mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-11 21:38:32 +08:00
mtd: add mtd_ooblayout_xxx() helper functions
In order to make the ecclayout definition completely dynamic we need to rework the way the OOB layout are defined and iterated. Create a few mtd_ooblayout_xxx() helpers to ease OOB bytes manipulation and hide ecclayout internals to their users. Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
This commit is contained in:
Boris Brezillon
parent
c4f3ef2c6c
commit
75eb2cec25
@ -1016,6 +1016,406 @@ int mtd_write_oob(struct mtd_info *mtd, loff_t to,
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(mtd_write_oob);
|
||||
|
||||
/**
|
||||
* mtd_ooblayout_ecc - Get the OOB region definition of a specific ECC section
|
||||
* @mtd: MTD device structure
|
||||
* @section: ECC section. Depending on the layout you may have all the ECC
|
||||
* bytes stored in a single contiguous section, or one section
|
||||
* per ECC chunk (and sometime several sections for a single ECC
|
||||
* ECC chunk)
|
||||
* @oobecc: OOB region struct filled with the appropriate ECC position
|
||||
* information
|
||||
*
|
||||
* This functions return ECC section information in the OOB area. I you want
|
||||
* to get all the ECC bytes information, then you should call
|
||||
* mtd_ooblayout_ecc(mtd, section++, oobecc) until it returns -ERANGE.
|
||||
*
|
||||
* Returns zero on success, a negative error code otherwise.
|
||||
*/
|
||||
int mtd_ooblayout_ecc(struct mtd_info *mtd, int section,
|
||||
struct mtd_oob_region *oobecc)
|
||||
{
|
||||
int eccbyte = 0, cursection = 0, length = 0, eccpos = 0;
|
||||
|
||||
memset(oobecc, 0, sizeof(*oobecc));
|
||||
|
||||
if (!mtd || section < 0)
|
||||
return -EINVAL;
|
||||
|
||||
if (!mtd->ecclayout)
|
||||
return -ENOTSUPP;
|
||||
|
||||
/*
|
||||
* This logic allows us to reuse the ->ecclayout information and
|
||||
* expose them as ECC regions (as done for the OOB free regions).
|
||||
*
|
||||
* TODO: this should be dropped as soon as we get rid of the
|
||||
* ->ecclayout field.
|
||||
*/
|
||||
for (eccbyte = 0; eccbyte < mtd->ecclayout->eccbytes; eccbyte++) {
|
||||
eccpos = mtd->ecclayout->eccpos[eccbyte];
|
||||
|
||||
if (eccbyte < mtd->ecclayout->eccbytes - 1) {
|
||||
int neccpos = mtd->ecclayout->eccpos[eccbyte + 1];
|
||||
|
||||
if (eccpos + 1 == neccpos) {
|
||||
length++;
|
||||
continue;
|
||||
}
|
||||
}
|
||||
|
||||
if (section == cursection)
|
||||
break;
|
||||
|
||||
length = 0;
|
||||
cursection++;
|
||||
}
|
||||
|
||||
if (cursection != section || eccbyte >= mtd->ecclayout->eccbytes)
|
||||
return -ERANGE;
|
||||
|
||||
oobecc->length = length + 1;
|
||||
oobecc->offset = eccpos - length;
|
||||
|
||||
return 0;
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(mtd_ooblayout_ecc);
|
||||
|
||||
/**
|
||||
* mtd_ooblayout_free - Get the OOB region definition of a specific free
|
||||
* section
|
||||
* @mtd: MTD device structure
|
||||
* @section: Free section you are interested in. Depending on the layout
|
||||
* you may have all the free bytes stored in a single contiguous
|
||||
* section, or one section per ECC chunk plus an extra section
|
||||
* for the remaining bytes (or other funky layout).
|
||||
* @oobfree: OOB region struct filled with the appropriate free position
|
||||
* information
|
||||
*
|
||||
* This functions return free bytes position in the OOB area. I you want
|
||||
* to get all the free bytes information, then you should call
|
||||
* mtd_ooblayout_free(mtd, section++, oobfree) until it returns -ERANGE.
