[MTD][NOR] adding physical address to point()
Jörn Engel
joern at logfs.org
Wed Mar 5 07:00:29 EST 2008
Adding dwmw2 to Cc: can improve chances. ;)
On Wed, 5 March 2008 02:13:10 -0800, Jared Hulbert wrote:
>
> [MTD][NOR] adding physical address to point()
>
> Adding the ability to get a physical address from point() in addition
> to virtual address. This physical address is required for XIP of
> userspace code from flash.
>
> Signed-off-by: Jared Hulbert <jaredeh at gmail.com>
> Reviewed-by: Joern Engel <joern at logfs.org>
> ---
>
> We've looked at this before. Joern came up with the idea and I've
> been doing the patch. For a while I thought I could drop this patch.
> Turns out I do need it after all.
>
> Just to remind folks. I need this to do ANY legitimate XIP of
> userspace code from Flash. I've written AXFS to do XIP of userspace
> code. Working with the linux-mm guys we come up with a way to make
> mm/filemap_xip.c to what we need it to. To XIP Flash pages we need to
> do a vm_insert_pfn(). To get a pfn we need a physical address.
> virt_to_page() doesn't work for ioremap'ed kaddr's (like mtd->virt
> mtd->cached) and Linus told us "no sneaky page table walks and don't
> screw with virt_to_page()." So we're stuck needing to get this
> physical address from the mtd driver. This was the way we came up
> with to do that a while back.
>
> Any issues with this patch? It's same as it was plus some formating
> changes to pass checkpatch.pl. If we can merge this, it can be pulled
> from my mtd git tree on infradead.
>
> Please, I want to merge AXFS someday.
>
> drivers/mtd/devices/mtdram.c | 11 +++++++----
> drivers/mtd/devices/phram.c | 13 +++++++------
> drivers/mtd/devices/pmc551.c | 27 +++++++++++++++++----------
> drivers/mtd/devices/slram.c | 15 ++++++++++-----
> drivers/mtd/maps/uclinux.c | 6 ++++--
> drivers/mtd/mtdpart.c | 8 ++++----
> fs/jffs2/erase.c | 7 ++++---
> fs/jffs2/readinode.c | 9 +++++----
> fs/jffs2/scan.c | 7 ++++---
> include/linux/mtd/mtd.h | 6 ++++--
> include/linux/mtd/pmc551.h | 5 +++--
> drivers/mtd/chips/cfi_cmdset_0001.c | 14 ++++++++------
> 12 files changed, 77 insertions(+), 51 deletions(-)
>
> diff --git
> a/drivers/mtd/chips/cfi_cmdset_0001.c b/drivers/mtd/chips/cfi_cmdset_0001.c
> index 47794d2..d2105aa 100644
> --- a/drivers/mtd/chips/cfi_cmdset_0001.c
> +++ b/drivers/mtd/chips/cfi_cmdset_0001.c
> @@ -82,9 +82,8 @@ static struct mtd_info *cfi_intelext_setup (struct
> mtd_info *);
> static int cfi_intelext_partition_fixup(struct mtd_info *, struct
> cfi_private **);
>
> static int cfi_intelext_point (struct mtd_info *mtd, loff_t from, size_t len,
> - size_t *retlen, u_char **mtdbuf);
> -static void cfi_intelext_unpoint (struct mtd_info *mtd, u_char *addr,
> loff_t from,
> - size_t len);
> + size_t *retlen, void **virt, resource_size_t *phys);
> +static void cfi_intelext_unpoint(struct mtd_info *mtd, loff_t from,
> size_t len);
>
> static int chip_ready (struct map_info *map, struct flchip *chip,
> unsigned long adr, int mode);
> static int get_chip(struct map_info *map, struct flchip *chip,
> unsigned long adr, int mode);
> @@ -1237,7 +1236,8 @@ static int do_point_onechip (struct map_info
