| Message ID | 20210728102758.3269446-11-penny.zheng@arm.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Domain on Static Allocation | expand |
Hi Penny, On 28/07/2021 11:27, Penny Zheng wrote: > This commit introduces allocate_static_memory to allocate static memory as > guest RAM for Domain on Static Allocation. > > It uses acquire_domstatic_pages to acquire pre-configured static memory > for this domain, and uses guest_physmap_add_page to set up P2M table. > These pre-defined static memory banks shall be firstly mapped to the > fixed guest RAM address `GUEST_RAM0_BASE`. And until it exhausts the > `GUEST_RAM0_SIZE`, it will seek to `GUEST_RAM1_BASE`, and so on. > `GUEST_RAM0` may take up several pre-defined physical RAM regions. > > Signed-off-by: Penny Zheng <penny.zheng@arm.com> > --- > xen/arch/arm/domain_build.c | 137 +++++++++++++++++++++++++++++++++++- > 1 file changed, 135 insertions(+), 2 deletions(-) > > diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c > index cdb16f2086..ed290ee31b 100644 > --- a/xen/arch/arm/domain_build.c > +++ b/xen/arch/arm/domain_build.c > @@ -480,6 +480,139 @@ fail: > (unsigned long)kinfo->unassigned_mem >> 10); > } > > +static bool __init append_static_memory_to_bank(struct domain *d, > + struct membank *bank, > + mfn_t smfn, > + paddr_t size) > +{ > + int res; > + paddr_t tot_size = size; > + /* Infer next GFN. */ > + gfn_t sgfn = gaddr_to_gfn(bank->start + bank->size); > + > + while ( tot_size > 0 ) > + { > + unsigned int order = get_allocation_size(tot_size); > + > + res = guest_physmap_add_page(d, sgfn, smfn, order); > + if ( res ) > + { > + dprintk(XENLOG_ERR, "Failed map pages to DOMU: %d", res); > + return false; > + } > + > + smfn = mfn_add(smfn, 1UL << order); > + tot_size -= (1UL << (PAGE_SHIFT + order)); > + } AFAICT, the loop is only here to suit guest_physmap_add_page(). Further down the line, the order will be converted back to a number of pages before calling p2m_insert_mapping(). So how about exporting p2m_insert_mapping() and use it? > + > + bank->size = bank->size + size; We usually add a newline before the last return of the function. > + return true; > +} > + > +/* Allocate memory from static memory as RAM for one specific domain d. */ > +static void __init allocate_static_memory(struct domain *d, > + struct kernel_info *kinfo, > + const struct dt_property *prop, > + u32 addr_cells, u32 size_cells) > +{ > + unsigned int nr_banks, gbank, bank = 0; > + const uint64_t rambase[] = GUEST_RAM_BANK_BASES; > + const uint64_t ramsize[] = GUEST_RAM_BANK_SIZES; > + const __be32 *cell; > + u32 reg_cells = addr_cells + size_cells; > + u64 tot_size = 0; > + paddr_t pbase, psize, gsize; > + mfn_t smfn; > + > + /* Start with GUEST_RAM0. */ > + kinfo->mem.nr_banks = 0; > + gbank = 0; > + gsize = ramsize[gbank]; > + kinfo->mem.bank[gbank].start = rambase[gbank]; > + > + cell = (const __be32 *)prop->value; > + nr_banks = (prop->length) / (reg_cells * sizeof (u32)); > + BUG_ON(nr_banks > NR_MEM_BANKS); > + > + while ( bank < nr_banks ) > + { > + device_tree_get_reg(&cell, addr_cells, size_cells, &pbase, &psize); > + tot_size += psize; > + smfn = maddr_to_mfn(pbase); > + > + if ( !acquire_domstatic_pages(d, psize >> PAGE_SHIFT, smfn, 0) ) I think we want to check that both pbase and psize are page aligned first. This can be done here or earlier when reserving the pages (this would be a previous patch). Also, given that you can easily figure out the page from the mfn. I think it would be better for acquire_domstatic_pages() to return an error. This could be helpful to figure out an error. > + { > + printk(XENLOG_ERR > + "%pd: cannot acquire static memory " > + "(0x%"PRIpaddr" - 0x%"PRIpaddr").