| Message ID | 20250108125751.199929-1-anisinha@redhat.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [v3] tests/qtest/libqos: add DMA support for writing and reading fw_cfg files | expand |
On Wed, Jan 08, 2025 at 06:27:50PM +0530, Ani Sinha 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> > --- > tests/qtest/libqos/fw_cfg.c | 204 ++++++++++++++++++++++++++++++++---- > tests/qtest/libqos/fw_cfg.h | 5 + > 2 files changed, 186 insertions(+), 23 deletions(-) > +static bool > +find_pdir_entry(QFWCFG *fw_cfg, const char *filename, > + uint16_t *sel, uint32_t *size) > +{ > + unsigned char *filesbuf = NULL; Use g_autofree here instead of later g_free. > + 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)); I'm not familiar with fwcfg data format, but I'm wondering what the initial 'uint32_t' data field is that you're skipping over, and whether its value should be validated before this loop ? > + 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 +168,100 @@ 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; > } I'd recommend refactoring of existnig code, be a separate commit from the newly added functionality. > > +/* > + * 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. > + * > + * Passed QOSState pointer qs must be initialized. qs->alloc must also be > + * properly initialized. > + */ > +size_t qfw_cfg_read_file(QFWCFG *fw_cfg, QOSState *qs, const char *filename, > + void *data, size_t buflen) > +{ > + uint32_t len = 0; > + uint16_t sel; > + uint32_t id; > + > + g_assert(qs); > + /* 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, qs, sel, data, len); > + } > + > + return (size_t) len; The size_t cast is redundant, since we know sizeof(size_t) will be >= sizeof(uint32_t) on all platforms > +} > + > +/* > + * 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. > + * > + * Passed QOSState pointer qs must be initialized. qs->alloc must also be > + * properly initialized. > + */ > +size_t qfw_cfg_write_file(QFWCFG *fw_cfg, QOSState *qs, const char *filename, > + void *data, size_t buflen) > +{ > + uint32_t len = 0; > + uint16_t sel; > + uint32_t id; > + > + g_assert(qs); > + /* 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, qs, sel, data, len); > + } > + return (size_t) len; Another redundant cast With regards, Daniel
> On 8 Jan 2025, at 6:38 PM, Daniel P. Berrangé <berrange@redhat.com> wrote: > > On Wed, Jan 08, 2025 at 06:27:50PM +0530, Ani Sinha 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> >> --- >> tests/qtest/libqos/fw_cfg.c | 204 ++++++++++++++++++++++++++++++++---- >> tests/qtest/libqos/fw_cfg.h | 5 + >> 2 files changed, 186 insertions(+), 23 deletions(-) > >> +static bool >> +find_pdir_entry(QFWCFG *fw_cfg, const char *filename, >> + uint16_t *sel, uint32_t *size) >> +{ >> + unsigned char *filesbuf = NULL; > > Use g_autofree here instead of later g_free. OK will send just a refactoring patch with this change. > >> + 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)); > > I'm not familiar with fwcfg data format, but I'm wondering > what the initial 'uint32_t' data field is that you're skipping > over, and whether its value should be validated before this > loop ? This part I left as is from previous code. From https://www.qemu.org/docs/master/specs/fw_cfg.html struct FWCfgFiles { /* the entire file directory fw_cfg item */ uint32_t count; /* number of entries, in big-endian format */ struct FWCfgFile f[]; /* array of file entries, see below */ }; struct FWCfgFile { /* an individual file entry, 64 bytes total */ uint32_t size; /* size of referenced fw_cfg item, big-endian */ uint16_t select; /* selector key of fw_cfg item, big-endian */ uint16_t reserved; char name[56]; /* fw_cfg item name, NUL-terminated ascii */ }; So the code first reads the count and then allocates ‘count' entries for ‘count' files. > >> + 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 +168,100 @@ 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; >> } > > I'd recommend refactoring of existnig code, be a separate commit > from the newly added functionality. Yes will do that. > >> >> +/* >> + * 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. >> + * >> + * Passed QOSState pointer qs must be initialized. qs->alloc must also be >> + * properly initialized. >> + */ >> +size_t qfw_cfg_read_file(QFWCFG *fw_cfg, QOSState *qs, const char *filename, >> + void *data, size_t buflen) >> +{ >> + uint32_t len = 0; >> + uint16_t sel; >> + uint32_t id; >> + >> + g_assert(qs); >> + /* 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, qs, sel, data, len); >> + } >> + >> + return (size_t) len; > > The size_t cast is redundant, since we know sizeof(size_t) > will be >= sizeof(uint32_t) on all platforms > >> +} >> + >> +/* >> + * 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. >> + * >> + * Passed QOSState pointer qs must be initialized. qs->alloc must also be >> + * properly initialized. >> + */ >> +size_t qfw_cfg_write_file(QFWCFG *fw_cfg, QOSState *qs, const char *filename, >> + void *data, size_t buflen) >> +{ >> + uint32_t len = 0; >> + uint16_t sel; >> + uint32_t id; >> + >> + g_assert(qs); >> + /* 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, qs, sel, data, len); >> + } >> + return (size_t) len; > > Another redundant cast > > > With regards, > Daniel > -- > |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| > |: https://libvirt.org -o- https://fstop138.berrange.com :| > |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|
