近想起來還有一塊mini2440的開發板很久沒有使用了，所以想移植一個基於linux3.10的linux系統，但是在移植yaffs2文件系統的時候出現了一些問題，我將其記錄下來給其他同學解決同樣的問題提供幫助。
1. 首先通過git下載yaffs2代碼。然後進入yaffs2文件夾中執行patch-ker.sh，給linux源代碼打上patch。
$ git clone git://www.aleph1.co.uk/yaffs2 $ cd yaffs2/ $ ./patch-ker.sh c m /work/src/linux3.10.17/
2. 然後在linux的源代碼fs中多了一個yaffs2的文件夾，到此yaffs2文件系統就已經添加到linux3.10中了。在Linux內核源代碼根目錄運行：make menuconfig，移動上下按鍵進行配置：
File Systems ---> Miscellaneous filesystems ---> [*]YAFFS2 file system support並按空格選中它，這樣我們就在內核中添加了yaffs2文件系統的支持，按“Exit”退出內核配置。
3. 編譯linux源代碼。
$ make scripts/kconfig/conf --silentoldconfig Kconfig CHK include/generated/uapi/linux/version.h CHK include/generated/utsrelease.h make[1]: `include/generated/mach-types.h' is up to date. CALL scripts/checksyscalls.sh CC scripts/mod/devicetable-offsets.s GEN scripts/mod/devicetable-offsets.h HOSTCC scripts/mod/file2alias.o HOSTLD scripts/mod/modpost CHK include/generated/compile.h CC fs/yaffs2/yaffs_ecc.o CC fs/yaffs2/yaffs_vfs.o fs/yaffs2/yaffs_vfs.c: In function 'yaffs_proc_debug_write': fs/yaffs2/yaffs_vfs.c:3304: warning: comparison of distinct pointer types lacks a cast fs/yaffs2/yaffs_vfs.c: In function 'init_yaffs_fs': fs/yaffs2/yaffs_vfs.c:3398: error: implicit declaration of function 'create_proc_entry' fs/yaffs2/yaffs_vfs.c:3399: warning: assignment makes pointer from integer without a cast fs/yaffs2/yaffs_vfs.c:3402: error: dereferencing pointer to incomplete type fs/yaffs2/yaffs_vfs.c:3403: error: dereferencing pointer to incomplete type fs/yaffs2/yaffs_vfs.c:3404: error: dereferencing pointer to incomplete type make[2]: *** [fs/yaffs2/yaffs_vfs.o] Error 1 make[1]: *** [fs/yaffs2] Error 2 make: *** [fs] Error 2
編譯fs/yaffs2/yaffs_vfs.c時出現錯誤，function 'create_proc_entry'沒有申明。Google之後才知道原來這個接口在linux-3.10被刪除了，應該使用proc_create代替。
4. 修改fs/yaffs2/yaffs_vfs.c
@@ -3384,12 +3384,6 @@ static struct file_system_to_install fs_to_install[] = {
{NULL, 0}
};
+static const struct file_operations yaffs_fops = {
+ .owner = THIS_MODULE,
+ .read = yaffs_proc_read,
+ .write = yaffs_proc_write,
+};
+
static int __init init_yaffs_fs(void)
{
int error = 0;
@@ -3401,9 +3395,9 @@ static int __init init_yaffs_fs(void)
mutex_init(&yaffs_context_lock);
/* Install the proc_fs entries */
+ my_proc_entry = proc_create("yaffs",
+ S_IRUGO | S_IFREG, YPROC_ROOT, &yaffs_fops);
+#if 0
- my_proc_entry = create_proc_entry("yaffs",
- S_IRUGO | S_IFREG, YPROC_ROOT);
-
if (my_proc_entry) {
my_proc_entry->write_proc = yaffs_proc_write;
my_proc_entry->read_proc = yaffs_proc_read;
@@ -3411,7 +3405,7 @@ static int __init init_yaffs_fs(void)
} else {
return -ENOMEM;
}
+#endif
-
/* Now add the file system entries */
fsinst = fs_to_install;
我粘貼一下我修改後的代碼：
//add by jxm.begin
static const struct file_operations yaffs_fops = {
.owner = THIS_MODULE,
.read = yaffs_proc_read,
.write = yaffs_proc_write,
