->controller = &info->controller;
--
2.1.4