Use right shift to avoid 64-bit divisions.
These divisions are needed to convert from file length (potentially
over 32-bit range) to block number, so result and remainder are
guaranteed to fit in 32-bit integers.
Signed-off-by: Mauro Condarelli <mc5...@mclink.it>
---
Changes in v2:
- replace division with right shift (Daniel Schwierzeck).
- remove vocore2-specific change (Daniel Schwierzeck).
- add warning to Kconfig about CONFIG_SYS_MALLOC_LEN (Tom Rini).
fs/squashfs/Kconfig | 2 ++
fs/squashfs/sqfs.c | 30 +++++++++++++++---------------
fs/squashfs/sqfs_inode.c | 6 +++---
3 files changed, 20 insertions(+), 18 deletions(-)
diff --git a/fs/squashfs/Kconfig b/fs/squashfs/Kconfig
index 54ab1618f1..7c3f83d007 100644
--- a/fs/squashfs/Kconfig
+++ b/fs/squashfs/Kconfig
@@ -9,3 +9,5 @@ config FS_SQUASHFS
filesystem use, for archival use (i.e. in cases where a .tar.gz file
may be used), and in constrained block device/memory systems (e.g.
embedded systems) where low overhead is needed.
+ WARNING: if compression is enabled SquashFS needs a large amount
+ of dynamic memory; make sure CONFIG_SYS_MALLOC_LEN >= 0x4000.
diff --git a/fs/squashfs/sqfs.c b/fs/squashfs/sqfs.c
index 15208b4dab..90e6848e6c 100644
--- a/fs/squashfs/sqfs.c
+++ b/fs/squashfs/sqfs.c
@@ -85,10 +85,10 @@ static int sqfs_calc_n_blks(__le64 start, __le64 end, u64
*offset)
u64 start_, table_size;
table_size = le64_to_cpu(end) - le64_to_cpu(start);
- start_ = le64_to_cpu(start) / ctxt.cur_dev->blksz;
- *offset = le64_to_cpu(start) - (start_ * ctxt.cur_dev->blksz);
+ start_ = le64_to_cpu(start) >> ctxt.cur_dev->log2blksz;
+ *offset = le64_to_cpu(start) - (start_ << ctxt.cur_dev->log2blksz);
- return DIV_ROUND_UP(table_size + *offset, ctxt.cur_dev->blksz);
+ return (table_size + *offset + ctxt.cur_dev->blksz - 1) >>
ctxt.cur_dev->log2blksz;
}
/*
@@ -109,8 +109,8 @@ static int sqfs_frag_lookup(u32 inode_fragment_index,
if (inode_fragment_index >= get_unaligned_le32(&sblk->fragments))
return -EINVAL;
- start = get_unaligned_le64(&sblk->fragment_table_start) /
- ctxt.cur_dev->blksz;
+ start = get_unaligned_le64(&sblk->fragment_table_start) >>
+ ctxt.cur_dev->log2blksz;
n_blks = sqfs_calc_n_blks(sblk->fragment_table_start,
sblk->export_table_start,
&table_offset);
@@ -135,7 +135,7 @@ static int sqfs_frag_lookup(u32 inode_fragment_index,
start_block = get_unaligned_le64(table + table_offset + block *
sizeof(u64));
- start = start_block / ctxt.cur_dev->blksz;
+ start = start_block >> ctxt.cur_dev->log2blksz;
n_blks = sqfs_calc_n_blks(cpu_to_le64(start_block),
sblk->fragment_table_start, &table_offset);
@@ -641,8 +641,8 @@ static int sqfs_read_inode_table(unsigned char
**inode_table)
table_size = get_unaligned_le64(&sblk->directory_table_start) -
get_unaligned_le64(&sblk->inode_table_start);
- start = get_unaligned_le64(&sblk->inode_table_start) /
- ctxt.cur_dev->blksz;
+ start = get_unaligned_le64(&sblk->inode_table_start) >>
+ ctxt.cur_dev->log2blksz;
n_blks = sqfs_calc_n_blks(sblk->inode_table_start,
sblk->directory_table_start, &table_offset);
@@ -725,8 +725,8 @@ static int sqfs_read_directory_table(unsigned char
**dir_table, u32 **pos_list)
/* DIRECTORY TABLE */
table_size = get_unaligned_le64(&sblk->fragment_table_start) -
get_unaligned_le64(&sblk->directory_table_start);
- start = get_unaligned_le64(&sblk->directory_table_start) /
- ctxt.cur_dev->blksz;
+ start = get_unaligned_le64(&sblk->directory_table_start) >>
+ ctxt.cur_dev->log2blksz;
n_blks = sqfs_calc_n_blks(sblk->directory_table_start,
sblk->fragment_table_start, &table_offset);
@@ -1334,11 +1334,11 @@ int sqfs_read(const char *filename, void *buf, loff_t
offset, loff_t len,
}
for (j = 0; j < datablk_count; j++) {
- start = data_offset / ctxt.cur_dev->blksz;
+ start = data_offset >> ctxt.cur_dev->log2blksz;
table_size = SQFS_BLOCK_SIZE(finfo.blk_sizes[j]);
table_offset = data_offset - (start * ctxt.cur_dev->blksz);
- n_blks = DIV_ROUND_UP(table_size + table_offset,
- ctxt.cur_dev->blksz);
+ n_blks = (table_size + table_offset + ctxt.cur_dev->blksz - 1)
>>
+ ctxt.cur_dev->log2blksz;
data_buffer = malloc_cache_aligned(n_blks *
ctxt.cur_dev->blksz);
@@ -1388,10 +1388,10 @@ int sqfs_read(const char *filename, void *buf, loff_t
offset, loff_t len,
goto free_buffer;
}
- start = frag_entry.start / ctxt.cur_dev->blksz;
+ start = frag_entry.start >> ctxt.cur_dev->log2blksz;
table_size = SQFS_BLOCK_SIZE(frag_entry.size);
table_offset = frag_entry.start - (start * ctxt.cur_dev->blksz);
- n_blks = DIV_ROUND_UP(table_size + table_offset, ctxt.cur_dev->blksz);
+ n_blks = (table_size + table_offset + ctxt.cur_dev->blksz - 1) >>
ctxt.cur_dev->log2blksz;
fragment = malloc_cache_aligned(n_blks * ctxt.cur_dev->blksz);
diff --git a/fs/squashfs/sqfs_inode.c b/fs/squashfs/sqfs_inode.c
index 1368f3063c..5dbf945c80 100644
--- a/fs/squashfs/sqfs_inode.c
+++ b/fs/squashfs/sqfs_inode.c
@@ -10,7 +10,7 @@
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
-#include <string.h>
+#include <part.h>
#include "sqfs_decompressor.h"
#include "sqfs_filesystem.h"
@@ -68,9 +68,9 @@ int sqfs_inode_size(struct squashfs_base_inode *inode, u32
blk_size)
unsigned int blk_list_size;
if (fragment == 0xFFFFFFFF)
- blk_list_size = DIV_ROUND_UP(file_size, blk_size);
+ blk_list_size = (file_size + blk_size - 1) >>
LOG2(blk_size);
else
- blk_list_size = file_size / blk_size;
+ blk_list_size = file_size > LOG2(blk_size);
return sizeof(*lreg) + blk_list_size * sizeof(u32);
}
--
2.25.1
