* [Qemu-devel] [PATCH v6 wave 1 1/4] fw-cfg: support writeable blobs
2017-01-12 18:24 [Qemu-devel] [PATCH v6 wave 1 0/4] fw-cfg: support writeable blobs and more files Laszlo Ersek
@ 2017-01-12 18:24 ` Laszlo Ersek
2017-01-12 18:24 ` [Qemu-devel] [PATCH v6 wave 1 2/4] fw-cfg: turn FW_CFG_FILE_SLOTS into a device property Laszlo Ersek
` (2 subsequent siblings)
3 siblings, 0 replies; 6+ messages in thread
From: Laszlo Ersek @ 2017-01-12 18:24 UTC (permalink / raw)
To: qemu devel list
Cc: Gabriel L. Somlo, Michael S. Tsirkin, Gerd Hoffmann,
Igor Mammedov, Michael Walle, Paolo Bonzini, Peter Maydell,
Shannon Zhao, qemu-arm
From: "Michael S. Tsirkin" <mst@redhat.com>
Useful to send guest data back to QEMU.
Changes from Laszlo Ersek <lersek@redhat.com>:
- rebase the patch from Michael Tsirkin's original postings at [1] and [2]
to the following patches:
- loader: Allow a custom AddressSpace when loading ROMs
- loader: Add AddressSpace loading support to uImages
- loader: fix handling of custom address spaces when adding ROM blobs
- reject such writes immediately that would exceed the end of the array,
rather than performing a partial write before setting the error bit: see
the (len != dma.length) condition
- document the write interface
[1] http://lists.nongnu.org/archive/html/qemu-devel/2016-02/msg04968.html
[2] http://lists.nongnu.org/archive/html/qemu-devel/2016-03/msg02735.html
Cc: "Gabriel L. Somlo" <somlo@cmu.edu>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Michael Walle <michael@walle.cc>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: Shannon Zhao <zhaoshenglong@huawei.com>
Cc: qemu-arm@nongnu.org
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Marcel Apfelbaum <marcel@redhat.com>
Acked-by: Gabriel Somlo <somlo@cmu.edu>
Tested-by: Gabriel Somlo <somlo@cmu.edu>
---
Notes:
v6:
- no changes, pick up Gabriel's A-b and T-b
v5:
- no changes, just picked up Marcel's R-b
docs/specs/fw_cfg.txt | 32 +++++++++++++++++++++++++-------
hw/lm32/lm32_hwsetup.h | 2 +-
include/hw/loader.h | 7 ++++---
include/hw/nvram/fw_cfg.h | 3 ++-
hw/arm/virt-acpi-build.c | 2 +-
hw/core/loader.c | 18 +++++++++++-------
hw/i386/acpi-build.c | 4 ++--
hw/nvram/fw_cfg.c | 37 +++++++++++++++++++++++++++++--------
8 files changed, 75 insertions(+), 30 deletions(-)
diff --git a/docs/specs/fw_cfg.txt b/docs/specs/fw_cfg.txt
index 7a5f8c7824ce..a19e2adbe1c6 100644
--- a/docs/specs/fw_cfg.txt
+++ b/docs/specs/fw_cfg.txt
@@ -33,6 +33,10 @@ the selector value is between 0x4000-0x7fff or 0xc000-0xffff.
NOTE: As of QEMU v2.4, writes to the fw_cfg data register are no
longer supported, and will be ignored (treated as no-ops)!
+NOTE: As of QEMU v2.9, writes are reinstated, but only through the DMA
+ interface (see below). Furthermore, writeability of any specific item is
+ governed independently of Bit14 in the selector key value.
+
Bit15 of the selector register indicates whether the configuration
setting is architecture specific. A value of 0 means the item is a
generic configuration item. A value of 1 means the item is specific
@@ -43,7 +47,7 @@ value between 0x8000-0xffff.
== Data Register ==
-* Read/Write (writes ignored as of QEMU v2.4)
+* Read/Write (writes ignored as of QEMU v2.4, but see the DMA interface)
* Location: platform dependent (IOport [*] or MMIO)
* Width: 8-bit (if IOport), 8/16/32/64-bit (if MMIO)
* Endianness: string-preserving
@@ -134,8 +138,8 @@ struct FWCfgFile { /* an individual file entry, 64 bytes total */
=== All Other Data Items ===
-Please consult the QEMU source for the most up-to-date and authoritative
-list of selector keys and their respective items' purpose and format.