> *map, struct flchip *chip, loff_t a
> return ret;
> }
>
> -static int cfi_intelext_point (struct mtd_info *mtd, loff_t from,
> size_t len, size_t *retlen, u_char **mtdbuf)
> +static int cfi_intelext_point(struct mtd_info *mtd, loff_t from, size_t len,
> + size_t *retlen, void **virt, resource_size_t *phys)
> {
> struct map_info *map = mtd->priv;
> struct cfi_private *cfi = map->fldrv_priv;
> @@ -1254,8 +1254,10 @@ static int cfi_intelext_point (struct mtd_info
> *mtd, loff_t from, size_t len, si
> chipnum = (from >> cfi->chipshift);
> ofs = from - (chipnum << cfi->chipshift);
>
> - *mtdbuf = (void *)map->virt + cfi->chips[chipnum].start + ofs;
> + *virt = map->virt + cfi->chips[chipnum].start + ofs;
> *retlen = 0;
> + if (phys)
> + *phys = map->phys + cfi->chips[chipnum].start + ofs;
>
> while (len) {
> unsigned long thislen;
> @@ -1288,7 +1290,7 @@ static int cfi_intelext_point (struct mtd_info
> *mtd, loff_t from, size_t len, si
> return 0;
> }
>
> -static void cfi_intelext_unpoint (struct mtd_info *mtd, u_char *addr,
> loff_t from, size_t len)
> +static void cfi_intelext_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
> {
> struct map_info *map = mtd->priv;
> struct cfi_private *cfi = map->fldrv_priv;
> diff --git a/drivers/mtd/devices/mtdram.c b/drivers/mtd/devices/mtdram.c
> index e427c82..fe39a9d 100644
> --- a/drivers/mtd/devices/mtdram.c
> +++ b/drivers/mtd/devices/mtdram.c
> @@ -47,18 +47,21 @@ static int ram_erase(struct mtd_info *mtd, struct
> erase_info *instr)
> }
>
> static int ram_point(struct mtd_info *mtd, loff_t from, size_t len,
> - size_t *retlen, u_char **mtdbuf)
> + size_t *retlen, void **virt, resource_size_t *phys)
> {
> if (from + len > mtd->size)
> return -EINVAL;
>
> - *mtdbuf = mtd->priv + from;
> + /* can we return a physical address with this driver? */
> + if (phys)
> + return -EINVAL;
> +
> + *virt = mtd->priv + from;
> *retlen = len;
> return 0;
> }
>
> -static void ram_unpoint(struct mtd_info *mtd, u_char * addr, loff_t from,
> - size_t len)
> +static void ram_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
> {
> }
>
> diff --git a/drivers/mtd/devices/phram.c b/drivers/mtd/devices/phram.c
> index 180298b..2b4d739 100644
> --- a/drivers/mtd/devices/phram.c
> +++ b/drivers/mtd/devices/phram.c
> @@ -57,20 +57,21 @@ static int phram_erase(struct mtd_info *mtd,
> struct erase_info *instr)
> }
>
> static int phram_point(struct mtd_info *mtd, loff_t from, size_t len,
> - size_t *retlen, u_char **mtdbuf)
> + size_t *retlen, void **virt, resource_size_t *phys)
> {
> - u_char *start = mtd->priv;
> -
> if (from + len > mtd->size)
> return -EINVAL;
>
> - *mtdbuf = start + from;
> + /* can we return a physical address with this driver? */
> + if (phys)
> + return -EINVAL;
> +
> + *virt = mtd->priv + from;
> *retlen = len;
> return 0;
> }
>
> -static void phram_unpoint(struct mtd_info *mtd, u_char *addr, loff_t from,
> - size_t len)
> +static void phram_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
> {
> }
>
> diff --git a/drivers/mtd/devices/pmc551.c b/drivers/mtd/devices/pmc551.c
> index 7060a08..bc99817 100644
