| Message ID | 20250107145138.157696-1-anisinha@redhat.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] tests/qtest/libqos: add DMA support for writing and reading fw_cfg files | expand |
> On 7 Jan 2025, at 8:21 PM, Ani Sinha <anisinha@redhat.com> wrote: > > 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 <anisinha@redhat.com> Please disregard this patch for now. I was under the false impression that this was working. More testing revealed that there might still be some issues with this patch. Apologies for this. > --- > 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 >
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);
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 <anisinha@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.