fs/ext4/ext4fs.c, fs/fs.c fs/fat/fat_write.c: Adjust 64bit math methods

The changes to introduce loff_t into filesize means that we need to do 64bit math on 32bit platforms. Make sure we use the right wrappers for these operations.

Cc Daniel Schwierzeck <[email protected]>

Cc Suriyan Ramasami <[email protected]>

Cc Simon Glass <[email protected]>

Signed-off-by Tom Rini <[email protected]>

---
 fs/ext4/ext4fs.c   |   11 ++++++-----
 fs/fat/fat_write.c |   10 ++++++----
 fs/fs.c            |    6 ++++--
 3 files changed, 16 insertions(+), 11 deletions(-)

fs/ext4/ext4fs.c +4 -3

index 943b5bc..258b9379 100644
@@ -25,6 +25,7 @@
 #include <ext_common.h>
 #include <ext4fs.h>
 #include "ext4_common.h"
+#include <div64.h>
 
 int ext4fs_symlinknest;
 struct ext_filesystem ext_fs;

@@ -67,11 +68,11 @@ int ext4fs_read_file(struct ext2fs_node *node, loff_t pos,
        if (len > filesize)
                len = filesize;
 
-       blockcnt = ((len + pos) + blocksize - 1) / blocksize;
+       blockcnt = lldiv(((len + pos) + blocksize - 1), blocksize);
 
-       for (i = pos / blocksize; i < blockcnt; i++) {
+       for (i = lldiv(pos, blocksize); i < blockcnt; i++) {
                lbaint_t blknr;
-               int blockoff = pos % blocksize;
+               int blockoff = pos - (blocksize * i);
                int blockend = blocksize;
                int skipfirst = 0;
                blknr = read_allocated_block(&(node->inode), i);

fs/ext4/ext4fs.c +1 -1

                        /* The last portion is exactly blocksize. */
                        if (!blockend)

@@ -90,7 +91,7 @@ int ext4fs_read_file(struct ext2fs_node *node, loff_t pos,
                }
 
                /* First block. */
-               if (i == pos / blocksize) {
+               if (i == lldiv(pos, blocksize)) {
                        skipfirst = blockoff;
                        blockend -= skipfirst;
                }

fs/fat/fat_write.c +6 -4

index 88dd495..473723b 100644
@@ -13,6 +13,8 @@
 #include <asm/byteorder.h>
 #include <part.h>
 #include <linux/ctype.h>
+#include <div64.h>
+#include <linux/math64.h>
 #include "fat.c"
 
 static void uppercase(char *str, int len)

@@ -770,7 +772,7 @@ static void fill_dentry(fsdata *mydata, dir_entry *dentptr,
  */
 static int check_overflow(fsdata *mydata, __u32 clustnum, loff_t size)
 {
-       __u32 startsect, sect_num;
+       __u32 startsect, sect_num, offset;
 
        if (clustnum > 0) {
                startsect = mydata->data_begin +

@@ -779,13 +781,13 @@ static int check_overflow(fsdata *mydata, __u32 clustnum, loff_t size)
                startsect = mydata->rootdir_sect;
        }
 
-       sect_num = size / mydata->sect_size;
-       if (size % mydata->sect_size)
+       sect_num = div_u64_rem(size, mydata->sect_size, &offset);
+
+       if (offset != 0)
                sect_num++;
 
        if (startsect + sect_num > cur_part_info.start + total_sector)
                return -1;
-
        return 0;
 }
 

fs/fs.c +2 -0

index 3da7860..52078139 100644
@@ -23,6 +23,8 @@
 #include <fs.h>
 #include <sandboxfs.h>
 #include <asm/io.h>
+#include <div64.h>
+#include <linux/math64.h>
 
 DECLARE_GLOBAL_DATA_PTR;
 

fs/fs.c +0 -1

                puts(")");
        }
        puts("\n");
--

1.7.9.5

Hi Tom,

Quoted 8 lines · Tom Rini

The changes to introduce loff_t into filesize means that we need to do 64bit math on 32bit platforms. Make sure we use the right wrappers for these operations.

Cc Daniel Schwierzeck <[email protected]>

Cc Suriyan Ramasami <[email protected]>

Cc Simon Glass <[email protected]>

Signed-off-by Tom Rini <[email protected]>

This fixes things for me, thanks! But please see below.

