| Message ID | 20170111173457.30455-3-lersek@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Jan 11, 2017 at 06:34:55PM +0100, Laszlo Ersek wrote: [...] > 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("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) I'm not sure what is more important here: following the QOM property name convention using "-" instead of "_", or being consistent with the other existing properties. In either case, we could add a "x-" prefix to indicate it is not supposed to be configured directly by the user. [...] > @@ -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("file_slots", FWCfgMemState, parent_obj.file_slots, > + FW_CFG_FILE_SLOTS_MIN), It looks like you can add the property to the TYPE_FW_CFG parent class instead of duplicating it on the subclasses. The existing "dma_enabled" property could be moved there as well.
On Wed, Jan 11, 2017 at 06:34:55PM +0100, Laszlo Ersek wrote: > 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 (and device property) FWCfgState.file_slots. > > 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> > --- > > Notes: > 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..313d943ebd27 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("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("file_slots", FWCfgMemState, parent_obj.file_slots, > + FW_CFG_FILE_SLOTS_MIN), I think it's an internal compatibility thing, so we want to call it x-file-slots instead. > 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 >
On 01/12/17 14:10, Eduardo Habkost wrote: > On Wed, Jan 11, 2017 at 06:34:55PM +0100, Laszlo Ersek wrote: > [...] >> 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("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) > > I'm not sure what is more important here: following the QOM > property name convention using "-" instead of "_", or being > consistent with the other existing properties. Right, when working with the compat settings, I saw both schemes. I couldn't decide. I figured I'd stick with the underscore seen with "dma_enabled". > > In either case, we could add a "x-" prefix to indicate it is not > supposed to be configured directly by the user. I thought "x-" meant "experimental"; i.e., the property could be changed or could go away at any moment. That's a slightly different meaning than "not meant for users". BTW I think the same (== not meant for the user) applies to a number of other properties (dma_enabled is one of them, but other devices have this kind too); do we consistently call them x-*? > > [...] >> @@ -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("file_slots", FWCfgMemState, parent_obj.file_slots, >> + FW_CFG_FILE_SLOTS_MIN), > > It looks like you can add the property to the TYPE_FW_CFG parent > class instead of duplicating it on the subclasses. The existing > "dma_enabled" property could be moved there as well. I would prefer if someone could pick up that task, separately. The idea crossed my mind when I was working on the common base class, originally, wrt. dma_enabled. I vaguely remember that there was some problem with moving up the property. Ultimately the reviewers didn't expect me, or suggest, to move it up, hence the current status. I think it's out of scope for this series. If you (or someone else) can do it, I agree it would be an improvement, but I'd rather learn the method from someone else's patch than experiment with it myself. If there's a consensus on the x- prefix and/or the underscore/hyphen question, I'm happy to send a v6 with those changes. Thanks, Laszlo
On 01/12/17 15:29, Michael S. Tsirkin wrote: > On Wed, Jan 11, 2017 at 06:34:55PM +0100, Laszlo Ersek wrote: >> 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 (and device property) FWCfgState.file_slots. >> >> 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> >> --- >> >> Notes: >> 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..313d943ebd27 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("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("file_slots", FWCfgMemState, parent_obj.file_slots, >> + FW_CFG_FILE_SLOTS_MIN), > > I think it's an internal compatibility thing, so we want to call it > x-file-slots instead. Alright, Eduardo suggested the same independently; I will send a v6 with this update. Thanks! Laszlo > > >> 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 >>
On Thu, Jan 12, 2017 at 05:30:42PM +0100, Laszlo Ersek wrote: > On 01/12/17 14:10, Eduardo Habkost wrote: > > On Wed, Jan 11, 2017 at 06:34:55PM +0100, Laszlo Ersek wrote: > > [...] > >> 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("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) > > > > I'm not sure what is more important here: following the QOM > > property name convention using "-" instead of "_", or being > > consistent with the other existing properties. > > Right, when working with the compat settings, I saw both schemes. I > couldn't decide. I figured I'd stick with the underscore seen with > "dma_enabled". > > > > > In either case, we could add a "x-" prefix to indicate it is not > > supposed to be configured directly by the user. > > I thought "x-" meant "experimental"; i.e., the property could be changed > or could go away at any moment. That's a slightly different meaning than > "not meant for users". That's true: it means the property could be changed or go away. And that's the only mechanism we have to indicate that users shouldn't rely on the property being always available on the command-line in future versions. (Yes, this should be better documented. We found out very recently that people have very different expectations about what QOM properties should be used for, so we are still figuring out what should be the best practices and didn't write everything down yet.) > > BTW I think the same (== not meant for the user) applies to a number of > other properties (dma_enabled is one of them, but other devices have > this kind too); do we consistently call them x-*? We don't, but that's because we haven't been paying attention to that until recently. Renaming existing properties is possible, but risks breaking existing software and scripts. > > > > > [...] > >> @@ -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("file_slots", FWCfgMemState, parent_obj.file_slots, > >> + FW_CFG_FILE_SLOTS_MIN), > > > > It looks like you can add the property to the TYPE_FW_CFG parent > > class instead of duplicating it on the subclasses. The existing > > "dma_enabled" property could be moved there as well. > > I would prefer if someone could pick up that task, separately. > > The idea crossed my mind when I was working on the common base class, > originally, wrt. dma_enabled. I vaguely remember that there was some > problem with moving up the property. Ultimately the reviewers didn't > expect me, or suggest, to move it up, hence the current status. > > I think it's out of scope for this series. If you (or someone else) can > do it, I agree it would be an improvement, but I'd rather learn the > method from someone else's patch than experiment with it myself. Agreed. > > > If there's a consensus on the x- prefix and/or the underscore/hyphen > question, I'm happy to send a v6 with those changes. I don't mind about the underscore, but IMO the "x-" prefix is important.
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..313d943ebd27 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("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("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);
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 (and device property) FWCfgState.file_slots. 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> --- Notes: 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(-)