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Diffstat (limited to 'fs/ntfs3/lznt.c')
-rw-r--r--fs/ntfs3/lznt.c86
1 files changed, 43 insertions, 43 deletions
diff --git a/fs/ntfs3/lznt.c b/fs/ntfs3/lznt.c
index eb43b9f5149b..3acf0d9f0b15 100644
--- a/fs/ntfs3/lznt.c
+++ b/fs/ntfs3/lznt.c
@@ -4,6 +4,7 @@
* Copyright (C) 2019-2021 Paragon Software GmbH, All rights reserved.
*
*/
+
#include <linux/blkdev.h>
#include <linux/buffer_head.h>
#include <linux/fs.h>
@@ -14,7 +15,7 @@
#include "ntfs_fs.h"
// clang-format off
-/* src buffer is zero */
+/* Src buffer is zero. */
#define LZNT_ERROR_ALL_ZEROS 1
#define LZNT_CHUNK_SIZE 0x1000
// clang-format on
@@ -72,7 +73,7 @@ static size_t longest_match_std(const u8 *src, struct lznt *ctx)
hash[1] + 3, ctx->max_len - 3);
}
- /* Compare two matches and select the best one */
+ /* Compare two matches and select the best one. */
if (len1 < len2) {
ctx->best_match = hash[1];
len1 = len2;
@@ -129,10 +130,10 @@ static inline size_t parse_pair(u16 pair, size_t *offset, size_t index)
/*
* compress_chunk
*
- * returns one of the three values:
- * 0 - ok, 'cmpr' contains 'cmpr_chunk_size' bytes of compressed data
- * 1 - input buffer is full zero
- * -2 - the compressed buffer is too small to hold the compressed data
+ * Return:
+ * * 0 - Ok, @cmpr contains @cmpr_chunk_size bytes of compressed data.
+ * * 1 - Input buffer is full zero.
+ * * -2 - The compressed buffer is too small to hold the compressed data.
*/
static inline int compress_chunk(size_t (*match)(const u8 *, struct lznt *),
const u8 *unc, const u8 *unc_end, u8 *cmpr,
@@ -145,7 +146,7 @@ static inline int compress_chunk(size_t (*match)(const u8 *, struct lznt *),
u8 *cp = cmpr + 3;
u8 *cp2 = cmpr + 2;
u8 not_zero = 0;
- /* Control byte of 8-bit values: ( 0 - means byte as is, 1 - short pair ) */
+ /* Control byte of 8-bit values: ( 0 - means byte as is, 1 - short pair ). */
u8 ohdr = 0;
u8 *last;
u16 t16;
@@ -165,7 +166,7 @@ static inline int compress_chunk(size_t (*match)(const u8 *, struct lznt *),
while (unc + s_max_off[idx] < up)
ctx->max_len = s_max_len[++idx];
- // Find match
+ /* Find match. */
max_len = up + 3 <= unc_end ? (*match)(up, ctx) : 0;
if (!max_len) {
@@ -211,7 +212,7 @@ NotCompressed:
return -2;
/*
- * Copy non cmpr data
+ * Copy non cmpr data.
* 0x3FFF == ((LZNT_CHUNK_SIZE + 2 - 3) | 0x3000)
*/
cmpr[0] = 0xff;
@@ -233,38 +234,38 @@ static inline ssize_t decompress_chunk(u8 *unc, u8 *unc_end, const u8 *cmpr,
u16 pair;
size_t offset, length;
- /* Do decompression until pointers are inside range */
+ /* Do decompression until pointers are inside range. */
while (up < unc_end && cmpr < cmpr_end) {
/* Correct index */
while (unc + s_max_off[index] < up)
index += 1;
- /* Check the current flag for zero */
+ /* Check the current flag for zero. */
if (!(ch & (1 << bit))) {
- /* Just copy byte */
+ /* Just copy byte. */
*up++ = *cmpr++;
goto next;
}
- /* Check for boundary */
+ /* Check for boundary. */
if (cmpr + 1 >= cmpr_end)
return -EINVAL;
- /* Read a short from little endian stream */
+ /* Read a short from little endian stream. */
pair = cmpr[1];
pair <<= 8;
pair |= cmpr[0];
cmpr += 2;
- /* Translate packed information into offset and length */
+ /* Translate packed information into offset and length. */
length = parse_pair(pair, &offset, index);
- /* Check offset for boundary */
+ /* Check offset for boundary. */
if (unc + offset > up)
return -EINVAL;
- /* Truncate the length if necessary */
+ /* Truncate the length if necessary. */
if (up + length >= unc_end)
length = unc_end - up;
@@ -273,7 +274,7 @@ static inline ssize_t decompress_chunk(u8 *unc, u8 *unc_end, const u8 *cmpr,
*up = *(up - offset);
next:
- /* Advance flag bit value */
+ /* Advance flag bit value. */
bit = (bit + 1) & 7;
if (!bit) {
@@ -284,13 +285,14 @@ next:
}
}
- /* return the size of uncompressed data */
+ /* Return the size of uncompressed data. */
return up - unc;
}
/*
- * 0 - standard compression
- * !0 - best compression, requires a lot of cpu
+ * get_lznt_ctx
+ * @level: 0 - Standard compression.