\n", > + d, pbase, pbase + psize); > + goto fail; > + } > + > + printk(XENLOG_INFO "%pd: STATIC BANK[%d] %#"PRIpaddr"-%#"PRIpaddr"\n", bank is unsigned so s/%d/%u/ > + d, bank, pbase, pbase + psize); > + > + /* > + * It shall be mapped to the fixed guest RAM address rambase[i], > + * And until it exhausts the ramsize[i], it will seek to the next > + * rambase[i+1]. > + */ > + while ( 1 ) > + { > + /* > + * The current physical bank is fully mapped. > + * Handle the next physical bank. > + */ > + if ( gsize >= psize ) > + { > + if ( !append_static_memory_to_bank(d, &kinfo->mem.bank[gbank], > + smfn, psize) ) > + goto fail; > + > + gsize = gsize - psize; > + bank++; > + break; > + } > + /* > + * Current guest bank memory is not enough to map. > + * Check if we have another guest bank available. > + * gbank refers guest memory bank index. > + */ > + else if ( (gbank + 2) > GUEST_RAM_BANKS ) { I don't understand the +2. Can you clarify it? Also, the coding style for Xen requires the { to be on a separate line. > + printk("Exhausted the number of guest bank\n"); > + goto fail; > + } > + else > + { > + if ( !append_static_memory_to_bank(d, &kinfo->mem.bank[gbank], > + smfn, gsize) ) > + goto fail; As I may have mentionned earlier, I find the double loop quite difficult to read. I don't think we can drop the double loop, but we can at least try to simplify the code in the loops. The one I can think right now is moving allocate_static_memory_to_bank() outside of the if/else. Something like: /* Map as much as possible the static range to the guest bank */ if ( !allocate_static_bank(.., min(psize, gize)) ) > + > + psize = psize - gsize; > + smfn = mfn_add(smfn, gsize >> PAGE_SHIFT); > + /* Update to the next guest bank. */ > + gbank++; > + gsize = ramsize[gbank]; > + kinfo->mem.bank[gbank].start = rambase[gbank]; > + } > + } > + } > + > + kinfo->mem.nr_banks = ++gbank; > + kinfo->unassigned_mem -= tot_size; > + if ( kinfo->unassigned_mem ) > + printk(XENLOG_ERR > + "Size of \"memory\" property doesn't match up with the ones " > + "defined in \"xen,static-mem\".\n"); We don't split the single line message accross multi-line even if the result code is more than 80 characters long. > + > + return; > + > +fail: > + panic("Failed to allocate requested static memory for domain %pd." > + "Fix the VMs configurations.\n", Same here. > + d); > +} > + > static int __init write_properties(struct domain *d, struct kernel_info *kinfo, > const struct dt_device_node *node) > { > @@ -2486,8 +2619,8 @@ static int __init construct_domU(struct domain *d, > if ( !static_mem ) > allocate_memory(d, &kinfo); > else > - /* TODO: allocate_static_memory(...). */ > - BUG(); > + allocate_static_memory(d, &kinfo, static_mem_prop, > + static_mem_addr_cells, static_mem_size_cells); > > rc = prepare_dtb_domU(d, &kinfo); > if ( rc < 0 ) > Cheers,
Hi julien > -----Original Message----- > From: Julien Grall <julien@xen.org> > Sent: Friday, August 13, 2021 9:37 PM > To: Penny Zheng <Penny.Zheng@arm.com>; xen-devel@lists.xenproject.org; > sstabellini@kernel.org > Cc: Bertrand Marquis <Bertrand.Marquis@arm.com>; Wei Chen > <Wei.Chen@arm.com>; nd <nd@arm.com> > Subject: Re: [PATCH V4 10/10] xen/arm: introduce allocate_static_memory > > Hi Penny, > > On 28/07/2021 11:27, Penny Zheng wrote: > > This commit introduces allocate_static_memory to allocate static > > memory as guest RAM for Domain on Static Allocation. > > > > It uses acquire_domstatic_pages to acquire pre-configured static > > memory for this domain, and uses guest_physmap_add_page to set up P2M > table. > > These pre-defined static memory banks shall be firstly mapped to the > > fixed guest RAM address `GUEST_RAM0_BASE`. And until it exhausts the > > `GUEST_RAM0_SIZE`, it will seek to `GUEST_RAM1_BASE`, and so on. > > `GUEST_RAM0` may