diff options
| -rw-r--r-- | docs/specs/fw_cfg.txt | 2 | ||||
| -rw-r--r-- | hw/nvram/fw_cfg.c | 71 | ||||
| -rw-r--r-- | include/hw/nvram/fw_cfg_keys.h | 3 |
3 files changed, 65 insertions, 11 deletions
diff --git a/docs/specs/fw_cfg.txt b/docs/specs/fw_cfg.txt index a19e2adbe1..9373bbc647 100644 --- a/docs/specs/fw_cfg.txt +++ b/docs/specs/fw_cfg.txt @@ -156,7 +156,7 @@ Selector Reg. Range Usage 0xc000 - 0xffff Arch. Specific (0x0000 - 0x3fff, RW, ignored in v2.4+) In practice, the number of allowed firmware configuration items is given -by the value of FW_CFG_MAX_ENTRY (see fw_cfg.h). +by the value (FW_CFG_FILE_FIRST + FW_CFG_FILE_SLOTS_MIN) (see fw_cfg.h). = Guest-side DMA Interface = diff --git a/hw/nvram/fw_cfg.c b/hw/nvram/fw_cfg.c index e0145c11a1..bf75ef71d5 100644 --- a/hw/nvram/fw_cfg.c +++ b/hw/nvram/fw_cfg.c @@ -33,6 +33,7 @@ #include "qemu/error-report.h" #include "qemu/config-file.h" #include "qemu/cutils.h" +#include "qapi/error.h" #define FW_CFG_NAME "fw_cfg" #define FW_CFG_PATH "/machine/" FW_CFG_NAME @@ -71,8 +72,9 @@ struct FWCfgState { SysBusDevice parent_obj; /*< public >*/ - FWCfgEntry entries[2][FW_CFG_MAX_ENTRY]; - int entry_order[FW_CFG_MAX_ENTRY]; + uint16_t file_slots; + FWCfgEntry *entries[2]; + int *entry_order; FWCfgFiles *files; uint16_t cur_entry; uint32_t cur_offset; @@ -257,13 +259,24 @@ static void fw_cfg_write(FWCfgState *s, uint8_t value) /* nothing, write support removed in QEMU v2.4+ */ } +static inline uint16_t fw_cfg_file_slots(const FWCfgState *s) +{ + return s->file_slots; +} + +/* Note: this function returns an exclusive limit. */ +static inline uint32_t fw_cfg_max_entry(const FWCfgState *s) +{ + return FW_CFG_FILE_FIRST + fw_cfg_file_slots(s); +} + static int fw_cfg_select(FWCfgState *s, uint16_t key) { int arch, ret; FWCfgEntry *e; s->cur_offset = 0; - if ((key & FW_CFG_ENTRY_MASK) >= FW_CFG_MAX_ENTRY) { + if ((key & FW_CFG_ENTRY_MASK) >= fw_cfg_max_entry(s)) { s->cur_entry = FW_CFG_INVALID; ret = 0; } else { @@ -610,7 +623,7 @@ static void fw_cfg_add_bytes_read_callback(FWCfgState *s, uint16_t key, key &= FW_CFG_ENTRY_MASK; - assert(key < FW_CFG_MAX_ENTRY && len < UINT32_MAX); + assert(key < fw_cfg_max_entry(s) && len < UINT32_MAX); assert(s->entries[arch][key].data == NULL); /* avoid key conflict */ s->entries[arch][key].data = data; @@ -628,7 +641,7 @@ static void *fw_cfg_modify_bytes_read(FWCfgState *s, uint16_t key, key &= FW_CFG_ENTRY_MASK; - assert(key < FW_CFG_MAX_ENTRY && len < UINT32_MAX); + assert(key < fw_cfg_max_entry(s) && len < UINT32_MAX); /* return the old data to the function caller, avoid memory leak */ ptr = s->entries[arch][key].data; @@ -777,13 +790,13 @@ void fw_cfg_add_file_callback(FWCfgState *s, const char *filename, int order = 0; if (!s->files) { - dsize = sizeof(uint32_t) + sizeof(FWCfgFile) * FW_CFG_FILE_SLOTS; + dsize = sizeof(uint32_t) + sizeof(FWCfgFile) * fw_cfg_file_slots(s); s->files = g_malloc0(dsize); fw_cfg_add_bytes(s, FW_CFG_FILE_DIR, s->files, dsize); } count = be32_to_cpu(s->files->count); - assert(count < FW_CFG_FILE_SLOTS); + assert(count < fw_cfg_file_slots(s)); /* Find the insertion point. */ if (mc->legacy_fw_cfg_order) { @@ -857,7 +870,7 @@ void *fw_cfg_modify_file(FWCfgState *s, const char *filename, assert(s->files); index = be32_to_cpu(s->files->count); - assert(index < FW_CFG_FILE_SLOTS); + assert(index < fw_cfg_file_slots(s)); for (i = 0; i < index; i++) { if (strcmp(filename, s->files->f[i].name) == 0) { @@ -1014,12 +1027,38 @@ static const TypeInfo fw_cfg_info = { .class_init = fw_cfg_class_init, }; +static void fw_cfg_file_slots_allocate(FWCfgState *s, Error **errp) +{ + uint16_t file_slots_max; + + if (fw_cfg_file_slots(s) < FW_CFG_FILE_SLOTS_MIN) { + error_setg(errp, "\"file_slots\" must be at least 0x%x", + FW_CFG_FILE_SLOTS_MIN); + return; + } + + /* (UINT16_MAX & FW_CFG_ENTRY_MASK) is the highest inclusive selector value + * that we permit. The actual (exclusive) value coming from the + * configuration is (FW_CFG_FILE_FIRST + fw_cfg_file_slots(s)). */ + file_slots_max = (UINT16_MAX & FW_CFG_ENTRY_MASK) - FW_CFG_FILE_FIRST + 1; + if (fw_cfg_file_slots(s) > file_slots_max) { + error_setg(errp, "\"file_slots\" must not exceed 0x%" PRIx16, + file_slots_max); + return; + } + + s->entries[0] = g_new0(FWCfgEntry, fw_cfg_max_entry(s)); + s->entries[1] = g_new0(FWCfgEntry, fw_cfg_max_entry(s)); + s->entry_order = g_new0(int, fw_cfg_max_entry(s)); +} static Property fw_cfg_io_properties[] = { DEFINE_PROP_UINT32("iobase", FWCfgIoState, iobase, -1), DEFINE_PROP_UINT32("dma_iobase", FWCfgIoState, dma_iobase, -1), DEFINE_PROP_BOOL("dma_enabled", FWCfgIoState, parent_obj.dma_enabled, true), + DEFINE_PROP_UINT16("x-file-slots", FWCfgIoState, parent_obj.file_slots, + FW_CFG_FILE_SLOTS_MIN), DEFINE_PROP_END_OF_LIST(), }; @@ -1027,6 +1066,13 @@ static void fw_cfg_io_realize(DeviceState *dev, Error **errp) { FWCfgIoState *s = FW_CFG_IO(dev); SysBusDevice *sbd = SYS_BUS_DEVICE(dev); + Error *local_err = NULL; + + fw_cfg_file_slots_allocate(FW_CFG(s), &local_err); + if (local_err) { + error_propagate(errp, local_err); + return; + } /* when using port i/o, the 8-bit data register ALWAYS overlaps * with half of the 16-bit control register. Hence, the total size @@ -1063,6 +1109,8 @@ static Property fw_cfg_mem_properties[] = { DEFINE_PROP_UINT32("data_width", FWCfgMemState, data_width, -1), DEFINE_PROP_BOOL("dma_enabled", FWCfgMemState, parent_obj.dma_enabled, true), + DEFINE_PROP_UINT16("x-file-slots", FWCfgMemState, parent_obj.file_slots, + FW_CFG_FILE_SLOTS_MIN), DEFINE_PROP_END_OF_LIST(), }; @@ -1071,6 +1119,13 @@ static void fw_cfg_mem_realize(DeviceState *dev, Error **errp) FWCfgMemState *s = FW_CFG_MEM(dev); SysBusDevice *sbd = SYS_BUS_DEVICE(dev); const MemoryRegionOps *data_ops = &fw_cfg_data_mem_ops; + Error *local_err = NULL; + + fw_cfg_file_slots_allocate(FW_CFG(s), &local_err); + if (local_err) { + error_propagate(errp, local_err); + return; + } memory_region_init_io(&s->ctl_iomem, OBJECT(s), &fw_cfg_ctl_mem_ops, FW_CFG(s), "fwcfg.ctl", FW_CFG_CTL_SIZE); diff --git a/include/hw/nvram/fw_cfg_keys.h b/include/hw/nvram/fw_cfg_keys.h index 0f3e871884..b6919451f5 100644 --- a/include/hw/nvram/fw_cfg_keys.h +++ b/include/hw/nvram/fw_cfg_keys.h @@ -29,8 +29,7 @@ #define FW_CFG_FILE_DIR 0x19 #define FW_CFG_FILE_FIRST 0x20 -#define FW_CFG_FILE_SLOTS 0x10 -#define FW_CFG_MAX_ENTRY (FW_CFG_FILE_FIRST + FW_CFG_FILE_SLOTS) +#define FW_CFG_FILE_SLOTS_MIN 0x10 #define FW_CFG_WRITE_CHANNEL 0x4000 #define FW_CFG_ARCH_LOCAL 0x8000 |