At present, the libqos/fw_cfg.c library does not support the modern DMA
interface which is required to write to the fw_cfg files. It only uses the IO
interface. Implement read and write methods based on DMA. This will enable
developers to write tests that writes to the fw_cfg file(s). The structure of
the code is taken from edk2 fw_cfg implementation. It has been tested by
writing a qtest that writes to a fw_cfg file. This test will be part of a
future patch series.
Signed-off-by: Ani Sinha <anisi...@redhat.com>
---
tests/qtest/libqos/fw_cfg.c | 191 +++++++++++++++++++++++++++++++-----
tests/qtest/libqos/fw_cfg.h | 4 +
2 files changed, 172 insertions(+), 23 deletions(-)
changelog:
v2: refactor common code into a helper.
diff --git a/tests/qtest/libqos/fw_cfg.c b/tests/qtest/libqos/fw_cfg.c
index 89f053ccac..ac4c6b73e5 100644
--- a/tests/qtest/libqos/fw_cfg.c
+++ b/tests/qtest/libqos/fw_cfg.c
@@ -17,6 +17,8 @@
#include "../libqtest.h"
#include "qemu/bswap.h"
#include "hw/nvram/fw_cfg.h"
+#include "malloc-pc.h"
+#include "libqos-malloc.h"
void qfw_cfg_select(QFWCFG *fw_cfg, uint16_t key)
{
@@ -60,6 +62,94 @@ static void mm_fw_cfg_select(QFWCFG *fw_cfg, uint16_t key)
qtest_writew(fw_cfg->qts, fw_cfg->base, key);
}
+static void
+qfw_cfg_dma_transfer(QFWCFG *fw_cfg, void *address, uint32_t length,
+ uint32_t control)
+{
+ FWCfgDmaAccess access;
+ uint32_t addr;
+ QGuestAllocator guest_malloc;
+ uint64_t guest_access_addr;
+ uint64_t gaddr;
+
+ pc_alloc_init(&guest_malloc, fw_cfg->qts, ALLOC_NO_FLAGS);
+
+ /* create a data buffer in guest memory */
+ gaddr = guest_alloc(&guest_malloc, length);
+ g_assert(gaddr);
+ qtest_bufwrite(fw_cfg->qts, gaddr, address, length);
+
+ access.address = cpu_to_be64(gaddr);
+ access.length = cpu_to_be32(length);
+ access.control = cpu_to_be32(control);
+
+ /* now create a separate buffer in guest memory for 'access' */
+ guest_access_addr = guest_alloc(&guest_malloc, sizeof(access));
+ g_assert(guest_access_addr);
+ qtest_bufwrite(fw_cfg->qts, guest_access_addr, &access, sizeof(access));
+
+ /* write lower 32 bits of address */
+ addr = cpu_to_be32((uint32_t)(uintptr_t)guest_access_addr);
+ qtest_outl(fw_cfg->qts, fw_cfg->base + 8, addr);
+
+ /* write upper 32 bits of address */
+ addr = cpu_to_be32((uint32_t)(uintptr_t)(guest_access_addr >> 32));
+ qtest_outl(fw_cfg->qts, fw_cfg->base + 4, addr);
+
+ g_assert(!(be32_to_cpu(access.control) & FW_CFG_DMA_CTL_ERROR));
+
+ guest_free(&guest_malloc, guest_access_addr);
+ guest_free(&guest_malloc, gaddr);
+ alloc_destroy(&guest_malloc);
+}
+
+static void
+qfw_cfg_write_entry(QFWCFG *fw_cfg, uint16_t key, void *buf, uint32_t len)
+{
+ qfw_cfg_select(fw_cfg, key);
+ qfw_cfg_dma_transfer(fw_cfg, buf, len, FW_CFG_DMA_CTL_WRITE);
+}
+
+static void
+qfw_cfg_read_entry(QFWCFG *fw_cfg, uint16_t key, void *buf, uint32_t len)
+{
+ qfw_cfg_select(fw_cfg, key);
+ qfw_cfg_dma_transfer(fw_cfg, buf, len, FW_CFG_DMA_CTL_READ);
+}
+
+static bool find_pdir_entry(QFWCFG *fw_cfg, const char *filename,
+ uint16_t *sel, uint32_t *size)
+{
+ unsigned char *filesbuf = NULL;
+ uint32_t count;
+ size_t dsize;
+ FWCfgFile *pdir_entry;
+ uint32_t i;
+ bool found = false;
+
+ *size = 0;
+ *sel = 0;
+
+ qfw_cfg_get(fw_cfg, FW_CFG_FILE_DIR, &count, sizeof(count));
+ count = be32_to_cpu(count);
+ dsize = sizeof(uint32_t) + count * sizeof(struct fw_cfg_file);
+ filesbuf = g_malloc(dsize);
+ g_assert(filesbuf);
+ qfw_cfg_get(fw_cfg, FW_CFG_FILE_DIR, filesbuf, dsize);
+ pdir_entry = (FWCfgFile *)(filesbuf + sizeof(uint32_t));
+ for (i = 0; i < count; ++i, ++pdir_entry) {
+ if (!strcmp(pdir_entry->name, filename)) {
+ *size = be32_to_cpu(pdir_entry->size);
+ *sel = be16_to_cpu(pdir_entry->select);
+ found = true;
+ break;
+ }
+ }
+
+ g_free(filesbuf);
+ return found;
+}
+
/*
* The caller need check the return value. When the return value is
* nonzero, it means that some bytes have been transferred.
