diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/packing.c | 293 | ||||
| -rw-r--r-- | lib/packing_test.c | 61 | ||||
| -rw-r--r-- | lib/win_minmax.c | 1 |
3 files changed, 289 insertions, 66 deletions
diff --git a/lib/packing.c b/lib/packing.c index 793942745e34..bb1643d9e64d 100644 --- a/lib/packing.c +++ b/lib/packing.c @@ -5,10 +5,37 @@ #include <linux/packing.h> #include <linux/module.h> #include <linux/bitops.h> +#include <linux/bits.h> #include <linux/errno.h> #include <linux/types.h> #include <linux/bitrev.h> +#define __pack_fields(pbuf, pbuflen, ustruct, fields, num_fields, quirks) \ + ({ \ + for (size_t i = 0; i < (num_fields); i++) { \ + typeof(&(fields)[0]) field = &(fields)[i]; \ + u64 uval; \ + \ + uval = ustruct_field_to_u64(ustruct, field->offset, field->size); \ + \ + __pack(pbuf, uval, field->startbit, field->endbit, \ + pbuflen, quirks); \ + } \ + }) + +#define __unpack_fields(pbuf, pbuflen, ustruct, fields, num_fields, quirks) \ + ({ \ + for (size_t i = 0; i < (num_fields); i++) { \ + typeof(&(fields)[0]) field = &fields[i]; \ + u64 uval; \ + \ + __unpack(pbuf, &uval, field->startbit, field->endbit, \ + pbuflen, quirks); \ + \ + u64_to_ustruct_field(ustruct, field->offset, field->size, uval); \ + } \ + }) + /** * calculate_box_addr - Determine physical location of byte in buffer * @box: Index of byte within buffer seen as a logical big-endian big number @@ -51,64 +78,29 @@ static size_t calculate_box_addr(size_t box, size_t len, u8 quirks) return offset_of_group + offset_in_group; } -/** - * pack - Pack u64 number into bitfield of buffer. - * - * @pbuf: Pointer to a buffer holding the packed value. - * @uval: CPU-readable unpacked value to pack. - * @startbit: The index (in logical notation, compensated for quirks) where - * the packed value starts within pbuf. Must be larger than, or - * equal to, endbit. - * @endbit: The index (in logical notation, compensated for quirks) where - * the packed value ends within pbuf. Must be smaller than, or equal - * to, startbit. - * @pbuflen: The length in bytes of the packed buffer pointed to by @pbuf. - * @quirks: A bit mask of QUIRK_LITTLE_ENDIAN, QUIRK_LSW32_IS_FIRST and - * QUIRK_MSB_ON_THE_RIGHT. - * - * Return: 0 on success, EINVAL or ERANGE if called incorrectly. Assuming - * correct usage, return code may be discarded. The @pbuf memory will - * be modified on success. - */ -int pack(void *pbuf, u64 uval, size_t startbit, size_t endbit, size_t pbuflen, - u8 quirks) +static void __pack(void *pbuf, u64 uval, size_t startbit, size_t endbit, + size_t pbuflen, u8 quirks) { /* Logical byte indices corresponding to the * start and end of the field. */ - int plogical_first_u8, plogical_last_u8, box; - /* width of the field to access in the pbuf */ - u64 value_width; - - /* startbit is expected to be larger than endbit, and both are - * expected to be within the logically addressable range of the buffer. - */ - if (unlikely(startbit < endbit || startbit >= BITS_PER_BYTE * pbuflen)) - /* Invalid function call */ - return -EINVAL; - - value_width = startbit - endbit + 1; - if (unlikely(value_width > 64)) - return -ERANGE; + int plogical_first_u8 = startbit / BITS_PER_BYTE; + int plogical_last_u8 = endbit / BITS_PER_BYTE; + int value_width = startbit - endbit + 1; + int box; /* Check if "uval" fits in "value_width" bits. - * If value_width is 64, the check will fail, but any - * 64-bit uval will surely fit. + * The test only works for value_width < 64, but in the latter case, + * any 64-bit uval will surely fit. */ - if (unlikely(value_width < 64 && uval >= (1ull << value_width))) - /* Cannot store "uval" inside "value_width" bits. - * Truncating "uval" is most certainly not desirable, - * so simply erroring out is appropriate. - */ - return -ERANGE; + WARN(value_width < 64 && uval >= (1ull << value_width), + "Cannot store 0x%llx inside bits %zu-%zu - will truncate\n", + uval, startbit, endbit); /* Iterate