+Please consult the QEMU source for the most up-to-date and authoritative list
+of selector keys and their respective items' purpose, format and writeability.
=== Ranges ===
@@ -144,9 +148,11 @@ items, and up to 0x4000 architecturally specific ones.
Selector Reg. Range Usage
--------------- -----------
-0x0000 - 0x3fff Generic (0x0000 - 0x3fff, RO)
+0x0000 - 0x3fff Generic (0x0000 - 0x3fff, generally RO, possibly RW through
+ the DMA interface in QEMU v2.9+)
0x4000 - 0x7fff Generic (0x0000 - 0x3fff, RW, ignored in QEMU v2.4+)
-0x8000 - 0xbfff Arch. Specific (0x0000 - 0x3fff, RO)
+0x8000 - 0xbfff Arch. Specific (0x0000 - 0x3fff, generally RO, possibly RW
+ through the DMA interface in QEMU v2.9+)
0xc000 - 0xffff Arch. Specific (0x0000 - 0x3fff, RW, ignored in v2.4+)
In practice, the number of allowed firmware configuration items is given
@@ -182,6 +188,7 @@ The "control" field has the following bits:
- Bit 1: Read
- Bit 2: Skip
- Bit 3: Select. The upper 16 bits are the selected index.
+ - Bit 4: Write
When an operation is triggered, if the "control" field has bit 3 set, the
upper 16 bits are interpreted as an index of a firmware configuration item.
@@ -191,8 +198,17 @@ If the "control" field has bit 1 set, a read operation will be performed.
"length" bytes for the current selector and offset will be copied into the
physical RAM address specified by the "address" field.
-If the "control" field has bit 2 set (and not bit 1), a skip operation will be
-performed. The offset for the current selector will be advanced "length" bytes.
+If the "control" field has bit 4 set (and not bit 1), a write operation will be
+performed. "length" bytes will be copied from the physical RAM address
+specified by the "address" field to the current selector and offset. QEMU
+prevents starting or finishing the write beyond the end of the item associated
+with the current selector (i.e., the item cannot be resized). Truncated writes
+are dropped entirely. Writes to read-only items are also rejected. All of these
+write errors set bit 0 (the error bit) in the "control" field.
+
+If the "control" field has bit 2 set (and neither bit 1 nor bit 4), a skip
+operation will be performed. The offset for the current selector will be
+advanced "length" bytes.
To check the result, read the "control" field:
error bit set -> something went wrong.
@@ -234,3 +250,5 @@ Prefix "opt/org.qemu/" is reserved for QEMU itself.
Use of names not beginning with "opt/" is potentially dangerous and
entirely unsupported. QEMU will warn if you try.
+
+All externally provided fw_cfg items are read-only to the guest.
diff --git a/hw/lm32/lm32_hwsetup.h b/hw/lm32/lm32_hwsetup.h
index 23e18784dffd..a01f6bc5dfeb 100644
--- a/hw/lm32/lm32_hwsetup.h
+++ b/hw/lm32/lm32_hwsetup.h
@@ -75,7 +75,7 @@ static inline void hwsetup_create_rom(HWSetup *hw,
hwaddr base)
{
rom_add_blob("hwsetup", hw->data, TARGET_PAGE_SIZE,
- TARGET_PAGE_SIZE, base, NULL, NULL, NULL, NULL);
+ TARGET_PAGE_SIZE, base, NULL, NULL, NULL, NULL, true);
}
static inline void hwsetup_add_u8(HWSetup *hw, uint8_t u)
diff --git a/include/hw/loader.h b/include/hw/loader.h
index 0c864cfd6046..0dbd8d6bf37a 100644
--- a/include/hw/loader.h
+++ b/include/hw/loader.h
@@ -180,7 +180,8 @@ MemoryRegion *rom_add_blob(const char *name, const void *blob, size_t len,
size_t max_len, hwaddr addr,
const char *fw_file_name,
FWCfgReadCallback fw_callback,