take up several pre-defined physical RAM regions. > > > > Signed-off-by: Penny Zheng <penny.zheng@arm.com> > > --- > > xen/arch/arm/domain_build.c | 137 > +++++++++++++++++++++++++++++++++++- > > 1 file changed, 135 insertions(+), 2 deletions(-) > > > > diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c > > index cdb16f2086..ed290ee31b 100644 > > --- a/xen/arch/arm/domain_build.c > > +++ b/xen/arch/arm/domain_build.c > > @@ -480,6 +480,139 @@ fail: > > (unsigned long)kinfo->unassigned_mem >> 10); > > } > > > > +static bool __init append_static_memory_to_bank(struct domain *d, > > + struct membank *bank, > > + mfn_t smfn, > > + paddr_t size) { > > + int res; > > + paddr_t tot_size = size; > > + /* Infer next GFN. */ > > + gfn_t sgfn = gaddr_to_gfn(bank->start + bank->size); > > + > > + while ( tot_size > 0 ) > > + { > > + unsigned int order = get_allocation_size(tot_size); > > + > > + res = guest_physmap_add_page(d, sgfn, smfn, order); > > + if ( res ) > > + { > > + dprintk(XENLOG_ERR, "Failed map pages to DOMU: %d", res); > > + return false; > > + } > > + > > + smfn = mfn_add(smfn, 1UL << order); > > + tot_size -= (1UL << (PAGE_SHIFT + order)); > > + } > > AFAICT, the loop is only here to suit guest_physmap_add_page(). Further > down the line, the order will be converted back to a number of pages before > calling p2m_insert_mapping(). > > So how about exporting p2m_insert_mapping() and use it? > Sure. Looks perfect to me. > > + > + bank->size = bank->size + size; > > We usually add a newline before the last return of the function. > > > + return true; > > +} > > + > > +/* Allocate memory from static memory as RAM for one specific domain > > +d. */ static void __init allocate_static_memory(struct domain *d, > > + struct kernel_info *kinfo, > > + const struct dt_property *prop, > > + u32 addr_cells, u32 > > +size_cells) { > > + unsigned int nr_banks, gbank, bank = 0; > > + const uint64_t rambase[] = GUEST_RAM_BANK_BASES; > > + const uint64_t ramsize[] = GUEST_RAM_BANK_SIZES; > > + const __be32 *cell; > > + u32 reg_cells = addr_cells + size_cells; > > + u64 tot_size = 0; > > + paddr_t pbase, psize, gsize; > > + mfn_t smfn; > > + > > + /* Start with GUEST_RAM0. */ > > + kinfo->mem.nr_banks = 0; > > + gbank = 0; > > + gsize = ramsize[gbank]; > > + kinfo->mem.bank[gbank].start = rambase[gbank]; > > + > > + cell = (const __be32 *)prop->value; > > + nr_banks = (prop->length) / (reg_cells * sizeof (u32)); > > + BUG_ON(nr_banks > NR_MEM_BANKS); > > + > > + while ( bank < nr_banks ) > > + { > > + device_tree_get_reg(&cell, addr_cells, size_cells, &pbase, &psize); > > + tot_size += psize; > > + smfn = maddr_to_mfn(pbase); > > + > > + if ( !acquire_domstatic_pages(d, psize >> PAGE_SHIFT, smfn, > > + 0) ) > > I think we want to check that both pbase and psize are page aligned first. This > can be done here or earlier when reserving the pages (this would be a previous > patch). > I will do the check in static memory initialization, in function init_staticmem_pages. > Also, given that you can easily figure out the page from the mfn. I think it > would be better for acquire_domstatic_pages() to return an error. This could > be helpful to figure out an error. > Sure. I'll return the errno. > > + { > > + printk(XENLOG_ERR > > + "%pd: cannot acquire static memory " > > + "(0x%"PRIpaddr" - 0x%"PRIpaddr").