Quoted 35 lines

---
 fs/ext4/ext4fs.c   |   11 ++++++-----
 fs/fat/fat_write.c |   10 ++++++----
 fs/fs.c            |    6 ++++--
 3 files changed, 16 insertions(+), 11 deletions(-)

fs/ext4/ext4fs.c +4 -3

index 943b5bc..258b9379 100644
@@ -25,6 +25,7 @@
 #include <ext_common.h>
 #include <ext4fs.h>
 #include "ext4_common.h"
+#include <div64.h>
 
 int ext4fs_symlinknest;
 struct ext_filesystem ext_fs;

@@ -67,11 +68,11 @@ int ext4fs_read_file(struct ext2fs_node *node, loff_t pos,
        if (len > filesize)
                len = filesize;
 
-       blockcnt = ((len + pos) + blocksize - 1) / blocksize;
+       blockcnt = lldiv(((len + pos) + blocksize - 1), blocksize);
 
-       for (i = pos / blocksize; i < blockcnt; i++) {
+       for (i = lldiv(pos, blocksize); i < blockcnt; i++) {
                lbaint_t blknr;
-               int blockoff = pos % blocksize;
+               int blockoff = pos - (blocksize * i);
                int blockend = blocksize;
                int skipfirst = 0;
                blknr = read_allocated_block(&(node->inode), i);

@@ -82,7 +83,7 @@ int ext4fs_read_file(struct ext2fs_node *node, loff_t pos,
 

fs/ext4/ext4fs.c int ext4fs_read_file(struct ext2fs_node *node, loff_t pos, · line 86

Quoted 4 lines

fs/ext4/ext4fs.c +1 -1

                /* Last block.  */
                if (i == blockcnt - 1) {
-                       blockend = (len + pos) % blocksize;
+                       blockend = (len + pos) - (blocksize * i);

Actually do you think it would be clearer to use div_u64_rem() here?

Quoted 66 lines

fs/ext4/ext4fs.c +1 -1

                        /* The last portion is exactly blocksize. */
                        if (!blockend)

@@ -90,7 +91,7 @@ int ext4fs_read_file(struct ext2fs_node *node, loff_t pos,
                }
 
                /* First block. */
-               if (i == pos / blocksize) {
+               if (i == lldiv(pos, blocksize)) {
                        skipfirst = blockoff;
                        blockend -= skipfirst;
                }

fs/fat/fat_write.c +6 -4

index 88dd495..473723b 100644
@@ -13,6 +13,8 @@
 #include <asm/byteorder.h>
 #include <part.h>
 #include <linux/ctype.h>
+#include <div64.h>
+#include <linux/math64.h>
 #include "fat.c"
 
 static void uppercase(char *str, int len)

@@ -770,7 +772,7 @@ static void fill_dentry(fsdata *mydata, dir_entry *dentptr,
  */
 static int check_overflow(fsdata *mydata, __u32 clustnum, loff_t size)
 {
-       __u32 startsect, sect_num;
+       __u32 startsect, sect_num, offset;
 
        if (clustnum > 0) {
                startsect = mydata->data_begin +

@@ -779,13 +781,13 @@ static int check_overflow(fsdata *mydata, __u32 clustnum, loff_t size)
                startsect = mydata->rootdir_sect;
        }
 
-       sect_num = size / mydata->sect_size;
-       if (size % mydata->sect_size)
+       sect_num = div_u64_rem(size, mydata->sect_size, &offset);
+
+       if (offset != 0)
                sect_num++;
 
        if (startsect + sect_num > cur_part_info.start + total_sector)
                return -1;
-
        return 0;
 }
 

fs/fs.c +2 -0

index 3da7860..52078139 100644
@@ -23,6 +23,8 @@
 #include <fs.h>
 #include <sandboxfs.h>
 #include <asm/io.h>
+#include <div64.h>
+#include <linux/math64.h>
 
 DECLARE_GLOBAL_DATA_PTR;
 

fs/fs.c int do_load(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[], · line 404

Quoted 5 lines

fs/fs.c +1 -1

@@ -399,7 +401,7 @@ int do_load(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[],
        printf("%llu bytes read in %lu ms", len_read, time);
        if (time > 0) {
                puts(" (");
-               print_size(len_read / time * 1000, "/s");
+               print_size(div_u64(len_read, time * 1000), "/s");

The old code multiplies by 1000 but the new code divides. I think it should be:

               print_size(div_u64(len_read, time) * 1000, "/s");

fs/fs.c int do_save(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[], · line 474

Quoted 9 lines

fs/fs.c +1 -1

                puts(")");
        }
        puts("\n");

@@ -469,7 +471,7 @@ int do_save(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[],
        printf("%llu bytes written in %lu ms", len, time);
        if (time > 0) {
                puts(" (");
-               print_size(len / time * 1000, "/s");
+               print_size(div_u64(len, time * 1000), "/s");

and here.