Remove duplicate code where possible by using reusable functions.
Signed-off-by: Srikar Dronamraju <sri...@linux.vnet.ibm.com>
---
kernel/utrace-gdb.c | 272 +++++++++++++++++++++++----------------------------
1 files changed, 123 insertions(+), 149 deletions(-)
diff --git a/kernel/utrace-gdb.c b/kernel/utrace-gdb.c
index f44b3c0..97811c2 100644
--- a/kernel/utrace-gdb.c
+++ b/kernel/utrace-gdb.c
@@ -793,6 +793,84 @@ static int gdb_remote_register_info(struct gdb_connection
*p,
return -ENOENT;
}
+static inline int fetch_remote_register_info(struct gdb_connection *p,
+ struct task_struct *task,
+ int index,
+ unsigned *pos,
+ unsigned *count,
+ unsigned *bytes)
+{
+ int rsn;
+
+ rsn = gdb_remote_register_info(p, task, index, pos, count, bytes);
+ pr_debug("gdb register %u => rsn %d p%u c%u b%u\n", index, rsn,
+ *pos, *count, *bytes);
+ if (rsn > 0) {
+ /*
+ * If we want to extract register data, make sure we're
+ * fetching at least that much.
+ */
+ BUG_ON(*count > 0 && *count < *bytes);
+ /* Assert reg_contents size is right. */
+ BUG_ON(MAX_REG_WIDTH < *bytes || MAX_REG_WIDTH < *count);
+ }
+ return rsn;
+}
+
+static inline int get_set_regset_view(struct task_struct *task,
+ unsigned pos, unsigned count,
+ unsigned char *reg_contents,
+ int rsn, bool set)
+{
+ int rc;
+ const struct user_regset_view *rsv;
+ const struct user_regset *rs;
+
+ if (!count) {
+ if (!set)
+ memset(reg_contents, 0, MAX_REG_WIDTH);
+ return 0;
+ }
+
+ /* real register */
+ if (set)
+ BUG_ON(count > MAX_REG_WIDTH);
+
+ rsv = task_user_regset_view(task);
+ BUG_ON(rsn >= rsv->n);
+ rs = &rsv->regsets[rsn];
+
+ /* Extract the register values into reg_contents[]. */
+ if (set)
+ rc = (rs->set)(task, rs, pos, count, reg_contents, NULL);
+ else
+ rc = (rs->get)(task, rs, pos, count, reg_contents, NULL);
+
+ return rc;
+}
+
+static inline void prepare_regset_set(struct gdb_connection *p,
+ unsigned char *reg_contents,
+ size_t *start, unsigned bytes)
+{
+ int j;
+
+ /*
+ * 0-fill the register copy.
+ * XXX initialize it from rs->get() instead?
+ */
+ memset(reg_contents, 0, MAX_REG_WIDTH);
+
+ /*
+ * Hex-unconvert all the bytes.
+ * XXX: endianness adjust for count != bytes
+ */
+ for (j = 0; j < bytes; j++)
+ reg_contents[j] = byteme(p->input_buf[*start + 2 * j],
+ p->input_buf[*start + 2 * j + 1]);
+ *start += 2 * bytes;
+}
+
/*
* Process an entire, checksum-confirmed $command# at the front of
* p->input_buf[]. The input and output mutexes are being held.
@@ -880,50 +958,23 @@ static void handle_gdb_command_packet(struct
gdb_connection *p,
unsigned rs_count;
unsigned rs_pos;
unsigned bytes;
- const struct user_regset_view *rsv;
- const struct user_regset *rs;
+ int rsn;
unsigned char reg_contents[MAX_REG_WIDTH];
- int rsn = gdb_remote_register_info(p, task, i,
- &rs_pos, &rs_count,
- &bytes);
-
+ rsn = fetch_remote_register_info(p, task, i,
+ &rs_pos, &rs_count, &bytes);
if (rsn < 0)
break;
- /*
- * If we want to extract register data, make sure
- * we're fetching at least that much.
- */
- BUG_ON(rs_count > 0 && rs_count < bytes);
- /* Assert reg_contents size is right. */
- BUG_ON(sizeof(reg_contents) < bytes ||
- sizeof(reg_contents) < rs_count);
-
- if (rs_count) { /* real register */
- rsv = task_user_regset_view(task);
- BUG_ON(rsn >= rsv->n);
- rs = &rsv->regsets[rsn];
-
- /*
- * Extract the register values into
- * reg_contents[].