+ * !0 - Best compression, requires a lot of cpu.
*/
struct lznt *get_lznt_ctx(int level)
{
@@ -303,11 +305,11 @@ struct lznt *get_lznt_ctx(int level)
}
/*
- * compress_lznt
+ * compress_lznt - Compresses @unc into @cmpr
*
- * Compresses "unc" into "cmpr"
- * +x - ok, 'cmpr' contains 'final_compressed_size' bytes of compressed data
- * 0 - input buffer is full zero
+ * Return:
+ * * +x - Ok, @cmpr contains 'final_compressed_size' bytes of compressed data.
+ * * 0 - Input buffer is full zero.
*/
size_t compress_lznt(const void *unc, size_t unc_size, void *cmpr,
size_t cmpr_size, struct lznt *ctx)
@@ -327,7 +329,7 @@ size_t compress_lznt(const void *unc, size_t unc_size, void *cmpr,
match = &longest_match_best;
}
- /* compression cycle */
+ /* Compression cycle. */
for (; unc_chunk < unc_end; unc_chunk += LZNT_CHUNK_SIZE) {
cmpr_size = 0;
err = compress_chunk(match, unc_chunk, unc_end, p, end,
@@ -348,9 +350,7 @@ size_t compress_lznt(const void *unc, size_t unc_size, void *cmpr,
}
/*
- * decompress_lznt
- *
- * decompresses "cmpr" into "unc"
+ * decompress_lznt - Decompress @cmpr into @unc.
*/
ssize_t decompress_lznt(const void *cmpr, size_t cmpr_size, void *unc,
size_t unc_size)
@@ -364,24 +364,24 @@ ssize_t decompress_lznt(const void *cmpr, size_t cmpr_size, void *unc,
if (cmpr_size < sizeof(short))
return -EINVAL;
- /* read chunk header */
+ /* Read chunk header. */
chunk_hdr = cmpr_chunk[1];
chunk_hdr <<= 8;
chunk_hdr |= cmpr_chunk[0];
- /* loop through decompressing chunks */
+ /* Loop through decompressing chunks. */
for (;;) {
size_t chunk_size_saved;
size_t unc_use;
size_t cmpr_use = 3 + (chunk_hdr & (LZNT_CHUNK_SIZE - 1));
- /* Check that the chunk actually fits the supplied buffer */
+ /* Check that the chunk actually fits the supplied buffer. */
if (cmpr_chunk + cmpr_use > cmpr_end)
return -EINVAL;
- /* First make sure the chunk contains compressed data */
+ /* First make sure the chunk contains compressed data. */
if (chunk_hdr & 0x8000) {
- /* Decompress a chunk and return if we get an error */
+ /* Decompress a chunk and return if we get an error. */
ssize_t err =
decompress_chunk(unc_chunk, unc_end,
cmpr_chunk + sizeof(chunk_hdr),
@@ -390,7 +390,7 @@ ssize_t decompress_lznt(const void *cmpr, size_t cmpr_size, void *unc,
return err;
unc_use = err;
} else {
- /* This chunk does not contain compressed data */
+ /* This chunk does not contain compressed data. */
unc_use = unc_chunk + LZNT_CHUNK_SIZE > unc_end
? unc_end - unc_chunk
: LZNT_CHUNK_SIZE;
@@ -404,21 +404,21 @@ ssize_t decompress_lznt(const void *cmpr, size_t cmpr_size, void *unc,
unc_use);
}
- /* Advance pointers */
+ /* Advance pointers. */
cmpr_chunk += cmpr_use;
unc_chunk += unc_use;
- /* Check for the end of unc buffer */
+ /* Check for the end of unc buffer. */
if (unc_chunk >= unc_end)
break;
- /* Proceed the next chunk */
+ /* Proceed the next chunk. */
if (cmpr_chunk > cmpr_end - 2)
break;
chunk_size_saved = LZNT_CHUNK_SIZE;
- /* read chunk header */
+ /* Read chunk header. */
chunk_hdr = cmpr_chunk[1];
chunk_hdr <<= 8;
chunk_hdr |= cmpr_chunk[0];
@@ -426,12 +426,12 @@ ssize_t decompress_lznt(const void *cmpr, size_t cmpr_size, void *unc,
if (!chunk_hdr)
break;
- /* Check the size of unc buffer */
+ /* Check the size of unc buffer. */
if (unc_use < chunk_size_saved) {
size_t t1 = chunk_size_saved - unc_use;
u8 *t2 = unc_chunk + t1;
- /* 'Zero' memory */
+ /* 'Zero' memory. */
if (t2 >= unc_end)
break;
@@ -440,13 +440,13 @@ ssize_t decompress_lznt(const void *cmpr, size_t cmpr_size, void *unc,
}
}
- /* Check compression boundary */
+ /* Check compression boundary. */
if (cmpr_chunk > cmpr_end)
return -EINVAL;
/*
* The unc size is just a difference between current
- * pointer and original one
+ * pointer and original one.
*/
return PtrOffset(unc, unc_chunk);
}
generated by cgit (git 2.34.1) at 2024-06-30 18:26:09 +0000