- void *callback_opaque, AddressSpace *as);
+ void *callback_opaque, AddressSpace *as,
+ bool read_only);
int rom_add_elf_program(const char *name, void *data, size_t datasize,
size_t romsize, hwaddr addr, AddressSpace *as);
int rom_check_and_register_reset(void);
@@ -194,7 +195,7 @@ void hmp_info_roms(Monitor *mon, const QDict *qdict);
#define rom_add_file_fixed(_f, _a, _i) \
rom_add_file(_f, NULL, _a, _i, false, NULL, NULL)
#define rom_add_blob_fixed(_f, _b, _l, _a) \
- rom_add_blob(_f, _b, _l, _l, _a, NULL, NULL, NULL, NULL)
+ rom_add_blob(_f, _b, _l, _l, _a, NULL, NULL, NULL, NULL, true)
#define rom_add_file_mr(_f, _mr, _i) \
rom_add_file(_f, NULL, 0, _i, false, _mr, NULL)
#define rom_add_file_as(_f, _as, _i) \
@@ -202,7 +203,7 @@ void hmp_info_roms(Monitor *mon, const QDict *qdict);
#define rom_add_file_fixed_as(_f, _a, _i, _as) \
rom_add_file(_f, NULL, _a, _i, false, NULL, _as)
#define rom_add_blob_fixed_as(_f, _b, _l, _a, _as) \
- rom_add_blob(_f, _b, _l, _l, _a, NULL, NULL, NULL, _as)
+ rom_add_blob(_f, _b, _l, _l, _a, NULL, NULL, NULL, _as, true)
#define PC_ROM_MIN_VGA 0xc0000
#define PC_ROM_MIN_OPTION 0xc8000
diff --git a/include/hw/nvram/fw_cfg.h b/include/hw/nvram/fw_cfg.h
index 5c27a1f0d50b..b980cbaebf43 100644
--- a/include/hw/nvram/fw_cfg.h
+++ b/include/hw/nvram/fw_cfg.h
@@ -136,6 +136,7 @@ void fw_cfg_add_file(FWCfgState *s, const char *filename, void *data,
* @callback_opaque: argument to be passed into callback function
* @data: pointer to start of item data
* @len: size of item data
+ * @read_only: is file read only
*
* Add a new NAMED fw_cfg item as a raw "blob" of the given size. The data
* referenced by the starting pointer is only linked, NOT copied, into the
@@ -151,7 +152,7 @@ void fw_cfg_add_file(FWCfgState *s, const char *filename, void *data,
*/
void fw_cfg_add_file_callback(FWCfgState *s, const char *filename,
FWCfgReadCallback callback, void *callback_opaque,
- void *data, size_t len);
+ void *data, size_t len, bool read_only);
/**
* fw_cfg_modify_file:
diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
index 085a61117378..205d6268e217 100644
--- a/hw/arm/virt-acpi-build.c
+++ b/hw/arm/virt-acpi-build.c
@@ -818,7 +818,7 @@ static MemoryRegion *acpi_add_rom_blob(AcpiBuildState *build_state,
uint64_t max_size)
{
return rom_add_blob(name, blob->data, acpi_data_len(blob), max_size, -1,
- name, virt_acpi_build_update, build_state, NULL);
+ name, virt_acpi_build_update, build_state, NULL, true);
}
static const VMStateDescription vmstate_virt_acpi_build = {
diff --git a/hw/core/loader.c b/hw/core/loader.c
index 45742494e6fd..ee5abd6eb7f4 100644
--- a/hw/core/loader.c
+++ b/hw/core/loader.c
@@ -853,7 +853,7 @@ static void fw_cfg_resized(const char *id, uint64_t length, void *host)
}
}
-static void *rom_set_mr(Rom *rom, Object *owner, const char *name)
+static void *rom_set_mr(Rom *rom, Object *owner, const char *name, bool ro)
{
void *data;
@@ -862,7 +862,7 @@ static void *rom_set_mr(Rom *rom, Object *owner, const char *name)
rom->datasize, rom->romsize,
fw_cfg_resized,
&error_fatal);
- memory_region_set_readonly(rom->mr, true);
+ memory_region_set_readonly(rom->mr, ro);
vmstate_register_ram_global(rom->mr);
data = memory_region_get_ram_ptr(rom->mr);
@@ -942,7 +942,7 @@ int rom_add_file(const char *file, const char *fw_dir,
snprintf(devpath, sizeof(devpath), "/rom@%s", fw_file_name);