|
||||
*
|
||||
* Returns zero on success, a negative error code otherwise.
|
||||
*/
|
||||
int mtd_ooblayout_free(struct mtd_info *mtd, int section,
|
||||
struct mtd_oob_region *oobfree)
|
||||
{
|
||||
memset(oobfree, 0, sizeof(*oobfree));
|
||||
|
||||
if (!mtd || section < 0)
|
||||
return -EINVAL;
|
||||
|
||||
if (!mtd->ecclayout)
|
||||
return -ENOTSUPP;
|
||||
|
||||
if (section >= MTD_MAX_OOBFREE_ENTRIES_LARGE)
|
||||
return -ERANGE;
|
||||
|
||||
oobfree->offset = mtd->ecclayout->oobfree[section].offset;
|
||||
oobfree->length = mtd->ecclayout->oobfree[section].length;
|
||||
|
||||
return 0;
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(mtd_ooblayout_free);
|
||||
|
||||
/**
|
||||
* mtd_ooblayout_find_region - Find the region attached to a specific byte
|
||||
* @mtd: mtd info structure
|
||||
* @byte: the byte we are searching for
|
||||
* @sectionp: pointer where the section id will be stored
|
||||
* @oobregion: used to retrieve the ECC position
|
||||
* @iter: iterator function. Should be either mtd_ooblayout_free or
|
||||
* mtd_ooblayout_ecc depending on the region type you're searching for
|
||||
*
|
||||
* This functions returns the section id and oobregion information of a
|
||||
* specific byte. For example, say you want to know where the 4th ECC byte is
|
||||
* stored, you'll use:
|
||||
*
|
||||
* mtd_ooblayout_find_region(mtd, 3, §ion, &oobregion, mtd_ooblayout_ecc);
|
||||
*
|
||||
* Returns zero on success, a negative error code otherwise.
|
||||
*/
|
||||
static int mtd_ooblayout_find_region(struct mtd_info *mtd, int byte,
|
||||
int *sectionp, struct mtd_oob_region *oobregion,
|
||||
int (*iter)(struct mtd_info *,
|
||||
int section,
|
||||
struct mtd_oob_region *oobregion))
|
||||
{
|
||||
int pos = 0, ret, section = 0;
|
||||
|
||||
memset(oobregion, 0, sizeof(*oobregion));
|
||||
|
||||
while (1) {
|
||||
ret = iter(mtd, section, oobregion);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
if (pos + oobregion->length > byte)
|
||||
break;
|
||||
|
||||
pos += oobregion->length;
|
||||
section++;
|
||||
}
|
||||
|
||||
/*
|
||||
* Adjust region info to make it start at the beginning at the
|
||||
* 'start' ECC byte.
|
||||
*/
|
||||
oobregion->offset += byte - pos;
|
||||
oobregion->length -= byte - pos;
|
||||
*sectionp = section;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/**
|
||||
* mtd_ooblayout_find_eccregion - Find the ECC region attached to a specific
|
||||
* ECC byte
|
||||
* @mtd: mtd info structure
|
||||
* @eccbyte: the byte we are searching for
|
||||
* @sectionp: pointer where the section id will be stored
|
||||
* @oobregion: OOB region information
|
||||
*
|
||||
* Works like mtd_ooblayout_find_region() except it searches for a specific ECC
|
||||
* byte.
|
||||
*
|
||||
* Returns zero on success, a negative error code otherwise.
|
||||
*/
|
||||
int mtd_ooblayout_find_eccregion(struct mtd_info *mtd, int eccbyte,
|
||||
int *section,
|
||||
struct mtd_oob_region *oobregion)
|
||||
{
|
||||
return mtd_ooblayout_find_region(mtd, eccbyte, section, oobregion,
|
||||
mtd_ooblayout_ecc);
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(mtd_ooblayout_find_eccregion);
|
||||
|
||||
/**
|
||||
* mtd_ooblayout_get_bytes - Extract OOB bytes from the oob buffer
|
||||
* @mtd: mtd info structure
|
||||
* @buf: destination buffer to store OOB bytes
|
||||
* @oobbuf: OOB buffer
|
||||
* @start: first byte to retrieve
|
||||
* @nbytes: number of bytes to retrieve
|
||||
* @iter: section iterator
|
||||
*
|
||||
* Extract bytes attached to a specific category (ECC or free)
|
||||
* from the OOB buffer and copy them into buf.