@@ -73,37 +163,92 @@ static void mm_fw_cfg_select(QFWCFG *fw_cfg, uint16_t key)
* populated, it has received only a starting slice of the fw_cfg file.
*/
size_t qfw_cfg_get_file(QFWCFG *fw_cfg, const char *filename,
- void *data, size_t buflen)
+ void *data, size_t buflen)
{
- uint32_t count;
- uint32_t i;
- unsigned char *filesbuf = NULL;
- size_t dsize;
- FWCfgFile *pdir_entry;
size_t filesize = 0;
+ uint32_t len;
+ uint16_t sel;
- qfw_cfg_get(fw_cfg, FW_CFG_FILE_DIR, &count, sizeof(count));
- count = be32_to_cpu(count);
- dsize = sizeof(uint32_t) + count * sizeof(struct fw_cfg_file);
- filesbuf = g_malloc(dsize);
- qfw_cfg_get(fw_cfg, FW_CFG_FILE_DIR, filesbuf, dsize);
- pdir_entry = (FWCfgFile *)(filesbuf + sizeof(uint32_t));
- for (i = 0; i < count; ++i, ++pdir_entry) {
- if (!strcmp(pdir_entry->name, filename)) {
- uint32_t len = be32_to_cpu(pdir_entry->size);
- uint16_t sel = be16_to_cpu(pdir_entry->select);
- filesize = len;
- if (len > buflen) {
- len = buflen;
- }
- qfw_cfg_get(fw_cfg, sel, data, len);
- break;
+ if (find_pdir_entry(fw_cfg, filename, &sel, &len)) {
+ filesize = len;
+ if (len > buflen) {
+ len = buflen;
}
+ qfw_cfg_get(fw_cfg, sel, data, len);
}
- g_free(filesbuf);
+
return filesize;
}
+/*
+ * The caller need check the return value. When the return value is
+ * nonzero, it means that some bytes have been transferred.
+ *
+ * If the fw_cfg file in question is smaller than the allocated & passed-in
+ * buffer, then the first len bytes were read.
+ *
+ * If the fw_cfg file in question is larger than the passed-in
+ * buffer, then the return value explains how much was actually read.
+ *
+ * It is illegal to call this function if fw_cfg does not support DMA
+ * interface. The caller should ensure that DMA is supported before
+ * calling this function.
+ */
+size_t qfw_cfg_read_file(QFWCFG *fw_cfg, const char *filename,
+ void *data, size_t buflen)
+{
+ uint32_t len = 0;
+ uint16_t sel;
+ uint32_t id;
+
+ /* check if DMA is supported since we use DMA for read */
+ id = qfw_cfg_get_u32(fw_cfg, FW_CFG_ID);
+ g_assert(id & FW_CFG_VERSION_DMA);
+
+ if (find_pdir_entry(fw_cfg, filename, &sel, &len)) {
+ if (len > buflen) {
+ len = buflen;
+ }
+ qfw_cfg_read_entry(fw_cfg, sel, data, len);
+ }
+
+ return (size_t) len;
+}
+
+/*
+ * The caller need check the return value. When the return value is
+ * nonzero, it means that some bytes have been transferred.
+ *
+ * If the fw_cfg file in question is smaller than the allocated & passed-in
+ * buffer, then the buffer has been partially written.
+ *
+ * If the fw_cfg file in question is larger than the passed-in
+ * buffer, then the return value explains how much was actually written.
+ *
+ * It is illegal to call this function if fw_cfg does not support DMA
+ * interface. The caller should ensure that DMA is supported before
+ * calling this function.
+ */
+size_t qfw_cfg_write_file(QFWCFG *fw_cfg, const char *filename,
+ void *data, size_t buflen)
+{
+ uint32_t len = 0;
+ uint16_t sel;
+ uint32_t id;
+
+ /* write operation is only valid if DMA is supported */
+ id = qfw_cfg_get_u32(fw_cfg, FW_CFG_ID);
+ g_assert(id & FW_CFG_VERSION_DMA);
+
+ if (find_pdir_entry(fw_cfg, filename, &sel, &len)) {
+ if (len > buflen) {
+ len = buflen;
+ }
+ qfw_cfg_write_entry(fw_cfg, sel, data, len);
+ }
+ return (size_t) len;
+}
+
static void mm_fw_cfg_read(QFWCFG *fw_cfg, void *data, size_t len)
{
uint8_t *ptr = data;
diff --git a/tests/qtest/libqos/fw_cfg.h b/tests/qtest/libqos/fw_cfg.h
index b0456a15df..62221a9500 100644
--- a/tests/qtest/libqos/fw_cfg.h
+++ b/tests/qtest/libqos/fw_cfg.h
@@ -33,6 +33,10 @@ uint32_t qfw_cfg_get_u32(QFWCFG *fw_cfg, uint16_t key);
uint64_t qfw_cfg_get_u64(QFWCFG *fw_cfg, uint16_t key);
size_t qfw_cfg_get_file(QFWCFG *fw_cfg, const char *filename,
void *data, size_t buflen);
+size_t qfw_cfg_write_file(QFWCFG *fw_cfg, const char *filename,
+ void *data, size_t buflen);
+size_t qfw_cfg_read_file(QFWCFG *fw_cfg, const char *filename,
+ void *data, size_t buflen);
QFWCFG *mm_fw_cfg_init(QTestState *qts, uint64_t base);
void mm_fw_cfg_uninit(QFWCFG *fw_cfg);
--
2.45.2