\n", > > + d, pbase, pbase + psize); > > + goto fail; > > + } > > + > > + printk(XENLOG_INFO "%pd: STATIC BANK[%d] > > + %#"PRIpaddr"-%#"PRIpaddr"\n", > > bank is unsigned so s/%d/%u/ > Oh, thx. > > + d, bank, pbase, pbase + psize); > > + > > + /* > > + * It shall be mapped to the fixed guest RAM address rambase[i], > > + * And until it exhausts the ramsize[i], it will seek to the next > > + * rambase[i+1]. > > + */ > > + while ( 1 ) > > + { > > + /* > > + * The current physical bank is fully mapped. > > + * Handle the next physical bank. > > + */ > > + if ( gsize >= psize ) > > + { > > + if ( !append_static_memory_to_bank(d, &kinfo->mem.bank[gbank], > > + smfn, psize) ) > > + goto fail; > > + > > + gsize = gsize - psize; > > + bank++; > > + break; > > + } > > + /* > > + * Current guest bank memory is not enough to map. > > + * Check if we have another guest bank available. > > + * gbank refers guest memory bank index. > > + */ > > + else if ( (gbank + 2) > GUEST_RAM_BANKS ) { > > I don't understand the +2. Can you clarify it? > gbank refers to the index of the guest bank, and here since current guest bank(gbank) memory is not enough to map, users seeks to the next one(gbank + 1), gbank + 2 is the number of requested guest memory banks right now, and shall not be larger than GUEST_RAM_BANKS. > Also, the coding style for Xen requires the { to be on a separate line. > Sure. > > + printk("Exhausted the number of guest bank\n"); > > + goto fail; > > + } > > + else > > + { > > + if ( !append_static_memory_to_bank(d, &kinfo->mem.bank[gbank], > > + smfn, gsize) ) > > + goto fail; > > As I may have mentionned earlier, I find the double loop quite difficult to read. > I don't think we can drop the double loop, but we can at least try to simplify > the code in the loops. > > The one I can think right now is moving allocate_static_memory_to_bank() > outside of the if/else. Something like: > > /* Map as much as possible the static range to the guest bank */ if > ( !allocate_static_bank(.., min(psize, gize)) ) > Sure, will do. > > + > > + psize = psize - gsize; > > + smfn = mfn_add(smfn, gsize >> PAGE_SHIFT); > > + /* Update to the next guest bank. */ > > + gbank++; > > + gsize = ramsize[gbank]; > > + kinfo->mem.bank[gbank].start = rambase[gbank]; > > + } > > + } > > + } > > + > > + kinfo->mem.nr_banks = ++gbank; > > + kinfo->unassigned_mem -= tot_size; > > + if ( kinfo->unassigned_mem ) > > + printk(XENLOG_ERR > > + "Size of \"memory\" property doesn't match up with the ones " > > + "defined in \"xen,static-mem\".\n"); > > We don't split the single line message accross multi-line even if the result code > is more than 80 characters long. > Sure. > > + > > + return; > > + > > +fail: > > + panic("Failed to allocate requested static memory for domain %pd." > > + "Fix the VMs configurations.\n", > > Same here. > > > + d); > > +} > > + > > static int __init write_properties(struct domain *d, struct kernel_info *kinfo, > > const struct dt_device_node *node) > > { > > @@ -2486,8 +2619,8 @@ static int __init construct_domU(struct domain *d, > > if ( !static_mem ) > > allocate_memory(d, &kinfo); > > else > > - /* TODO: allocate_static_memory(...). */ > > - BUG(); > > + allocate_static_memory(d, &kinfo, static_mem_prop, > > + static_mem_addr_cells, > > + static_mem_size_cells); > > > > rc = prepare_dtb_domU(d, &kinfo); > > if ( rc < 0 ) > > > > Cheers, > > -- Cheers Penny > Julien Grall
On 16/08/2021 08:51, Penny Zheng wrote: >>> + d, bank, pbase, pbase + psize); >>> + >>> + /* >>> + * It shall be mapped to the fixed guest RAM address rambase[i], >>> + * And until it exhausts the ramsize[i], it will seek to the next >>> + * rambase[i+1]. >>> + */ >>> + while ( 1 ) >>> + { >>> + /* >>> + * The current physical bank is fully mapped. >>> + * Handle the next physical bank. >>> + */ >>> + if ( gsize >= psize ) >>> + { >>> + if ( !append_static_memory_to_bank(d, &kinfo->mem.bank[gbank], >>> + smfn, psize) ) >>> + goto fail; >>> + >>> + gsize = gsize - psize; >>> + bank++; >>> + break; >>> + } >>> + /* >>> + * Current guest bank memory is not enough to map. >>> + * Check if we have another guest bank available. >>> + * gbank