through an idealistic view of the pbuf as an u64 with * no quirks, u8 by u8 (aligned at u8 boundaries), from high to low * logical bit significance. "box" denotes the current logical u8. */ - plogical_first_u8 = startbit / BITS_PER_BYTE; - plogical_last_u8 = endbit / BITS_PER_BYTE; - for (box = plogical_first_u8; box >= plogical_last_u8; box--) { /* Bit indices into the currently accessed 8-bit box */ size_t box_start_bit, box_end_bit, box_addr; @@ -163,15 +155,13 @@ int pack(void *pbuf, u64 uval, size_t startbit, size_t endbit, size_t pbuflen, ((u8 *)pbuf)[box_addr] &= ~box_mask; ((u8 *)pbuf)[box_addr] |= pval; } - return 0; } -EXPORT_SYMBOL(pack); /** - * unpack - Unpack u64 number from packed buffer. + * pack - Pack u64 number into bitfield of buffer. * * @pbuf: Pointer to a buffer holding the packed value. - * @uval: Pointer to an u64 holding the unpacked value. + * @uval: CPU-readable unpacked value to pack. * @startbit: The index (in logical notation, compensated for quirks) where * the packed value starts within pbuf. Must be larger than, or * equal to, endbit. @@ -183,19 +173,12 @@ EXPORT_SYMBOL(pack); * QUIRK_MSB_ON_THE_RIGHT. * * Return: 0 on success, EINVAL or ERANGE if called incorrectly. Assuming - * correct usage, return code may be discarded. The @uval will be - * modified on success. + * correct usage, return code may be discarded. The @pbuf memory will + * be modified on success. */ -int unpack(const void *pbuf, u64 *uval, size_t startbit, size_t endbit, - size_t pbuflen, u8 quirks) +int pack(void *pbuf, u64 uval, size_t startbit, size_t endbit, size_t pbuflen, + u8 quirks) { - /* Logical byte indices corresponding to the - * start and end of the field. - */ - int plogical_first_u8, plogical_last_u8, box; - /* width of the field to access in the pbuf */ - u64 value_width; - /* startbit is expected to be larger than endbit, and both are * expected to be within the logically addressable range of the buffer. */ @@ -203,10 +186,25 @@ int unpack(const void *pbuf, u64 *uval, size_t startbit, size_t endbit, /* Invalid function call */ return -EINVAL; - value_width = startbit - endbit + 1; - if (unlikely(value_width > 64)) + if (unlikely(startbit - endbit >= 64)) return -ERANGE; + __pack(pbuf, uval, startbit, endbit, pbuflen, quirks); + + return 0; +} +EXPORT_SYMBOL(pack); + +static void __unpack(const void *pbuf, u64 *uval, size_t startbit, size_t endbit, + size_t pbuflen, u8 quirks) +{ + /* Logical byte indices corresponding to the + * start and end of the field. + */ + int plogical_first_u8 = startbit / BITS_PER_BYTE; + int plogical_last_u8 = endbit / BITS_PER_BYTE; + int box; + /* Initialize parameter */ *uval = 0; @@ -214,9 +212,6 @@ int unpack(const void *pbuf, u64 *uval, size_t startbit, size_t endbit, * no quirks, u8 by u8 (aligned at u8 boundaries), from high to low * logical bit significance. "box" denotes the current logical u8. */ - plogical_first_u8 = startbit / BITS_PER_BYTE; - plogical_last_u8 = endbit / BITS_PER_BYTE; - for (box = plogical_first_u8; box >= plogical_last_u8; box--) { /* Bit indices into the currently accessed 8-bit box */ size_t box_start_bit, box_end_bit, box_addr; @@ -271,6 +266,46 @@ int unpack(const void *pbuf, u64 *uval, size_t startbit, size_t endbit, *uval &= ~proj_mask; *uval |= pval; } +} + +/** + * unpack - Unpack u64 number from packed buffer. + * + * @pbuf: Pointer to a buffer holding the packed value. + * @uval: Pointer to an u64 holding the unpacked value. + * @startbit: The index (in logical notation, compensated for quirks) where + * the packed value starts within pbuf. Must be larger than, or + * equal to, endbit. + * @endbit: The index (in logical notation, compensated for quirks) where + * the packed value ends within pbuf. Must be smaller than, or equal + * to, startbit. + * @pbuflen: The length in bytes of the packed buffer pointed to by @pbuf. + * @quirks: A bit mask of QUIRK_LITTLE_ENDIAN, QUIRK_LSW32_IS_FIRST