- */
- rc = (rs->get)(task, rs, rs_pos, rs_count,
- reg_contents, NULL);
- if (rc)
- break;
-
- } else { /* dummy value */
- memset(reg_contents, 0, sizeof(reg_contents));
- }
+ rc = get_set_regset_view(task, rs_pos, rs_count,
+ reg_contents, rsn, false);
+ if (rc)
+ break;
/*
* Hex-dump it.
* XXX: endianness adjust for count != bytes
*/
- /* pr_debug ("gdb register %d => rsn %d p%u c%u b%u (",
- i, rsn, rs_pos, rs_count, bytes); */
for (j = 0; j < bytes; j++) {
/* pr_debug("%02x", reg_contents[j]); */
push_output_hex(p, reg_contents[j]);
@@ -937,66 +988,27 @@ static void handle_gdb_command_packet(struct
gdb_connection *p,
i = 0;
op_start = 2; /* use as input pointer, past $G in command */
while (p->input_buf[op_start] != '#' &&
- op_start < p->input_buf_size) {
+ op_start < p->input_buf_size) {
unsigned rs_count;
unsigned rs_pos;
unsigned bytes;
- const struct user_regset_view *rsv;
- const struct user_regset *rs;
+ int rsn;
unsigned char reg_contents[MAX_REG_WIDTH];
- int rsn = gdb_remote_register_info(p, task, i,
- &rs_pos, &rs_count,
- &bytes);
- /* pr_debug ("gdb register %d => rsn %d p%u c%u b%u\n",
- i, rsn, rs_pos, rs_count, bytes); */
-
+ rsn = fetch_remote_register_info(p, task, i,
+ &rs_pos, &rs_count, &bytes);
if (rsn < 0)
break;
- /*
- * If we want to extract register data, make sure
- * we're fetching at least that much.
- */
- BUG_ON(rs_count > 0 && rs_count < bytes);
- /* Assert reg_contents size is right. */
- BUG_ON(sizeof(reg_contents) < bytes ||
- sizeof(reg_contents) < rs_count);
-
/* Remaining packet too short? */
if ((op_start + 2 * bytes + 3) < p->input_buf_size)
break;
- /*
- * 0-fill the register copy. XXX initialize
- * it from rs->get() instead?
- */
- memset(reg_contents, 0, sizeof(reg_contents));
-
- /*
- * Hex-unconvert all the bytes.
- * XXX: endianness adjust for count != bytes
- */
- for (j = 0; j < bytes; j++)
- reg_contents[j] =
- byteme(p->input_buf[op_start + 2 * j],
- p->input_buf[op_start + 2 * j + 1]);
- op_start += 2 * bytes;
-
- if (rs_count) { /* real register */
- BUG_ON(rs_count > sizeof(reg_contents));
- rsv = task_user_regset_view(task);
- BUG_ON(rsn >= rsv->n);
- rs = &rsv->regsets[rsn];
-
- /* Set register values from reg_contents[]. */
- rc = (rs->set) (task, rs, rs_pos, rs_count,
- reg_contents, NULL);
- if (rc)
- break;
- } else { /* dummy register */
- ;
- }
+ prepare_regset_set(p, reg_contents, &op_start, bytes);
+ rc = get_set_regset_view(task, rs_pos, rs_count,
+ reg_contents, rsn, true);
+ if (rc)
+ break;
}
if (p->input_buf[op_start] == '#' && rc == 0)
push_output_packet(p, "OK");
@@ -1017,59 +1029,22 @@ static void handle_gdb_command_packet(struct
gdb_connection *p,
unsigned rs_count;
unsigned rs_pos;
unsigned bytes;
- const struct user_regset_view *rsv;
- const struct user_regset *rs;
+ int rsn;
unsigned char reg_contents[MAX_REG_WIDTH];
- int rsn = gdb_remote_register_info(p, task, arg1,
- &rs_pos, &rs_count,
- &bytes);
- pr_debug("gdb register %lu => rsn %d p%u c%u b%u\n",
- arg1, rsn, rs_pos, rs_count, bytes);
-
+ rsn = fetch_remote_register_info(p, task, arg1,
+ &rs_pos, &rs_count, &bytes);
if (rsn < 0)
break;
- /*
- * If we want to extract register data, make sure
- * we're fetching at least that much.