refers guest memory bank index. >>> + */ >>> + else if ( (gbank + 2) > GUEST_RAM_BANKS ) { >> >> I don't understand the +2. Can you clarify it? >> > > gbank refers to the index of the guest bank, and here since current guest bank(gbank) > memory is not enough to map, users seeks to the next one(gbank + 1), > > gbank + 2 is the number of requested guest memory banks right now, and shall not be > larger than GUEST_RAM_BANKS. Thanks for the clarification. When I read "2" I tend to think we are checking the bank after the next. How about writing: (gbank + 1) >= GUEST_RAM_BANKS or gbank >= (GUEST_RAM_BANKS - 1) This as the same end results, but we check the index rather than the number of banks. Anyway, I can settle with 2 if you really prefer it. Cheers,
> -----Original Message----- > From: Julien Grall <julien@xen.org> > Sent: Tuesday, August 17, 2021 1:55 AM > To: Penny Zheng <Penny.Zheng@arm.com>; xen-devel@lists.xenproject.org; > sstabellini@kernel.org > Cc: Bertrand Marquis <Bertrand.Marquis@arm.com>; Wei Chen > <Wei.Chen@arm.com>; nd <nd@arm.com> > Subject: Re: [PATCH V4 10/10] xen/arm: introduce allocate_static_memory > > > > On 16/08/2021 08:51, Penny Zheng wrote: > >>> + d, bank, pbase, pbase + psize); > >>> + > >>> + /* > >>> + * It shall be mapped to the fixed guest RAM address rambase[i], > >>> + * And until it exhausts the ramsize[i], it will seek to the next > >>> + * rambase[i+1]. > >>> + */ > >>> + while ( 1 ) > >>> + { > >>> + /* > >>> + * The current physical bank is fully mapped. > >>> + * Handle the next physical bank. > >>> + */ > >>> + if ( gsize >= psize ) > >>> + { > >>> + if ( !append_static_memory_to_bank(d, &kinfo- > >mem.bank[gbank], > >>> + smfn, psize) ) > >>> + goto fail; > >>> + > >>> + gsize = gsize - psize; > >>> + bank++; > >>> + break; > >>> + } > >>> + /* > >>> + * Current guest bank memory is not enough to map. > >>> + * Check if we have another guest bank available. > >>> + * gbank refers guest memory bank index. > >>> + */ > >>> + else if ( (gbank + 2) > GUEST_RAM_BANKS ) { > >> > >> I don't understand the +2. Can you clarify it? > >> > > > > gbank refers to the index of the guest bank, and here since current guest > bank(gbank) > > memory is not enough to map, users seeks to the next one(gbank + 1), > > > > gbank + 2 is the number of requested guest memory banks right now, and > > shall not be larger than GUEST_RAM_BANKS. > > Thanks for the clarification. When I read "2" I tend to think we are checking > the bank after the next. How about writing: > > (gbank + 1) >= GUEST_RAM_BANKS > > or > > gbank >= (GUEST_RAM_BANKS - 1) > > This as the same end results, but we check the index rather than the number of > banks. > > Anyway, I can settle with 2 if you really prefer it. > Nah, I'll take your suggestion. Yours is more generic. > Cheers, > > -- > Julien Grall
diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c index cdb16f2086..ed290ee31b 100644 --- a/xen/arch/arm/domain_build.c +++ b/xen/arch/arm/domain_build.c @@ -480,6 +480,139 @@ fail: (unsigned long)kinfo->unassigned_mem >> 10); } +static bool __init append_static_memory_to_bank(struct domain *d, + struct membank *bank, + mfn_t smfn, + paddr_t size) +{ + int res; + paddr_t tot_size = size; + /* Infer next GFN. */ + gfn_t sgfn = gaddr_to_gfn(bank->start + bank->size); + + while ( tot_size > 0 ) + { + unsigned int order = get_allocation_size(tot_size); + + res = guest_physmap_add_page(d, sgfn, smfn, order); + if ( res ) + { + dprintk(XENLOG_ERR, "Failed map pages to DOMU: %d", res); + return false; + } + + smfn = mfn_add(smfn, 1UL << order); + tot_size -= (1UL << (PAGE_SHIFT + order)); + } + + bank->size = bank->size + size; + return true; +} + +/* Allocate memory from static memory as RAM for