if ((!option_rom || mc->option_rom_has_mr) && mc->rom_file_has_mr) {
- data = rom_set_mr(rom, OBJECT(fw_cfg), devpath);
+ data = rom_set_mr(rom, OBJECT(fw_cfg), devpath, true);
} else {
data = rom->data;
}
@@ -979,7 +979,7 @@ err:
MemoryRegion *rom_add_blob(const char *name, const void *blob, size_t len,
size_t max_len, hwaddr addr, const char *fw_file_name,
FWCfgReadCallback fw_callback, void *callback_opaque,
- AddressSpace *as)
+ AddressSpace *as, bool read_only)
{
MachineClass *mc = MACHINE_GET_CLASS(qdev_get_machine());
Rom *rom;
@@ -998,10 +998,14 @@ MemoryRegion *rom_add_blob(const char *name, const void *blob, size_t len,
char devpath[100];
void *data;
- snprintf(devpath, sizeof(devpath), "/rom@%s", fw_file_name);
+ if (read_only) {
+ snprintf(devpath, sizeof(devpath), "/rom@%s", fw_file_name);
+ } else {
+ snprintf(devpath, sizeof(devpath), "/ram@%s", fw_file_name);
+ }
if (mc->rom_file_has_mr) {
- data = rom_set_mr(rom, OBJECT(fw_cfg), devpath);
+ data = rom_set_mr(rom, OBJECT(fw_cfg), devpath, read_only);
mr = rom->mr;
} else {
data = rom->data;
@@ -1009,7 +1013,7 @@ MemoryRegion *rom_add_blob(const char *name, const void *blob, size_t len,
fw_cfg_add_file_callback(fw_cfg, fw_file_name,
fw_callback, callback_opaque,
- data, rom->datasize);
+ data, rom->datasize, read_only);
}
return mr;
}
diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
index 0c8912fd861b..a1d781ae42d8 100644
--- a/hw/i386/acpi-build.c
+++ b/hw/i386/acpi-build.c
@@ -2806,7 +2806,7 @@ static MemoryRegion *acpi_add_rom_blob(AcpiBuildState *build_state,
uint64_t max_size)
{
return rom_add_blob(name, blob->data, acpi_data_len(blob), max_size, -1,
- name, acpi_build_update, build_state, NULL);
+ name, acpi_build_update, build_state, NULL, true);
}
static const VMStateDescription vmstate_acpi_build = {
@@ -2872,7 +2872,7 @@ void acpi_setup(void)
build_state->rsdp = g_memdup(tables.rsdp->data, rsdp_size);
fw_cfg_add_file_callback(pcms->fw_cfg, ACPI_BUILD_RSDP_FILE,
acpi_build_update, build_state,
- build_state->rsdp, rsdp_size);
+ build_state->rsdp, rsdp_size, true);
build_state->rsdp_mr = NULL;
} else {
build_state->rsdp = NULL;
diff --git a/hw/nvram/fw_cfg.c b/hw/nvram/fw_cfg.c
index 3ebecb22606a..e0145c11a19b 100644
--- a/hw/nvram/fw_cfg.c
+++ b/hw/nvram/fw_cfg.c
@@ -54,11 +54,13 @@
#define FW_CFG_DMA_CTL_READ 0x02
#define FW_CFG_DMA_CTL_SKIP 0x04
#define FW_CFG_DMA_CTL_SELECT 0x08
+#define FW_CFG_DMA_CTL_WRITE 0x10
#define FW_CFG_DMA_SIGNATURE 0x51454d5520434647ULL /* "QEMU CFG" */
typedef struct FWCfgEntry {
uint32_t len;
+ bool allow_write;
uint8_t *data;
void *callback_opaque;
FWCfgReadCallback read_callback;
@@ -326,7 +328,7 @@ static void fw_cfg_dma_transfer(FWCfgState *s)
FWCfgDmaAccess dma;
int arch;
FWCfgEntry *e;
- int read;
+ int read = 0, write = 0;
dma_addr_t dma_addr;
/* Reset the address before the next access */
@@ -353,8 +355,13 @@ static void fw_cfg_dma_transfer(FWCfgState *s)
if (dma.control & FW_CFG_DMA_CTL_READ) {
read = 1;
+ write = 0;
+ } else if (dma.control & FW_CFG_DMA_CTL_WRITE) {
+ read = 0;
+ write = 1;
} else if (dma.control & FW_CFG_DMA_CTL_SKIP) {
read = 0;
+ write = 0;
} else {
dma.length = 0;
}
@@ -374,7 +381,9 @@ static void fw_cfg_dma_transfer(FWCfgState *s)
dma.control |= FW_CFG_DMA_CTL_ERROR;
}
}
-
+ if (write) {
+ dma.control |= FW_CFG_DMA_CTL_ERROR;
+ }
} else {
if (dma.length <= (e->len - s->cur_offset)) {