and + * QUIRK_MSB_ON_THE_RIGHT. + * + * Return: 0 on success, EINVAL or ERANGE if called incorrectly. Assuming + * correct usage, return code may be discarded. The @uval will be + * modified on success. + */ +int unpack(const void *pbuf, u64 *uval, size_t startbit, size_t endbit, + size_t pbuflen, u8 quirks) +{ + /* width of the field to access in the pbuf */ + u64 value_width; + + /* startbit is expected to be larger than endbit, and both are + * expected to be within the logically addressable range of the buffer. + */ + if (startbit < endbit || startbit >= BITS_PER_BYTE * pbuflen) + /* Invalid function call */ + return -EINVAL; + + value_width = startbit - endbit + 1; + if (value_width > 64) + return -ERANGE; + + __unpack(pbuf, uval, startbit, endbit, pbuflen, quirks); + return 0; } EXPORT_SYMBOL(unpack); @@ -314,4 +349,130 @@ int packing(void *pbuf, u64 *uval, int startbit, int endbit, size_t pbuflen, } EXPORT_SYMBOL(packing); +static u64 ustruct_field_to_u64(const void *ustruct, size_t field_offset, + size_t field_size) +{ + switch (field_size) { + case 1: + return *((u8 *)(ustruct + field_offset)); + case 2: + return *((u16 *)(ustruct + field_offset)); + case 4: + return *((u32 *)(ustruct + field_offset)); + default: + return *((u64 *)(ustruct + field_offset)); + } +} + +static void u64_to_ustruct_field(void *ustruct, size_t field_offset, + size_t field_size, u64 uval) +{ + switch (field_size) { + case 1: + *((u8 *)(ustruct + field_offset)) = uval; + break; + case 2: + *((u16 *)(ustruct + field_offset)) = uval; + break; + case 4: + *((u32 *)(ustruct + field_offset)) = uval; + break; + default: + *((u64 *)(ustruct + field_offset)) = uval; + break; + } +} + +/** + * pack_fields_u8 - Pack array of fields + * + * @pbuf: Pointer to a buffer holding the packed value. + * @pbuflen: The length in bytes of the packed buffer pointed to by @pbuf. + * @ustruct: Pointer to CPU-readable structure holding the unpacked value. + * It is expected (but not checked) that this has the same data type + * as all struct packed_field_u8 definitions. + * @fields: Array of packed_field_u8 field definition. They must not overlap. + * @num_fields: Length of @fields array. + * @quirks: A bit mask of QUIRK_LITTLE_ENDIAN, QUIRK_LSW32_IS_FIRST and + * QUIRK_MSB_ON_THE_RIGHT. + * + * Use the pack_fields() macro instead of calling this directly. + */ +void pack_fields_u8(void *pbuf, size_t pbuflen, const void *ustruct, + const struct packed_field_u8 *fields, size_t num_fields, + u8 quirks) +{ + __pack_fields(pbuf, pbuflen, ustruct, fields, num_fields, quirks); +} +EXPORT_SYMBOL(pack_fields_u8); + +/** + * pack_fields_u16 - Pack array of fields + * + * @pbuf: Pointer to a buffer holding the packed value. + * @pbuflen: The length in bytes of the packed buffer pointed to by @pbuf. + * @ustruct: Pointer to CPU-readable structure holding the unpacked value. + * It is expected (but not checked) that this has the same data type + * as all struct packed_field_u16 definitions. + * @fields: Array of packed_field_u16 field definitions. They must not overlap. + * @num_fields: Length of @fields array. + * @quirks: A bit mask of QUIRK_LITTLE_ENDIAN, QUIRK_LSW32_IS_FIRST and + * QUIRK_MSB_ON_THE_RIGHT. + * + * Use the pack_fields() macro instead of calling this directly. + */ +void pack_fields_u16(void *pbuf, size_t pbuflen, const void *ustruct, + const struct packed_field_u16 *fields, size_t num_fields, + u8 quirks) +{ + __pack_fields(pbuf, pbuflen, ustruct, fields, num_fields, quirks); +} +EXPORT_SYMBOL(pack_fields_u16); + +/** + * unpack_fields_u8 - Unpack array of fields + * + * @pbuf: Pointer to a buffer holding the packed value. + * @pbuflen: The length in bytes of the packed buffer pointed to by @pbuf. + * @ustruct: Pointer to CPU-readable structure holding the unpacked value. + * It is expected (but not checked) that this has the same data type + * as all struct packed_field_u8 