- */
- BUG_ON(rs_count > 0 && rs_count < bytes);
- /* Assert reg_contents size is right. */
- BUG_ON(sizeof(reg_contents) < bytes ||
- sizeof(reg_contents) < rs_count);
-
/* Remaining packet too short? */
if ((op_start + 2 * bytes + 3) < p->input_buf_size)
break;
- /*
- * 0-fill the register copy.
- * XXX initialize it from rs->get() instead?
- */
- memset(reg_contents, 0, sizeof(reg_contents));
-
- /*
- * Hex-unconvert all the bytes.
- * XXX: endianness adjust for count != bytes
- */
- for (j = 0; j < bytes; j++)
- reg_contents[j] =
- byteme(p->input_buf[op_start + 2 * j],
- p->input_buf[op_start + 2 * j + 1]);
- op_start += 2 * bytes;
-
- if (rs_count) { /* real register */
- BUG_ON(rs_count > sizeof(reg_contents));
- rsv = task_user_regset_view(task);
- BUG_ON(rsn >= rsv->n);
- rs = &rsv->regsets[rsn];
-
- /* Set register values from reg_contents[]. */
- rc = (rs->set) (task, rs, rs_pos, rs_count,
- reg_contents, NULL);
- WARN_ON(rc);
- }
+ prepare_regset_set(p, reg_contents, &op_start, bytes);
+ rc = get_set_regset_view(task, rs_pos, rs_count,
+ reg_contents, rsn, true);
+ WARN_ON(rc);
if (p->input_buf[op_start] == '#' && rc == 0)
push_output_packet(p, "OK");
else
@@ -1238,7 +1213,8 @@ static int proc_gdb_open(struct inode *inode, struct file
*filp)
mutex_lock(&gdb_connections_mutex);
- /* Reject if a connection exists for the thread group
+ /*
+ * Reject if a connection exists for the thread group
* leader.
*/
list_for_each_entry(p, &gdb_connections, link) {
@@ -1519,29 +1495,27 @@ again:
} else if (p->input_buf[0] == '$') { /* command packet */
int j;
unsigned char checksum = 0;
+ unsigned char checksum2;
for (j = 1; j < p->input_buf_size - 2; j++) {
- if (p->input_buf[j] == '#') {
- unsigned char checksum2;
- checksum2 = byteme(p->input_buf[j + 1],
- p->input_buf[j + 2]);
- pr_debug("received gdb packet %.*s\n",
- j + 3, &p->input_buf[0]);
- if (checksum == checksum2) {
- push_output(p, '+');
- handle_gdb_command_packet(p,
- task);
- } else {
- push_output(p, '-');
- }
- /* Consume the whole packet. */
- p->input_buf_size -= (j + 3);
- memmove(&p->input_buf[0],
- &p->input_buf[j + 3],
- p->input_buf_size);
- break;
- } else {
+ if (p->input_buf[j] != '#') {
checksum += p->input_buf[j];
+ continue;
}
+ checksum2 = byteme(p->input_buf[j + 1],
+ p->input_buf[j + 2]);
+ pr_debug("received gdb packet %.*s\n",
+ j + 3, &p->input_buf[0]);
+ if (checksum == checksum2) {
+ push_output(p, '+');
+ handle_gdb_command_packet(p, task);
+ } else
+ push_output(p, '-');
+
+ /* Consume the whole packet. */
+ p->input_buf_size -= (j + 3);
+ memmove(&p->input_buf[0], &p->input_buf[j + 3],
+ p->input_buf_size);
+ break;
} /* End searching for end of packet */
/*
@@ -1556,8 +1530,8 @@ again:
* we'll iterate one more time in this loop.
*/
} else { /* junk character */
- printk(KERN_WARNING "Unexpected character (%x) received"
- " on /proc/%d/gdb connection.\n",
+ printk(KERN_WARNING "Unexpected character (%x) "
+ "received on /proc/%d/gdb connection.\n",
(int)p->input_buf[0], task_pid_nr(task));
/* Consume the input. */
memmove(&p->input_buf[0], &p->input_buf[1],