|
||||
*
|
||||
* Returns zero on success, a negative error code otherwise.
|
||||
*/
|
||||
static int mtd_ooblayout_get_bytes(struct mtd_info *mtd, u8 *buf,
|
||||
const u8 *oobbuf, int start, int nbytes,
|
||||
int (*iter)(struct mtd_info *,
|
||||
int section,
|
||||
struct mtd_oob_region *oobregion))
|
||||
{
|
||||
struct mtd_oob_region oobregion = { };
|
||||
int section = 0, ret;
|
||||
|
||||
ret = mtd_ooblayout_find_region(mtd, start, §ion,
|
||||
&oobregion, iter);
|
||||
|
||||
while (!ret) {
|
||||
int cnt;
|
||||
|
||||
cnt = oobregion.length > nbytes ? nbytes : oobregion.length;
|
||||
memcpy(buf, oobbuf + oobregion.offset, cnt);
|
||||
buf += cnt;
|
||||
nbytes -= cnt;
|
||||
|
||||
if (!nbytes)
|
||||
break;
|
||||
|
||||
ret = iter(mtd, ++section, &oobregion);
|
||||
}
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
/**
|
||||
* mtd_ooblayout_set_bytes - put OOB bytes into the oob buffer
|
||||
* @mtd: mtd info structure
|
||||
* @buf: source buffer to get OOB bytes from
|
||||
* @oobbuf: OOB buffer
|
||||
* @start: first OOB byte to set
|
||||
* @nbytes: number of OOB bytes to set
|
||||
* @iter: section iterator
|
||||
*
|
||||
* Fill the OOB buffer with data provided in buf. The category (ECC or free)
|
||||
* is selected by passing the appropriate iterator.
|
||||
*
|
||||
* Returns zero on success, a negative error code otherwise.
|
||||
*/
|
||||
static int mtd_ooblayout_set_bytes(struct mtd_info *mtd, const u8 *buf,
|
||||
u8 *oobbuf, int start, int nbytes,
|
||||
int (*iter)(struct mtd_info *,
|
||||
int section,
|
||||
struct mtd_oob_region *oobregion))
|
||||
{
|
||||
struct mtd_oob_region oobregion = { };
|
||||
int section = 0, ret;
|
||||
|
||||
ret = mtd_ooblayout_find_region(mtd, start, §ion,
|
||||
&oobregion, iter);
|
||||
|
||||
while (!ret) {
|
||||
int cnt;
|
||||
|
||||
cnt = oobregion.length > nbytes ? nbytes : oobregion.length;
|
||||
memcpy(oobbuf + oobregion.offset, buf, cnt);
|
||||
buf += cnt;
|
||||
nbytes -= cnt;
|
||||
|
||||
if (!nbytes)
|
||||
break;
|
||||
|
||||
ret = iter(mtd, ++section, &oobregion);
|
||||
}
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
/**
|
||||
* mtd_ooblayout_count_bytes - count the number of bytes in a OOB category
|
||||
* @mtd: mtd info structure
|
||||
* @iter: category iterator
|
||||
*
|
||||
* Count the number of bytes in a given category.
|
||||
*
|
||||
* Returns a positive value on success, a negative error code otherwise.
|
||||
*/
|
||||
static int mtd_ooblayout_count_bytes(struct mtd_info *mtd,
|
||||
int (*iter)(struct mtd_info *,
|
||||
int section,
|
||||
struct mtd_oob_region *oobregion))
|
||||
{
|
||||
struct mtd_oob_region oobregion = { };
|
||||
int section = 0, ret, nbytes = 0;
|
||||
|
||||
while (1) {
|
||||
ret = iter(mtd, section++, &oobregion);
|
||||
if (ret) {
|
||||
if (ret == -ERANGE)
|
||||
ret = nbytes;
|
||||
break;
|
||||
}
|
||||
|
||||
nbytes += oobregion.length;
|
||||
}
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
/**
|
||||
* mtd_ooblayout_get_eccbytes - extract ECC bytes from the oob buffer
|
||||
* @mtd: mtd info structure
|
||||
* @eccbuf: destination buffer to store ECC bytes
|
||||
* @oobbuf: OOB buffer
|
||||
* @start: first ECC byte to retrieve
|
||||
* @nbytes: number of ECC bytes to retrieve
|
||||
*
|
||||
* Works like mtd_ooblayout_get_bytes(), except it acts on ECC bytes.