};
//add by jxm.end
static int __init init_yaffs_fs(void)
{
int error = 0;
struct file_system_to_install *fsinst;
yaffs_trace(YAFFS_TRACE_ALWAYS,
"yaffs built " __DATE__ " " __TIME__ " Installing.");
mutex_init(&yaffs_context_lock);
//add by jxm
my_proc_entry = proc_create("yaffs",S_IRUGO | S_IFREG, YPROC_ROOT, &yaffs_fops);
/* Install the proc_fs entries */
//add by jxm begin
#if 0（使用這個來註釋）
my_proc_entry = create_proc_entry("yaffs",
S_IRUGO | S_IFREG, YPROC_ROOT);
if (my_proc_entry) {
my_proc_entry->write_proc = yaffs_proc_write;
my_proc_entry->read_proc = yaffs_proc_read;
my_proc_entry->data = NULL;
} else {
return -ENOMEM;
}
#endif
//add by jxm.end
/* Now add the file system entries */
fsinst = fs_to_install;
while (fsinst->fst && !error) {
error = register_filesystem(fsinst->fst);
if (!error)
fsinst->installed = 1;
fsinst++;
}
/* Any errors? uninstall */
if (error) {
fsinst = fs_to_install;
while (fsinst->fst) {
if (fsinst->installed) {
unregister_filesystem(fsinst->fst);
fsinst->installed = 0;
}
fsinst++;
}
}
return error;
}
5. 修改之後保存，然後再編譯就可以成功了。
$ make zImage CHK include/generated/uapi/linux/version.h CHK include/generated/utsrelease.h make[1]: `include/generated/mach-types.h' is up to date. CALL scripts/checksyscalls.sh CC scripts/mod/devicetable-offsets.s GEN scripts/mod/devicetable-offsets.h HOSTCC scripts/mod/file2alias.o HOSTLD scripts/mod/modpost CHK include/generated/compile.h CC fs/yaffs2/yaffs_vfs.o fs/yaffs2/yaffs_vfs.c: In function 'yaffs_proc_debug_write': fs/yaffs2/yaffs_vfs.c:3304: warning: comparison of distinct pointer types lacks a cast fs/yaffs2/yaffs_vfs.c: At top level: fs/yaffs2/yaffs_vfs.c:3389: warning: initialization from incompatible pointer type fs/yaffs2/yaffs_vfs.c:3390: warning: initialization from incompatible pointer type CC fs/yaffs2/yaffs_guts.o CC fs/yaffs2/yaffs_checkptrw.o CC fs/yaffs2/yaffs_packedtags1.o CC fs/yaffs2/yaffs_packedtags2.o CC fs/yaffs2/yaffs_nand.o CC fs/yaffs2/yaffs_tagscompat.o CC fs/yaffs2/yaffs_tagsmarshall.o CC fs/yaffs2/yaffs_mtdif.o CC fs/yaffs2/yaffs_nameval.o CC fs/yaffs2/yaffs_attribs.o CC fs/yaffs2/yaffs_allocator.o CC fs/yaffs2/yaffs_yaffs1.o CC fs/yaffs2/yaffs_yaffs2.o CC fs/yaffs2/yaffs_bitmap.o CC fs/yaffs2/yaffs_summary.o CC fs/yaffs2/yaffs_verify.o LD fs/yaffs2/yaffs.o LD fs/yaffs2/built-in.o LD fs/built-in.o LINK vmlinux LD vmlinux.o MODPOST vmlinux.o GEN .version CHK include/generated/compile.h UPD include/generated/compile.h CC init/version.o LD init/built-in.o KSYM .tmp_kallsyms1.o KSYM .tmp_kallsyms2.o LD vmlinux SORTEX vmlinux SYSMAP System.map OBJCOPY arch/arm/boot/Image Kernel: arch/arm/boot/Image is ready GZIP arch/arm/boot/compressed/piggy.gzip AS arch/arm/boot/compressed/piggy.gzip.o LD arch/arm/boot/compressed/vmlinux OBJCOPY arch/arm/boot/zImage Kernel: arch/arm/boot/zImage is ready