pc-bios/s390-ccw: Remove panics from DASD IPL path
Remove panic-on-error from DASD IPL specific functions so that error recovery
may be possible in the future.
Functions that would previously panic now provide a return code.
Signed-off-by: Jared Rossi <jrossi@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-ID: <20241020012953.1380075-11-jrossi@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
diff --git a/pc-bios/s390-ccw/dasd-ipl.c b/pc-bios/s390-ccw/dasd-ipl.c
index ae751ad..babece9 100644
--- a/pc-bios/s390-ccw/dasd-ipl.c
+++ b/pc-bios/s390-ccw/dasd-ipl.c
@@ -111,38 +111,29 @@
ccwIplRead->count = 0x18; /* Read 0x18 bytes of data */
}
-static void run_readipl(SubChannelId schid, uint16_t cutype)
+static int run_readipl(SubChannelId schid, uint16_t cutype)
{
- if (do_cio(schid, cutype, 0x00, CCW_FMT0)) {
- panic("dasd-ipl: Failed to run Read IPL channel program\n");
- }
+ return do_cio(schid, cutype, 0x00, CCW_FMT0);
}
/*
* The architecture states that IPL1 data should consist of a psw followed by
* format-0 READ and TIC CCWs. Let's sanity check.
*/
-static void check_ipl1(void)
+static bool check_ipl1(void)
{
Ccw0 *ccwread = (Ccw0 *)0x08;
Ccw0 *ccwtic = (Ccw0 *)0x10;
- if (ccwread->cmd_code != CCW_CMD_DASD_READ ||
- ccwtic->cmd_code != CCW_CMD_TIC) {
- panic("dasd-ipl: IPL1 data invalid. Is this disk really bootable?\n");
- }
+ return (ccwread->cmd_code == CCW_CMD_DASD_READ &&
+ ccwtic->cmd_code == CCW_CMD_TIC);
}
-static void check_ipl2(uint32_t ipl2_addr)
+static bool check_ipl2(uint32_t ipl2_addr)
{
Ccw0 *ccw = u32toptr(ipl2_addr);
- if (ipl2_addr == 0x00) {
- panic("IPL2 address invalid. Is this disk really bootable?\n");
- }
- if (ccw->cmd_code == 0x00) {
- panic("IPL2 ccw data invalid. Is this disk really bootable?\n");
- }
+ return (ipl2_addr != 0x00 && ccw->cmd_code != 0x00);
}
static uint32_t read_ipl2_addr(void)
@@ -188,52 +179,67 @@
ccwSearchTic->cda = ptr2u32(ccwSearchID);
}
-static void run_ipl1(SubChannelId schid, uint16_t cutype)
+static int run_ipl1(SubChannelId schid, uint16_t cutype)
{
uint32_t startAddr = 0x08;
- if (do_cio(schid, cutype, startAddr, CCW_FMT0)) {
- panic("dasd-ipl: Failed to run IPL1 channel program\n");
- }
+ return do_cio(schid, cutype, startAddr, CCW_FMT0);
}
-static void run_ipl2(SubChannelId schid, uint16_t cutype, uint32_t addr)
+static int run_ipl2(SubChannelId schid, uint16_t cutype, uint32_t addr)
{
- if (run_dynamic_ccw_program(schid, cutype, addr)) {
- panic("dasd-ipl: Failed to run IPL2 channel program\n");
- }
+ return run_dynamic_ccw_program(schid, cutype, addr);
}
/*
* Limitations in vfio-ccw support complicate the IPL process. Details can
* be found in docs/devel/s390-dasd-ipl.rst
*/
-void dasd_ipl(SubChannelId schid, uint16_t cutype)
+int dasd_ipl(SubChannelId schid, uint16_t cutype)
{
PSWLegacy *pswl = (PSWLegacy *) 0x00;
uint32_t ipl2_addr;
/* Construct Read IPL CCW and run it to read IPL1 from boot disk */
make_readipl();
- run_readipl(schid, cutype);
+ if (run_readipl(schid, cutype)) {
+ puts("Failed to run Read IPL channel program");
+ return -EIO;
+ }
+
ipl2_addr = read_ipl2_addr();
- check_ipl1();
+
+ if (!check_ipl1()) {
+ puts("IPL1 invalid for DASD-IPL");
+ return -EINVAL;
+ }
/*
* Fixup IPL1 channel program to account for vfio-ccw limitations, then run
* it to read IPL2 channel program from boot disk.
*/
ipl1_fixup();
- run_ipl1(schid, cutype);
- check_ipl2(ipl2_addr);
+ if (run_ipl1(schid, cutype)) {
+ puts("Failed to run IPL1 channel program");
+ return -EIO;
+ }
+
+ if (!check_ipl2(ipl2_addr)) {
+ puts("IPL2 invalid for DASD-IPL");
+ return -EINVAL;
+ }
/*
* Run IPL2 channel program to read operating system code from boot disk
*/
- run_ipl2(schid, cutype, ipl2_addr);
+ if (run_ipl2(schid, cutype, ipl2_addr)) {
+ puts("Failed to run IPL2 channel program");
+ return -EIO;
+ }
/* Transfer control to the guest operating system */
pswl->mask |= PSW_MASK_EAMODE; /* Force z-mode */
pswl->addr |= PSW_MASK_BAMODE; /* ... */
jump_to_low_kernel();
+ return -1;
}
diff --git a/pc-bios/s390-ccw/dasd-ipl.h b/pc-bios/s390-ccw/dasd-ipl.h
index c394828..eb1898c 100644
--- a/pc-bios/s390-ccw/dasd-ipl.h
+++ b/pc-bios/s390-ccw/dasd-ipl.h
@@ -11,6 +11,6 @@
#ifndef DASD_IPL_H
#define DASD_IPL_H
-void dasd_ipl(SubChannelId schid, uint16_t cutype);
+int dasd_ipl(SubChannelId schid, uint16_t cutype);
#endif /* DASD_IPL_H */