len = dma.length;
@@ -391,6 +400,14 @@ static void fw_cfg_dma_transfer(FWCfgState *s)
dma.control |= FW_CFG_DMA_CTL_ERROR;
}
}
+ if (write) {
+ if (!e->allow_write ||
+ len != dma.length ||
+ dma_memory_read(s->dma_as, dma.address,
+ &e->data[s->cur_offset], len)) {
+ dma.control |= FW_CFG_DMA_CTL_ERROR;
+ }
+ }
s->cur_offset += len;
}
@@ -586,7 +603,8 @@ static const VMStateDescription vmstate_fw_cfg = {
static void fw_cfg_add_bytes_read_callback(FWCfgState *s, uint16_t key,
FWCfgReadCallback callback,
void *callback_opaque,
- void *data, size_t len)
+ void *data, size_t len,
+ bool read_only)
{
int arch = !!(key & FW_CFG_ARCH_LOCAL);
@@ -599,6 +617,7 @@ static void fw_cfg_add_bytes_read_callback(FWCfgState *s, uint16_t key,
s->entries[arch][key].len = (uint32_t)len;
s->entries[arch][key].read_callback = callback;
s->entries[arch][key].callback_opaque = callback_opaque;
+ s->entries[arch][key].allow_write = !read_only;
}
static void *fw_cfg_modify_bytes_read(FWCfgState *s, uint16_t key,
@@ -616,13 +635,14 @@ static void *fw_cfg_modify_bytes_read(FWCfgState *s, uint16_t key,
s->entries[arch][key].data = data;
s->entries[arch][key].len = len;
s->entries[arch][key].callback_opaque = NULL;
+ s->entries[arch][key].allow_write = false;
return ptr;
}
void fw_cfg_add_bytes(FWCfgState *s, uint16_t key, void *data, size_t len)
{
- fw_cfg_add_bytes_read_callback(s, key, NULL, NULL, data, len);
+ fw_cfg_add_bytes_read_callback(s, key, NULL, NULL, data, len, true);
}
void fw_cfg_add_string(FWCfgState *s, uint16_t key, const char *value)
@@ -749,7 +769,7 @@ static int get_fw_cfg_order(FWCfgState *s, const char *name)
void fw_cfg_add_file_callback(FWCfgState *s, const char *filename,
FWCfgReadCallback callback, void *callback_opaque,
- void *data, size_t len)
+ void *data, size_t len, bool read_only)
{
int i, index, count;
size_t dsize;
@@ -811,7 +831,8 @@ void fw_cfg_add_file_callback(FWCfgState *s, const char *filename,
}
fw_cfg_add_bytes_read_callback(s, FW_CFG_FILE_FIRST + index,
- callback, callback_opaque, data, len);
+ callback, callback_opaque, data, len,
+ read_only);
s->files->f[index].size = cpu_to_be32(len);
s->files->f[index].select = cpu_to_be16(FW_CFG_FILE_FIRST + index);
@@ -824,7 +845,7 @@ void fw_cfg_add_file_callback(FWCfgState *s, const char *filename,
void fw_cfg_add_file(FWCfgState *s, const char *filename,
void *data, size_t len)
{
- fw_cfg_add_file_callback(s, filename, NULL, NULL, data, len);
+ fw_cfg_add_file_callback(s, filename, NULL, NULL, data, len, true);
}
void *fw_cfg_modify_file(FWCfgState *s, const char *filename,
@@ -847,7 +868,7 @@ void *fw_cfg_modify_file(FWCfgState *s, const char *filename,
}
}
/* add new one */
- fw_cfg_add_file_callback(s, filename, NULL, NULL, data, len);
+ fw_cfg_add_file_callback(s, filename, NULL, NULL, data, len, true);
return NULL;
}
--
2.9.3
^ permalink raw reply related [flat|nested] 6+ messages in thread* [Qemu-devel] [PATCH v6 wave 1 2/4] fw-cfg: turn FW_CFG_FILE_SLOTS into a device property
2017-01-12 18:24 [Qemu-devel] [PATCH v6 wave 1 0/4] fw-cfg: support writeable blobs and more files Laszlo Ersek
2017-01-12 18:24 ` [Qemu-devel] [PATCH v6 wave 1 1/4] fw-cfg: support writeable blobs Laszlo Ersek
@ 2017-01-12 18:24 ` Laszlo Ersek
2017-01-12 18:24 ` [Qemu-devel] [PATCH v6 wave 1 3/4] pc: Add 2.9 machine-types Laszlo Ersek