> --- a/drivers/mtd/devices/pmc551.c
> +++ b/drivers/mtd/devices/pmc551.c
> @@ -134,7 +134,8 @@ static int pmc551_erase(struct mtd_info *mtd,
> struct erase_info *instr)
> eoff_lo = end & (priv->asize - 1);
> soff_lo = instr->addr & (priv->asize - 1);
>
> - pmc551_point(mtd, instr->addr, instr->len, &retlen, &ptr);
> + pmc551_point(mtd, instr->addr, instr->len, &retlen,
> + (void **)&ptr, NULL);
>
> if (soff_hi == eoff_hi || mtd->size == priv->asize) {
> /* The whole thing fits within one access, so just one shot
> @@ -154,7 +155,8 @@ static int pmc551_erase(struct mtd_info *mtd,
> struct erase_info *instr)
> }
> soff_hi += priv->asize;
> pmc551_point(mtd, (priv->base_map0 | soff_hi),
> - priv->asize, &retlen, &ptr);
> + priv->asize, &retlen,
> + (void **)&ptr, NULL);
> }
> memset(ptr, 0xff, eoff_lo);
> }
> @@ -170,7 +172,7 @@ static int pmc551_erase(struct mtd_info *mtd,
> struct erase_info *instr)
> }
>
> static int pmc551_point(struct mtd_info *mtd, loff_t from, size_t len,
> - size_t * retlen, u_char ** mtdbuf)
> + size_t *retlen, void **virt, resource_size_t *phys)
> {
> struct mypriv *priv = mtd->priv;
> u32 soff_hi;
> @@ -188,6 +190,10 @@ static int pmc551_point(struct mtd_info *mtd,
> loff_t from, size_t len,
> return -EINVAL;
> }
>
> + /* can we return a physical address with this driver? */
> + if (phys)
> + return -EINVAL;
> +
> soff_hi = from & ~(priv->asize - 1);
> soff_lo = from & (priv->asize - 1);
>
> @@ -198,13 +204,12 @@ static int pmc551_point(struct mtd_info *mtd,
> loff_t from, size_t len,
> priv->curr_map0 = soff_hi;
> }
>
> - *mtdbuf = priv->start + soff_lo;
> + *virt = priv->start + soff_lo;
> *retlen = len;
> return 0;
> }
>
> -static void pmc551_unpoint(struct mtd_info *mtd, u_char * addr, loff_t from,
> - size_t len)
> +static void pmc551_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
> {
> #ifdef CONFIG_MTD_PMC551_DEBUG
> printk(KERN_DEBUG "pmc551_unpoint()\n");
> @@ -242,7 +247,7 @@ static int pmc551_read(struct mtd_info *mtd,
> loff_t from, size_t len,
> soff_lo = from & (priv->asize - 1);
> eoff_lo = end & (priv->asize - 1);
>
> - pmc551_point(mtd, from, len, retlen, &ptr);
> + pmc551_point(mtd, from, len, retlen, (void **)&ptr, NULL);
>
> if (soff_hi == eoff_hi) {
> /* The whole thing fits within one access, so just one shot
> @@ -263,7 +268,8 @@ static int pmc551_read(struct mtd_info *mtd,
> loff_t from, size_t len,
> goto out;
> }
> soff_hi += priv->asize;
> - pmc551_point(mtd, soff_hi, priv->asize, retlen, &ptr);
> + pmc551_point(mtd, soff_hi, priv->asize, retlen,
> + (void **)&ptr, NULL);
> }
> memcpy(copyto, ptr, eoff_lo);
> copyto += eoff_lo;
> @@ -308,7 +314,7 @@ static int pmc551_write(struct mtd_info *mtd,
> loff_t to, size_t len,
> soff_lo = to & (priv->asize - 1);
> eoff_lo = end & (priv->asize - 1);
>
> - pmc551_point(mtd, to, len, retlen, &ptr);
> + pmc551_point(mtd, to, len, retlen, (void **)&ptr, NULL);
>
> if (soff_hi == eoff_hi) {
> /* The whole thing fits within one access, so just one shot
> @@ -329,7 +335,8 @@ static int pmc551_write(struct mtd_info *mtd,
> loff_t to, size_t len,
> goto out;
> }
> soff_hi += priv->asize;
