This patch introduces setup_dtb_prop(), which is used for dtb
operations. The code is extracted from zImage_arm_load, and this patch
makes memory grown computation more accurate.
Signed-off-by: Wang Nan <wangnan0 at huawei.com>
Cc: Simon Horman <horms at verge.net.au>
Cc: Dave Young <dyoung at redhat.com>
Cc: Geng Hui <hui.geng at huawei.com>
---
kexec/arch/arm/kexec-zImage-arm.c | 96 ++++++++++++++++++++++++++++-----------
1 file changed, 70 insertions(+), 26 deletions(-)
diff --git a/kexec/arch/arm/kexec-zImage-arm.c b/kexec/arch/arm/kexec-zImage-arm.c
index 8a35018..977254e 100644
--- a/kexec/arch/arm/kexec-zImage-arm.c
+++ b/kexec/arch/arm/kexec-zImage-arm.c
@@ -216,6 +216,68 @@ int atag_arm_load(struct kexec_info *info, unsigned long base,
return 0;
}
+static int setup_dtb_prop(char **bufp, off_t *sizep, const char *node_name,
+ const char *prop_name, const void *val, int len)
+{
+ char *dtb_buf;
+ int off;
+
+ if ((bufp == NULL) || (sizep == NULL) || (*bufp == NULL))
+ die("Internal error\n");
+
+ dtb_buf = *bufp;
+
+ /*
+ * Potential memory usage grown:
+ *
+ * 1. if fdt_add_subnode is called:
+ * sizeof(struct fdt_node_header) + FDT_TAGALIGN(nodename+1) + FDT_TAGSIZE
+ * // see fdt_add_subnode_namelen()
+ *
+ * 2. in fdt_setprop, if _fdt_add_property is called:
+ * a) strlen(prop_name) + 1 // see _fdt_find_add_string()
+ * b) sizeof(struct fdt_property) + FDT_TAGALIGN(len)
+ * // see _fdt_add_property()
+ *
+ * FDT_TAGALIGN is (FDT_ALIGN((x), FDT_TAGSIZE)), which is same
+ * to _ALIGN(x, FDT_TAGSIZE).
+ */
+
+ *sizep = fdt_totalsize(*bufp) +
+ /* fdt_add_subnode -> fdt_add_subnode_namelen */
+ sizeof(struct fdt_node_header) +
+ _ALIGN(strlen(node_name) + 1, FDT_TAGSIZE) +
+ FDT_TAGSIZE +
+ /* fdt_setprop -> _fdt_add_property -> _fdt_find_add_string */
+ strlen(prop_name) + 1 +
+ /* fdt_setprop -> _fdt_add_property */
+ sizeof(struct fdt_property) + _ALIGN(len, FDT_TAGSIZE);
+
+ dtb_buf = xrealloc(dtb_buf, *sizep);
+ if (dtb_buf == NULL)
+ die("xrealloc failed\n");
+ *bufp = dtb_buf;
+
+ fdt_set_totalsize(dtb_buf, *sizep);
+
+ /* check if the subnode already exists */
+ off = fdt_path_offset(dtb_buf, node_name);
+
+ if (off == -FDT_ERR_NOTFOUND)
+ off = fdt_add_subnode(dtb_buf, off, node_name);
+ if (off < 0) {
+ fprintf(stderr, "FDT: Error adding %s node.\n", node_name);
+ return -1;
+ }
+ if (fdt_setprop(dtb_buf, off, prop_name,
+ val, len) != 0) {
+ fprintf(stderr, "FDT: Error setting %s/%s property.\n",
+ node_name, prop_name);
+ return -1;
+ }
+ return 0;
+}
+
int zImage_arm_load(int argc, char **argv, const char *buf, off_t len,
struct kexec_info *info)
{
@@ -375,32 +437,14 @@ int zImage_arm_load(int argc, char **argv, const char *buf, off_t len,
}
if (command_line) {
- const char *node_name = "/chosen";
- const char *prop_name = "bootargs";
- int off;
-
- dtb_length = fdt_totalsize(dtb_buf) + 1024 +
- strlen(command_line);
- dtb_buf = xrealloc(dtb_buf, dtb_length);
- fdt_set_totalsize(dtb_buf, dtb_length);
-
- /* check if a /choosen subnode already exists */
- off = fdt_path_offset(dtb_buf, node_name);
-
- if (off == -FDT_ERR_NOTFOUND)
- off = fdt_add_subnode(dtb_buf, off, node_name);
-
- if (off < 0) {
- fprintf(stderr, "FDT: Error adding %s node.\n", node_name);
- return -1;
- }
-
- if (fdt_setprop(dtb_buf, off, prop_name,
- command_line, strlen(command_line) + 1) != 0) {
- fprintf(stderr, "FDT: Error setting %s/%s property.\n",
- node_name, prop_name);
- return -1;
- }
+ /*
+ * Error should have been reported so
+ * directly return -1
+ */
+ if (setup_dtb_prop(&dtb_buf, &dtb_length, "/chosen",
+ "bootargs", command_line,
+ strlen(command_line) + 1))
+ return -1;
}
} else {
/*
--
1.8.3.4