|
||||
*
|
||||
* Returns zero on success, a negative error code otherwise.
|
||||
*/
|
||||
int mtd_ooblayout_get_eccbytes(struct mtd_info *mtd, u8 *eccbuf,
|
||||
const u8 *oobbuf, int start, int nbytes)
|
||||
{
|
||||
return mtd_ooblayout_get_bytes(mtd, eccbuf, oobbuf, start, nbytes,
|
||||
mtd_ooblayout_ecc);
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(mtd_ooblayout_get_eccbytes);
|
||||
|
||||
/**
|
||||
* mtd_ooblayout_set_eccbytes - set ECC bytes into the oob buffer
|
||||
* @mtd: mtd info structure
|
||||
* @eccbuf: source buffer to get ECC bytes from
|
||||
* @oobbuf: OOB buffer
|
||||
* @start: first ECC byte to set
|
||||
* @nbytes: number of ECC bytes to set
|
||||
*
|
||||
* Works like mtd_ooblayout_set_bytes(), except it acts on ECC bytes.
|
||||
*
|
||||
* Returns zero on success, a negative error code otherwise.
|
||||
*/
|
||||
int mtd_ooblayout_set_eccbytes(struct mtd_info *mtd, const u8 *eccbuf,
|
||||
u8 *oobbuf, int start, int nbytes)
|
||||
{
|
||||
return mtd_ooblayout_set_bytes(mtd, eccbuf, oobbuf, start, nbytes,
|
||||
mtd_ooblayout_ecc);
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(mtd_ooblayout_set_eccbytes);
|
||||
|
||||
/**
|
||||
* mtd_ooblayout_get_databytes - extract data bytes from the oob buffer
|
||||
* @mtd: mtd info structure
|
||||
* @databuf: destination buffer to store ECC bytes
|
||||
* @oobbuf: OOB buffer
|
||||
* @start: first ECC byte to retrieve
|
||||
* @nbytes: number of ECC bytes to retrieve
|
||||
*
|
||||
* Works like mtd_ooblayout_get_bytes(), except it acts on free bytes.
|
||||
*
|
||||
* Returns zero on success, a negative error code otherwise.
|
||||
*/
|
||||
int mtd_ooblayout_get_databytes(struct mtd_info *mtd, u8 *databuf,
|
||||
const u8 *oobbuf, int start, int nbytes)
|
||||
{
|
||||
return mtd_ooblayout_get_bytes(mtd, databuf, oobbuf, start, nbytes,
|
||||
mtd_ooblayout_free);
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(mtd_ooblayout_get_databytes);
|
||||
|
||||
/**
|
||||
* mtd_ooblayout_get_eccbytes - set data bytes into the oob buffer
|
||||
* @mtd: mtd info structure
|
||||
* @eccbuf: source buffer to get data bytes from
|
||||
* @oobbuf: OOB buffer
|
||||
* @start: first ECC byte to set
|
||||
* @nbytes: number of ECC bytes to set
|
||||
*
|
||||
* Works like mtd_ooblayout_get_bytes(), except it acts on free bytes.
|
||||
*
|
||||
* Returns zero on success, a negative error code otherwise.
|
||||
*/
|
||||
int mtd_ooblayout_set_databytes(struct mtd_info *mtd, const u8 *databuf,
|
||||
u8 *oobbuf, int start, int nbytes)
|
||||
{
|
||||
return mtd_ooblayout_set_bytes(mtd, databuf, oobbuf, start, nbytes,
|
||||
mtd_ooblayout_free);
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(mtd_ooblayout_set_databytes);
|
||||
|
||||
/**
|
||||
* mtd_ooblayout_count_freebytes - count the number of free bytes in OOB
|
||||
* @mtd: mtd info structure
|
||||
*
|
||||
* Works like mtd_ooblayout_count_bytes(), except it count free bytes.