> - pmc551_point(mtd, soff_hi, priv->asize, retlen, &ptr);
> + pmc551_point(mtd, soff_hi, priv->asize, retlen,
> + (void **)&ptr, NULL);
> }
> memcpy(ptr, copyfrom, eoff_lo);
> copyfrom += eoff_lo;
> diff --git a/drivers/mtd/devices/slram.c b/drivers/mtd/devices/slram.c
> index d293add..cb86db7 100644
> --- a/drivers/mtd/devices/slram.c
> +++ b/drivers/mtd/devices/slram.c
> @@ -76,8 +76,9 @@ static char *map;
> static slram_mtd_list_t *slram_mtdlist = NULL;
>
> static int slram_erase(struct mtd_info *, struct erase_info *);
> -static int slram_point(struct mtd_info *, loff_t, size_t, size_t *, u_char **);
> -static void slram_unpoint(struct mtd_info *, u_char *, loff_t, size_t);
> +static int slram_point(struct mtd_info *, loff_t, size_t, size_t *, void **,
> + resource_size_t *);
> +static void slram_unpoint(struct mtd_info *, loff_t, size_t);
> static int slram_read(struct mtd_info *, loff_t, size_t, size_t *, u_char *);
> static int slram_write(struct mtd_info *, loff_t, size_t, size_t *,
> const u_char *);
>
> @@ -104,19 +105,23 @@ static int slram_erase(struct mtd_info *mtd,
> struct erase_info *instr)
> }
>
> static int slram_point(struct mtd_info *mtd, loff_t from, size_t len,
> - size_t *retlen, u_char **mtdbuf)
> + size_t *retlen, void **virt, resource_size_t *phys)
> {
> slram_priv_t *priv = mtd->priv;
>
> + /* can we return a physical address with this driver? */
> + if (phys)
> + return -EINVAL;
> +
> if (from + len > mtd->size)
> return -EINVAL;
>
> - *mtdbuf = priv->start + from;
> + *virt = priv->start + from;
> *retlen = len;
> return(0);
> }
>
> -static void slram_unpoint(struct mtd_info *mtd, u_char *addr, loff_t
> from, size_t len)
> +static void slram_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
> {
> }
>
> diff --git a/drivers/mtd/maps/uclinux.c b/drivers/mtd/maps/uclinux.c
> index 14ffb1a..c42f4b8 100644
> --- a/drivers/mtd/maps/uclinux.c
> +++ b/drivers/mtd/maps/uclinux.c
> @@ -40,10 +40,12 @@ struct mtd_partition uclinux_romfs[] = {
> /****************************************************************************/
>
> int uclinux_point(struct mtd_info *mtd, loff_t from, size_t len,
> - size_t *retlen, u_char **mtdbuf)
> + size_t *retlen, void **virt, resource_size_t *phys)
> {
> struct map_info *map = mtd->priv;
> - *mtdbuf = (u_char *) (map->virt + ((int) from));
> + *virt = map->virt + from;
> + if (phys)
> + *phys = map->phys + from;
> *retlen = len;
> return(0);
> }
> diff --git a/drivers/mtd/mtdpart.c b/drivers/mtd/mtdpart.c
> index c66902d..07c7011 100644
> --- a/drivers/mtd/mtdpart.c
> +++ b/drivers/mtd/mtdpart.c
> @@ -68,7 +68,7 @@ static int part_read (struct mtd_info *mtd, loff_t
> from, size_t len,
> }
>
> static int part_point (struct mtd_info *mtd, loff_t from, size_t len,
> - size_t *retlen, u_char **buf)
> + size_t *retlen, void **virt, resource_size_t *phys)
> {
> struct mtd_part *part = PART(mtd);
> if (from >= mtd->size)
> @@ -76,14 +76,14 @@ static int part_point (struct mtd_info *mtd,
> loff_t from, size_t len,
> else if (from + len > mtd->size)
> len = mtd->size - from;
> return part->master->point (part->master, from + part->offset,
> - len, retlen, buf);
> + len, retlen, virt, phys);