2017-01-12 18:24 ` [Qemu-devel] [PATCH v6 wave 1 4/4] fw-cfg: bump "x-file-slots" to 0x20 for 2.9+ machine types Laszlo Ersek
3 siblings, 0 replies; 6+ messages in thread
From: Laszlo Ersek @ 2017-01-12 18:24 UTC (permalink / raw)
To: qemu devel list
Cc: Gabriel L. Somlo, Michael S. Tsirkin, Gerd Hoffmann,
Igor Mammedov, Paolo Bonzini
We'd like to raise the value of FW_CFG_FILE_SLOTS. Doing it naively could
lead to problems with backward migration: a more recent QEMU (running an
older machine type) would allow the guest, in fw_cfg_select(), to select a
high key value that is unavailable in the same machine type implemented by
the older (target) QEMU. On the target host, fw_cfg_data_read() for
example could dereference nonexistent entries.
As first step, size the FWCfgState.entries[*] and FWCfgState.entry_order
arrays dynamically. All three array sizes will be influenced by the new
field FWCfgState.file_slots (and matching device property).
Make the following changes:
- Replace the FW_CFG_FILE_SLOTS macro with FW_CFG_FILE_SLOTS_MIN (minimum
count of fw_cfg file slots) in the header file. The value remains 0x10.
- Replace all uses of FW_CFG_FILE_SLOTS with a helper function called
fw_cfg_file_slots(), returning the new property.
- Eliminate the macro FW_CFG_MAX_ENTRY, and replace all its uses with a
helper function called fw_cfg_max_entry().
- In the MMIO- and IO-mapped realize functions both, allocate all three
arrays dynamically, based on the new property.
- The new property defaults to FW_CFG_FILE_SLOTS_MIN. This is going to be
customized in the following patches.
Cc: "Gabriel L. Somlo" <somlo@cmu.edu>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Acked-by: Gabriel Somlo <somlo@cmu.edu>
Tested-by: Gabriel Somlo <somlo@cmu.edu>
---
Notes:
v6:
- rename the "file_slots" property to "x-file-slots" [Eduardo, Michael]
- pick up Gabriel's A-b and T-b
v5:
- change the type of "FWCfgState.file_slots" to "uint16_t" [Igor]
- same for the retval of the trivial wrapper function
fw_cfg_file_slots(), and for the corresponding "file_slots" device
properties
- preserve the fw_cfg_file_slots() wrapper func (Igor was okay with it
in the end)
- rename FW_CFG_FILE_SLOTS_TRAD to FW_CFG_FILE_SLOTS_MIN
- Remove explicit qdev_prop_set_uint32() calls from fw_cfg_init_io_dma()
and fw_cfg_init_mem_wide(), but set the property default to
FW_CFG_FILE_SLOTS_MIN (0x10). This is the main change relative to v4;
the idea is that per-board opt-in shouldn't be necessary for an
increased file_slots count *in addition to* selecting a 2.9 machine
type. [Igor]
- delay the now-unused FW_CFG_FILE_SLOTS_DFLT macro to a later patch
v4:
- I know that upstream doesn't care about backward migration, but some
downstreams might.
docs/specs/fw_cfg.txt | 2 +-
include/hw/nvram/fw_cfg_keys.h | 3 +-
hw/nvram/fw_cfg.c | 71 +++++++++++++++++++++++++++++++++++++-----
3 files changed, 65 insertions(+), 11 deletions(-)
diff --git a/docs/specs/fw_cfg.txt b/docs/specs/fw_cfg.txt
index a19e2adbe1c6..9373bbc64743 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/include/hw/nvram/fw_cfg_keys.h b/include/hw/nvram/fw_cfg_keys.h
index 0f3e871884c0..b6919451f5bd 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
diff --git a/hw/nvram/fw_cfg.c b/hw/nvram/fw_cfg.c
index e0145c11a19b..bf75ef71d57e 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);
--
2.9.3
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