|
||||
*
|
||||
* Returns zero on success, a negative error code otherwise.
|
||||
*/
|
||||
int mtd_ooblayout_count_freebytes(struct mtd_info *mtd)
|
||||
{
|
||||
return mtd_ooblayout_count_bytes(mtd, mtd_ooblayout_free);
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(mtd_ooblayout_count_freebytes);
|
||||
|
||||
/**
|
||||
* mtd_ooblayout_count_freebytes - count the number of ECC bytes in OOB
|
||||
* @mtd: mtd info structure
|
||||
*
|
||||
* Works like mtd_ooblayout_count_bytes(), except it count ECC bytes.
|
||||
*
|
||||
* Returns zero on success, a negative error code otherwise.
|
||||
*/
|
||||
int mtd_ooblayout_count_eccbytes(struct mtd_info *mtd)
|
||||
{
|
||||
return mtd_ooblayout_count_bytes(mtd, mtd_ooblayout_ecc);
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(mtd_ooblayout_count_eccbytes);
|
||||
|
||||
/*
|
||||
* Method to access the protection register area, present in some flash
|
||||
* devices. The user data is one time programmable but the factory data is read
|
||||
|
||||
@ -108,6 +108,21 @@ struct nand_ecclayout {
|
||||
struct nand_oobfree oobfree[MTD_MAX_OOBFREE_ENTRIES_LARGE];
|
||||
};
|
||||
|
||||
/**
|
||||
* struct mtd_oob_region - oob region definition
|
||||
* @offset: region offset
|
||||
* @length: region length
|
||||
*
|
||||
* This structure describes a region of the OOB area, and is used
|
||||
* to retrieve ECC or free bytes sections.
|
||||
* Each section is defined by an offset within the OOB area and a
|
||||
* length.
|
||||
*/
|
||||
struct mtd_oob_region {
|
||||
u32 offset;
|
||||
u32 length;
|
||||
};
|
||||
|
||||
struct module; /* only needed for owner field in mtd_info */
|
||||
|
||||
struct mtd_info {
|
||||
@ -253,6 +268,24 @@ struct mtd_info {
|
||||
int usecount;
|
||||
};
|
||||
|
||||
int mtd_ooblayout_ecc(struct mtd_info *mtd, int section,
|
||||
struct mtd_oob_region *oobecc);
|
||||
int mtd_ooblayout_find_eccregion(struct mtd_info *mtd, int eccbyte,
|
||||
int *section,
|
||||
struct mtd_oob_region *oobregion);
|
||||
int mtd_ooblayout_get_eccbytes(struct mtd_info *mtd, u8 *eccbuf,
|
||||
const u8 *oobbuf, int start, int nbytes);
|
||||
int mtd_ooblayout_set_eccbytes(struct mtd_info *mtd, const u8 *eccbuf,
|
||||
u8 *oobbuf, int start, int nbytes);
|
||||
int mtd_ooblayout_free(struct mtd_info *mtd, int section,
|
||||
struct mtd_oob_region *oobfree);
|
||||
int mtd_ooblayout_get_databytes(struct mtd_info *mtd, u8 *databuf,
|
||||
const u8 *oobbuf, int start, int nbytes);
|
||||
int mtd_ooblayout_set_databytes(struct mtd_info *mtd, const u8 *databuf,
|
||||
u8 *oobbuf, int start, int nbytes);
|
||||
int mtd_ooblayout_count_freebytes(struct mtd_info *mtd);
|
||||
int mtd_ooblayout_count_eccbytes(struct mtd_info *mtd);
|
||||
|
||||
static inline void mtd_set_of_node(struct mtd_info *mtd,
|
||||
struct device_node *np)
|
||||
{
|
||||
|
||||
Loading…
Reference in New Issue
Block a user