> }
>
> -static void part_unpoint (struct mtd_info *mtd, u_char *addr, loff_t
> from, size_t len)
> +static void part_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
> {
> struct mtd_part *part = PART(mtd);
>
> - part->master->unpoint (part->master, addr, from + part->offset, len);
> + part->master->unpoint(part->master, from + part->offset, len);
> }
>
> static int part_read_oob(struct mtd_info *mtd, loff_t from,
> diff --git a/fs/jffs2/erase.c b/fs/jffs2/erase.c
> index a1db918..6c2a046 100644
> --- a/fs/jffs2/erase.c
> +++ b/fs/jffs2/erase.c
> @@ -332,7 +332,8 @@ static int jffs2_block_check_erase(struct
> jffs2_sb_info *c, struct jffs2_erasebl
> if (c->mtd->point) {
> unsigned long *wordebuf;
>
> - ret = c->mtd->point(c->mtd, jeb->offset, c->sector_size, &retlen,
> (unsigned char **)&ebuf);
> + ret = c->mtd->point(c->mtd, jeb->offset, c->sector_size,
> + &retlen, &ebuf, NULL);
> if (ret) {
> D1(printk(KERN_DEBUG "MTD point failed %d\n", ret));
> goto do_flash_read;
> @@ -340,7 +341,7 @@ static int jffs2_block_check_erase(struct
> jffs2_sb_info *c, struct jffs2_erasebl
> if (retlen < c->sector_size) {
> /* Don't muck about if it won't let us point to the whole erase sector */
> D1(printk(KERN_DEBUG "MTD point returned len too short: 0x%zx\n", retlen));
> - c->mtd->unpoint(c->mtd, ebuf, jeb->offset, retlen);
> + c->mtd->unpoint(c->mtd, jeb->offset, retlen);
> goto do_flash_read;
> }
> wordebuf = ebuf-sizeof(*wordebuf);
> @@ -349,7 +350,7 @@ static int jffs2_block_check_erase(struct
> jffs2_sb_info *c, struct jffs2_erasebl
> if (*++wordebuf != ~0)
> break;
> } while(--retlen);
> - c->mtd->unpoint(c->mtd, ebuf, jeb->offset, c->sector_size);
> + c->mtd->unpoint(c->mtd, jeb->offset, c->sector_size);
> if (retlen)
> printk(KERN_WARNING "Newly-erased block contained word 0x%lx at
> offset 0x%08tx\n",
> *wordebuf, jeb->offset + c->sector_size-retlen*sizeof(*wordebuf));
> diff --git a/fs/jffs2/readinode.c b/fs/jffs2/readinode.c
> index e512a93..22acc12 100644
> --- a/fs/jffs2/readinode.c
> +++ b/fs/jffs2/readinode.c
> @@ -63,10 +63,11 @@ static int check_node_data(struct jffs2_sb_info
> *c, struct jffs2_tmp_dnode_info
> /* TODO: instead, incapsulate point() stuff to jffs2_flash_read(),
> * adding and jffs2_flash_read_end() interface. */
> if (c->mtd->point) {
> - err = c->mtd->point(c->mtd, ofs, len, &retlen, &buffer);
> + err = c->mtd->point(c->mtd, ofs, len, &retlen,
> + (void **)&buffer, NULL);
> if (!err && retlen < len) {
> JFFS2_WARNING("MTD point returned len too short: %zu instead of
> %u.\n", retlen, tn->csize);
> - c->mtd->unpoint(c->mtd, buffer, ofs, retlen);
> + c->mtd->unpoint(c->mtd, ofs, retlen);
> } else if (err)
> JFFS2_WARNING("MTD point failed: error code %d.\n", err);
> else
> @@ -100,7 +101,7 @@ static int check_node_data(struct jffs2_sb_info
> *c, struct jffs2_tmp_dnode_info
> kfree(buffer);
> #ifndef __ECOS
> else
> - c->mtd->unpoint(c->mtd, buffer, ofs, len);
> + c->mtd->unpoint(c->mtd, ofs, len);
> #endif
>
> if (crc != tn->data_crc) {
> @@ -136,7 +137,7 @@ free_out:
> kfree(buffer);
> #ifndef __ECOS
> else
> - c->mtd->unpoint(c->mtd, buffer, ofs, len);