On Wed, Jan 08, 2025 at 06:47:25PM +0530, Ani Sinha wrote: > > > > On 8 Jan 2025, at 6:38 PM, Daniel P. Berrangé <berrange@redhat.com> wrote: > > > > On Wed, Jan 08, 2025 at 06:27:50PM +0530, Ani Sinha 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> > >> --- > >> tests/qtest/libqos/fw_cfg.c | 204 ++++++++++++++++++++++++++++++++---- > >> tests/qtest/libqos/fw_cfg.h | 5 + > >> 2 files changed, 186 insertions(+), 23 deletions(-) > > > >> +static bool > >> +find_pdir_entry(QFWCFG *fw_cfg, const char *filename, > >> + uint16_t *sel, uint32_t *size) > >> +{ > >> + unsigned char *filesbuf = NULL; > > > > Use g_autofree here instead of later g_free. > > OK will send just a refactoring patch with this change. > > > > >> + 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)); > > > > I'm not familiar with fwcfg data format, but I'm wondering > > what the initial 'uint32_t' data field is that you're skipping > > over, and whether its value should be validated before this > > loop ? > > This part I left as is from previous code. From https://www.qemu.org/docs/master/specs/fw_cfg.html > > struct FWCfgFiles { /* the entire file directory fw_cfg item */ > uint32_t count; /* number of entries, in big-endian format */ > struct FWCfgFile f[]; /* array of file entries, see below */ > }; > > struct FWCfgFile { /* an individual file entry, 64 bytes total */ > uint32_t size; /* size of referenced fw_cfg item, big-endian */ > uint16_t select; /* selector key of fw_cfg item, big-endian */ > uint16_t reserved; > char name[56]; /* fw_cfg item name, NUL-terminated ascii */ > }; > > So the code first reads the count and then allocates ‘count' entries for ‘count' files. Ah right, so the first qfw_cfg_get already read count, and the second qfw_cfg_get reads it again, followed by the entries, so we can ignore that first field. With regards, Daniel
diff --git a/tests/qtest/libqos/fw_cfg.c b/tests/qtest/libqos/fw_cfg.c index 89f053ccac..02d16b098c 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 +62,99 @@ 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, QOSState *qs, void *address, + uint32_t length, uint32_t control) +{ + FWCfgDmaAccess access; + uint32_t addr; + uint64_t guest_access_addr; + uint64_t gaddr; + + /* create a data buffer in guest memory */ + gaddr = guest_alloc(&qs->alloc, length); + g_assert(gaddr); + + if (control & FW_CFG_DMA_CTL_WRITE) { + 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(&qs->alloc, 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)); + + if (control & FW_CFG_DMA_CTL_READ) { + qtest_bufread(fw_cfg->qts, gaddr, address, length); + } + + guest_free(&qs->alloc, guest_access_addr); + guest_free(&qs->alloc, gaddr); +} + +static void +qfw_cfg_write_entry(QFWCFG *fw_cfg, QOSState *qs, uint16_t key, + void *buf, uint32_t len) +{ + qfw_cfg_select(fw_cfg, key); + qfw_cfg_dma_transfer(fw_cfg, qs, buf, len, FW_CFG_DMA_CTL_WRITE); +} + +static void +qfw_cfg_read_entry(QFWCFG *fw_cfg, QOSState *qs, uint16_t key, + void *buf, uint32_t len) +{ + qfw_cfg_select(fw_cfg, key); + qfw_cfg_dma_transfer(fw_cfg, qs, 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 +168,100 @@ 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. + * + * Passed QOSState pointer qs must be initialized. qs->alloc must also be + * properly initialized. + */ +size_t qfw_cfg_read_file(QFWCFG *fw_cfg, QOSState *qs, const char *filename, + void *data, size_t buflen) +{ + uint32_t len = 0; + uint16_t sel; + uint32_t id; + + g_assert(qs); + /* 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, qs, 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. + * + * Passed QOSState pointer qs must be initialized. qs->alloc must also be + * properly initialized. + */ +size_t qfw_cfg_write_file(QFWCFG *fw_cfg, QOSState *qs, const char *filename, + void *data, size_t buflen) +{ + uint32_t len = 0; + uint16_t sel; + uint32_t id; + + g_assert(qs); + /* 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, qs, 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..63c1ac59d6 100644 --- a/tests/qtest/libqos/fw_cfg.h +++ b/tests/qtest/libqos/fw_cfg.h @@ -14,6 +14,7 @@ #define LIBQOS_FW_CFG_H #include "../libqtest.h" +#include "libqos.h" typedef struct QFWCFG QFWCFG; @@ -33,6 +34,10 @@ 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, QOSState *qs, const char *filename, + void *data, size_t buflen); +size_t qfw_cfg_read_file(QFWCFG *fw_cfg, QOSState *qs, 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 | 204 ++++++++++++++++++++++++++++++++---- tests/qtest/libqos/fw_cfg.h | 5 + 2 files changed, 186 insertions(+), 23 deletions(-) changelog: v3: fix bugs and code reorg. More testing to make sure this actually works. v2: refactor common code into a helper.