one specific domain d. */ +static void __init allocate_static_memory(struct domain *d, + struct kernel_info *kinfo, + const struct dt_property *prop, + u32 addr_cells, u32 size_cells) +{ + unsigned int nr_banks, gbank, bank = 0; + const uint64_t rambase[] = GUEST_RAM_BANK_BASES; + const uint64_t ramsize[] = GUEST_RAM_BANK_SIZES; + const __be32 *cell; + u32 reg_cells = addr_cells + size_cells; + u64 tot_size = 0; + paddr_t pbase, psize, gsize; + mfn_t smfn; + + /* Start with GUEST_RAM0. */ + kinfo->mem.nr_banks = 0; + gbank = 0; + gsize = ramsize[gbank]; + kinfo->mem.bank[gbank].start = rambase[gbank]; + + cell = (const __be32 *)prop->value; + nr_banks = (prop->length) / (reg_cells * sizeof (u32)); + BUG_ON(nr_banks > NR_MEM_BANKS); + + while ( bank < nr_banks ) + { + device_tree_get_reg(&cell, addr_cells, size_cells, &pbase, &psize); + tot_size += psize; + smfn = maddr_to_mfn(pbase); + + if ( !acquire_domstatic_pages(d, psize >> PAGE_SHIFT, smfn, 0) ) + { + printk(XENLOG_ERR + "%pd: cannot acquire static memory " + "(0x%"PRIpaddr" - 0x%"PRIpaddr").\n", + d, pbase, pbase + psize); + goto fail; + } + + printk(XENLOG_INFO "%pd: STATIC BANK[%d] %#"PRIpaddr"-%#"PRIpaddr"\n", + d, bank, pbase, pbase + psize); + + /* + * It shall be mapped to the fixed guest RAM address rambase[i], + * And until it exhausts the ramsize[i], it will seek to the next + * rambase[i+1]. + */ + while ( 1 ) + { + /* + * The current physical bank is fully mapped. + * Handle the next physical bank. + */ + if ( gsize >= psize ) + { + if ( !append_static_memory_to_bank(d, &kinfo->mem.bank[gbank], + smfn, psize) ) + goto fail; + + gsize = gsize - psize; + bank++; + break; + } + /* + * Current guest bank memory is not enough to map. + * Check if we have another guest bank available. + * gbank refers guest memory bank index. + */ + else if ( (gbank + 2) > GUEST_RAM_BANKS ) { + printk("Exhausted the number of guest bank\n"); + goto fail; + } + else + { + if ( !append_static_memory_to_bank(d, &kinfo->mem.bank[gbank], + smfn, gsize) ) + goto fail; + + psize = psize - gsize; + smfn = mfn_add(smfn, gsize >> PAGE_SHIFT); + /* Update to the next guest bank. */ + gbank++; + gsize = ramsize[gbank]; + kinfo->mem.bank[gbank].start = rambase[gbank]; + } + } + } + + kinfo->mem.nr_banks = ++gbank; + kinfo->unassigned_mem -= tot_size; + if ( kinfo->unassigned_mem ) + printk(XENLOG_ERR + "Size of \"memory\" property doesn't match up with the ones " + "defined in \"xen,static-mem\".\n"); + + return; + +fail: + panic("Failed to allocate requested static memory for domain %pd." + "Fix the VMs configurations.\n", + d); +} + static int __init write_properties(struct domain *d, struct kernel_info *kinfo, const struct dt_device_node *node) { @@ -2486,8 +2619,8 @@ static int __init construct_domU(struct domain *d, if ( !static_mem ) allocate_memory(d, &kinfo); else - /* TODO: allocate_static_memory(...). */ - BUG(); + allocate_static_memory(d, &kinfo, static_mem_prop, + static_mem_addr_cells, static_mem_size_cells); rc = prepare_dtb_domU(d, &kinfo); if ( rc < 0 )
This commit introduces allocate_static_memory to allocate static memory as guest RAM for Domain on Static Allocation. It uses acquire_domstatic_pages to acquire pre-configured static memory for this domain, and uses guest_physmap_add_page to set up P2M table. These pre-defined static memory banks shall be firstly mapped to the fixed guest RAM address `GUEST_RAM0_BASE`. And until it exhausts the `GUEST_RAM0_SIZE`, it will seek to `GUEST_RAM1_BASE`, and so on. `GUEST_RAM0` may take up several pre-defined physical RAM regions. Signed-off-by: Penny Zheng <penny.zheng@arm.com> --- xen/arch/arm/domain_build.c | 137 +++++++++++++++++++++++++++++++++++- 1 file changed, 135 insertions(+), 2 deletions(-)