> + c->mtd->unpoint(c->mtd, ofs, len);
> #endif
> return err;
> }
> diff --git a/fs/jffs2/scan.c b/fs/jffs2/scan.c
> index 272872d..b1b3884 100644
> --- a/fs/jffs2/scan.c
> +++ b/fs/jffs2/scan.c
> @@ -97,11 +97,12 @@ int jffs2_scan_medium(struct jffs2_sb_info *c)
> size_t pointlen;
>
> if (c->mtd->point) {
> - ret = c->mtd->point (c->mtd, 0, c->mtd->size, &pointlen, &flashbuf);
> + ret = c->mtd->point(c->mtd, 0, c->mtd->size, &pointlen,
> + (void **)&flashbuf, NULL);
> if (!ret && pointlen < c->mtd->size) {
> /* Don't muck about if it won't let us point to the whole flash */
> D1(printk(KERN_DEBUG "MTD point returned len too short: 0x%zx\n",
> pointlen));
> - c->mtd->unpoint(c->mtd, flashbuf, 0, pointlen);
> + c->mtd->unpoint(c->mtd, 0, pointlen);
> flashbuf = NULL;
> }
> if (ret)
> @@ -267,7 +268,7 @@ int jffs2_scan_medium(struct jffs2_sb_info *c)
> kfree(flashbuf);
> #ifndef __ECOS
> else
> - c->mtd->unpoint(c->mtd, flashbuf, 0, c->mtd->size);
> + c->mtd->unpoint(c->mtd, 0, c->mtd->size);
> #endif
> if (s)
> kfree(s);
> diff --git a/include/linux/mtd/mtd.h b/include/linux/mtd/mtd.h
> index 0a13bb3..245f909 100644
> --- a/include/linux/mtd/mtd.h
> +++ b/include/linux/mtd/mtd.h
> @@ -143,10 +143,12 @@ struct mtd_info {
> int (*erase) (struct mtd_info *mtd, struct erase_info *instr);
>
> /* This stuff for eXecute-In-Place */
> - int (*point) (struct mtd_info *mtd, loff_t from, size_t len, size_t
> *retlen, u_char **mtdbuf);
> + /* phys is optional and may be set to NULL */
> + int (*point) (struct mtd_info *mtd, loff_t from, size_t len,
> + size_t *retlen, void **virt, resource_size_t *phys);
>
> /* We probably shouldn't allow XIP if the unpoint isn't a NULL */
> - void (*unpoint) (struct mtd_info *mtd, u_char * addr, loff_t from,
> size_t len);
> + void (*unpoint) (struct mtd_info *mtd, loff_t from, size_t len);
>
>
> int (*read) (struct mtd_info *mtd, loff_t from, size_t len, size_t
> *retlen, u_char *buf);
> diff --git a/include/linux/mtd/pmc551.h b/include/linux/mtd/pmc551.h
> index a7f6d20..5cc070c 100644
> --- a/include/linux/mtd/pmc551.h
> +++ b/include/linux/mtd/pmc551.h
> @@ -36,8 +36,9 @@ struct mypriv {
> * Function Prototypes
> */
> static int pmc551_erase(struct mtd_info *, struct erase_info *);
> -static void pmc551_unpoint(struct mtd_info *, u_char *, loff_t, size_t);
> -static int pmc551_point (struct mtd_info *mtd, loff_t from, size_t
> len, size_t *retlen, u_char **mtdbuf);
> +static void pmc551_unpoint(struct mtd_info *, loff_t, size_t);
> +static int pmc551_point(struct mtd_info *mtd, loff_t from, size_t len,
> + size_t *retlen, void **virt, resource_size_t *phys);
> static int pmc551_read(struct mtd_info *, loff_t, size_t, size_t *, u_char *);
> static int pmc551_write(struct mtd_info *, loff_t, size_t, size_t *,
> const u_char *);
>
> ______________________________________________________
> Linux MTD discussion mailing list
> http://lists.infradead.org/mailman/listinfo/linux-mtd/
Jörn
--
It does not require a majority to prevail, but rather an irate,
tireless minority keen to set brush fires in people's minds.
-- Samuel Adams
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