ext4: Allow reading files with non-zero offset, clamp read len

Support was already implemented, but not hooked up. This fixes several
fails in the test cases.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>

diff --git a/common/spl/spl_ext.c b/common/spl/spl_ext.c
index b93e1eacd3033bc10f3c528791a43153b1151e79..1b8e15e37d6af1e0b06767a9780cf602c02a4ca9 100644 (file)
--- a/common/spl/spl_ext.c
+++ b/common/spl/spl_ext.c
@@ -42,7 +42,7 @@ int spl_load_image_ext(struct spl_image_info *spl_image,
                puts("spl: ext4fs_open failed\n");
                goto end;
        }
-       err = ext4fs_read((char *)header, sizeof(struct image_header), &actlen);
+       err = ext4fs_read((char *)header, 0, sizeof(struct image_header), &actlen);
        if (err < 0) {
                puts("spl: ext4fs_read failed\n");
                goto end;
@@ -54,7 +54,7 @@ int spl_load_image_ext(struct spl_image_info *spl_image,
                goto end;
        }
 
-       err = ext4fs_read((char *)spl_image->load_addr, filelen, &actlen);
+       err = ext4fs_read((char *)spl_image->load_addr, 0, filelen, &actlen);
 
 end:
 #ifdef CONFIG_SPL_LIBCOMMON_SUPPORT
@@ -97,7 +97,7 @@ int spl_load_image_ext_os(struct spl_image_info *spl_image,
                        puts("spl: ext4fs_open failed\n");
                        goto defaults;
                }
-               err = ext4fs_read((void *)CONFIG_SYS_SPL_ARGS_ADDR, filelen, &actlen);
+               err = ext4fs_read((void *)CONFIG_SYS_SPL_ARGS_ADDR, 0, filelen, &actlen);
                if (err < 0) {
                        printf("spl: error reading image %s, err - %d, falling back to default\n",
                               file, err);
@@ -127,7 +127,7 @@ defaults:
        if (err < 0)
                puts("spl: ext4fs_open failed\n");
 
-       err = ext4fs_read((void *)CONFIG_SYS_SPL_ARGS_ADDR, filelen, &actlen);
+       err = ext4fs_read((void *)CONFIG_SYS_SPL_ARGS_ADDR, 0, filelen, &actlen);
        if (err < 0) {
 #ifdef CONFIG_SPL_LIBCOMMON_SUPPORT
                printf("%s: error reading image %s, err - %d\n",

diff --git a/fs/ext4/ext4fs.c b/fs/ext4/ext4fs.c
index 30787377708cb11db671a1342440faab16dcc662..7187dcfb0565566f0f778bd2191df7093a19a2e1 100644 (file)
--- a/fs/ext4/ext4fs.c
+++ b/fs/ext4/ext4fs.c
@@ -65,8 +65,8 @@ int ext4fs_read_file(struct ext2fs_node *node, loff_t pos,
        short status;
 
        /* Adjust len so it we can't read past the end of the file. */
-       if (len > filesize)
-               len = filesize;
+       if (len + pos > filesize)
+               len = (filesize - pos);
 
        blockcnt = lldiv(((len + pos) + blocksize - 1), blocksize);
 
@@ -190,12 +190,12 @@ int ext4fs_size(const char *filename, loff_t *size)
        return ext4fs_open(filename, size);
 }
 
-int ext4fs_read(char *buf, loff_t len, loff_t *actread)
+int ext4fs_read(char *buf, loff_t offset, loff_t len, loff_t *actread)
 {
        if (ext4fs_root == NULL || ext4fs_file == NULL)
-               return 0;
+               return -1;
 
-       return ext4fs_read_file(ext4fs_file, 0, len, buf, actread);
+       return ext4fs_read_file(ext4fs_file, offset, len, buf, actread);
 }
 
 int ext4fs_probe(struct blk_desc *fs_dev_desc,
@@ -217,11 +217,6 @@ int ext4_read_file(const char *filename, void *buf, loff_t offset, loff_t len,
        loff_t file_len;
        int ret;
 
-       if (offset != 0) {
-               printf("** Cannot support non-zero offset **\n");
-               return -1;
-       }
-
        ret = ext4fs_open(filename, &file_len);
        if (ret < 0) {
                printf("** File not found %s **\n", filename);
@@ -231,7 +226,7 @@ int ext4_read_file(const char *filename, void *buf, loff_t offset, loff_t len,
        if (len == 0)
                len = file_len;
 
-       return ext4fs_read(buf, len, len_read);
+       return ext4fs_read(buf, offset, len, len_read);
 }
 
 int ext4fs_uuid(char *uuid_str)

diff --git a/include/ext4fs.h b/include/ext4fs.h
index 965cd9e9c507affcd5316ca161499493aab386a5..bb556391072516a6fee6ffb662ab552e96ad7c9e 100644 (file)
--- a/include/ext4fs.h
+++ b/include/ext4fs.h
@@ -135,7 +135,7 @@ int ext4_write_file(const char *filename, void *buf, loff_t offset, loff_t len,
 
 struct ext_filesystem *get_fs(void);
 int ext4fs_open(const char *filename, loff_t *len);
-int ext4fs_read(char *buf, loff_t len, loff_t *actread);
+int ext4fs_read(char *buf, loff_t offset, loff_t len, loff_t *actread);
 int ext4fs_mount(unsigned part_length);
 void ext4fs_close(void);
 void ext4fs_reinit_global(void);