definitions. + * @fields: Array of packed_field_u8 field definitions. They must not overlap. + * @num_fields: Length of @fields array. + * @quirks: A bit mask of QUIRK_LITTLE_ENDIAN, QUIRK_LSW32_IS_FIRST and + * QUIRK_MSB_ON_THE_RIGHT. + * + * Use the unpack_fields() macro instead of calling this directly. + */ +void unpack_fields_u8(const void *pbuf, size_t pbuflen, void *ustruct, + const struct packed_field_u8 *fields, size_t num_fields, + u8 quirks) +{ + __unpack_fields(pbuf, pbuflen, ustruct, fields, num_fields, quirks); +} +EXPORT_SYMBOL(unpack_fields_u8); + +/** + * unpack_fields_u16 - Unpack array of fields + * + * @pbuf: Pointer to a buffer holding the packed value. + * @pbuflen: The length in bytes of the packed buffer pointed to by @pbuf. + * @ustruct: Pointer to CPU-readable structure holding the unpacked value. + * It is expected (but not checked) that this has the same data type + * as all struct packed_field_u16 definitions. + * @fields: Array of packed_field_u16 field definitions. They must not overlap. + * @num_fields: Length of @fields array. + * @quirks: A bit mask of QUIRK_LITTLE_ENDIAN, QUIRK_LSW32_IS_FIRST and + * QUIRK_MSB_ON_THE_RIGHT. + * + * Use the unpack_fields() macro instead of calling this directly. + */ +void unpack_fields_u16(const void *pbuf, size_t pbuflen, void *ustruct, + const struct packed_field_u16 *fields, size_t num_fields, + u8 quirks) +{ + __unpack_fields(pbuf, pbuflen, ustruct, fields, num_fields, quirks); +} +EXPORT_SYMBOL(unpack_fields_u16); + MODULE_DESCRIPTION("Generic bitfield packing and unpacking"); diff --git a/lib/packing_test.c b/lib/packing_test.c index b38ea43c03fd..ce3b83d33b04 100644 --- a/lib/packing_test.c +++ b/lib/packing_test.c @@ -396,9 +396,70 @@ static void packing_test_unpack(struct kunit *test) KUNIT_EXPECT_EQ(test, uval, params->uval); } +#define PACKED_BUF_SIZE 8 + +typedef struct __packed { u8 buf[PACKED_BUF_SIZE]; } packed_buf_t; + +struct test_data { + u32 field3; + u16 field2; + u16 field4; + u16 field6; + u8 field1; + u8 field5; +}; + +static const struct packed_field_u8 test_fields[] = { + PACKED_FIELD(63, 61, struct test_data, field1), + PACKED_FIELD(60, 52, struct test_data, field2), + PACKED_FIELD(51, 28, struct test_data, field3), + PACKED_FIELD(27, 14, struct test_data, field4), + PACKED_FIELD(13, 9, struct test_data, field5), + PACKED_FIELD(8, 0, struct test_data, field6), +}; + +static void packing_test_pack_fields(struct kunit *test) +{ + const struct test_data data = { + .field1 = 0x2, + .field2 = 0x100, + .field3 = 0xF00050, + .field4 = 0x7D3, + .field5 = 0x9, + .field6 = 0x10B, + }; + packed_buf_t expect = { + .buf = { 0x50, 0x0F, 0x00, 0x05, 0x01, 0xF4, 0xD3, 0x0B }, + }; + packed_buf_t buf = {}; + + pack_fields(&buf, sizeof(buf), &data, test_fields, 0); + + KUNIT_EXPECT_MEMEQ(test, &expect, &buf, sizeof(buf)); +} + +static void packing_test_unpack_fields(struct kunit *test) +{ + const packed_buf_t buf = { + .buf = { 0x17, 0x28, 0x10, 0x19, 0x3D, 0xA9, 0x07, 0x9C }, + }; + struct test_data data = {}; + + unpack_fields(&buf, sizeof(buf), &data, test_fields, 0); + + KUNIT_EXPECT_EQ(test, 0, data.field1); + KUNIT_EXPECT_EQ(test, 0x172, data.field2); + KUNIT_EXPECT_EQ(test, 0x810193, data.field3); + KUNIT_EXPECT_EQ(test, 0x36A4, data.field4); + KUNIT_EXPECT_EQ(test, 0x3, data.field5); + KUNIT_EXPECT_EQ(test, 0x19C, data.field6); +} + static struct kunit_case packing_test_cases[] = { KUNIT_CASE_PARAM(packing_test_pack, packing_gen_params), KUNIT_CASE_PARAM(packing_test_unpack, packing_gen_params), + KUNIT_CASE(packing_test_pack_fields), + KUNIT_CASE(packing_test_unpack_fields), {}, }; diff --git a/lib/win_minmax.c b/lib/win_minmax.c index ec10506834b6..1682e614309c 100644 --- a/lib/win_minmax.c +++ b/lib/win_minmax.c @@ -97,3 +97,4 @@ u32 minmax_running_min(struct minmax *m, u32 win, u32 t, u32 meas) return minmax_subwin_update(m, win, &val); } +EXPORT_SYMBOL(minmax_running_min); |