[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [PATCH v2 4/6] xen: add capability to load initrd outside of initial
From: |
Juergen Gross |
Subject: |
Re: [PATCH v2 4/6] xen: add capability to load initrd outside of initial mapping |
Date: |
Thu, 11 Feb 2016 15:13:40 +0100 |
User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.5.0 |
On 11/02/16 13:33, Daniel Kiper wrote:
> On Thu, Feb 11, 2016 at 08:53:24AM +0100, Juergen Gross wrote:
>> Modern pvops linux kernels support an initrd not covered by the initial
>> mapping. This capability is flagged by an elf-note.
>>
>> In case the elf-note is set by the kernel don't place the initrd into
>> the initial mapping. This will allow to load larger initrds and/or
>> support domains with larger memory, as the initial mapping is limited
>> to 2GB and it is containing the p2m list.
>>
>> Signed-off-by: Juergen Gross <address@hidden>
>> ---
>> grub-core/loader/i386/xen.c | 56
>> ++++++++++++++++++++++++++++++--------
>> grub-core/loader/i386/xen_fileXX.c | 3 ++
>> include/grub/xen_file.h | 1 +
>> 3 files changed, 49 insertions(+), 11 deletions(-)
>>
>> diff --git a/grub-core/loader/i386/xen.c b/grub-core/loader/i386/xen.c
>> index 65cec27..0f41048 100644
>> --- a/grub-core/loader/i386/xen.c
>> +++ b/grub-core/loader/i386/xen.c
>> @@ -307,15 +307,14 @@ grub_xen_pt_alloc (void)
>> }
>>
>> static grub_err_t
>> -grub_xen_boot (void)
>> +grub_xen_alloc_end (void)
>> {
>> grub_err_t err;
>> - grub_uint64_t nr_pages;
>> - struct gnttab_set_version gnttab_setver;
>> - grub_size_t i;
>> + static int called = 0;
>>
>> - if (grub_xen_n_allocated_shared_pages)
>> - return grub_error (GRUB_ERR_BUG, "active grants");
>> + if (called)
>> + return GRUB_ERR_NONE;
>
> Why?
Did you look at the function? grub_xen_alloc_end() (some parts of the
original grub_xen_boot()) is new and may be called multiple times. It
was much easier to just call it and let it do what must be done only
at the first time called.
>
>> + called = 1;
>>
>> err = grub_xen_p2m_alloc ();
>> if (err)
>> @@ -327,6 +326,24 @@ grub_xen_boot (void)
>> if (err)
>> return err;
>>
>> + return GRUB_ERR_NONE;
>> +}
>> +
>> +static grub_err_t
>> +grub_xen_boot (void)
>> +{
>> + grub_err_t err;
>> + grub_uint64_t nr_pages;
>> + struct gnttab_set_version gnttab_setver;
>> + grub_size_t i;
>> +
>> + if (grub_xen_n_allocated_shared_pages)
>> + return grub_error (GRUB_ERR_BUG, "active grants");
>
> Why?
That's how it has been before. git just decided to generate the diff
that way.
>
>> + err = grub_xen_alloc_end ();
>> + if (err)
>> + return err;
>> +
>> err = set_mfns (console_pfn);
>> if (err)
>> return err;
>> @@ -587,6 +604,13 @@ grub_cmd_initrd (grub_command_t cmd __attribute__
>> ((unused)),
>> goto fail;
>> }
>>
>> + if (xen_inf.unmapped_initrd)
>> + {
>> + err = grub_xen_alloc_end ();
>> + if (err)
>> + goto fail;
>> + }
>> +
>> if (grub_initrd_init (argc, argv, &initrd_ctx))
>> goto fail;
>>
>> @@ -603,13 +627,22 @@ grub_cmd_initrd (grub_command_t cmd __attribute__
>> ((unused)),
>> goto fail;
>> }
>>
>> - next_start.mod_start = max_addr + xen_inf.virt_base;
>> - next_start.mod_len = size;
>> -
>> - max_addr = ALIGN_UP (max_addr + size, PAGE_SIZE);
>> + if (xen_inf.unmapped_initrd)
>> + {
>> + next_start.flags |= SIF_MOD_START_PFN;
>> + next_start.mod_start = max_addr >> PAGE_SHIFT;
>> + next_start.mod_len = size;
>> + }
>> + else
>> + {
>> + next_start.mod_start = max_addr + xen_inf.virt_base;
>> + next_start.mod_len = size;
>> + }
>>
>> grub_dprintf ("xen", "Initrd, addr=0x%x, size=0x%x\n",
>> - (unsigned) next_start.mod_start, (unsigned) size);
>> + (unsigned) (max_addr + xen_inf.virt_base), (unsigned) size);
>> +
>> + max_addr = ALIGN_UP (max_addr + size, PAGE_SIZE);
>>
>> fail:
>> grub_initrd_close (&initrd_ctx);
>> @@ -660,6 +693,7 @@ grub_cmd_module (grub_command_t cmd __attribute__
>> ((unused)),
>>
>> if (!xen_module_info_page)
>> {
>> + xen_inf.unmapped_initrd = 0;
>> n_modules = 0;
>> max_addr = ALIGN_UP (max_addr, PAGE_SIZE);
>> modules_target_start = max_addr;
>> diff --git a/grub-core/loader/i386/xen_fileXX.c
>> b/grub-core/loader/i386/xen_fileXX.c
>> index 1ba5649..69fccd2 100644
>> --- a/grub-core/loader/i386/xen_fileXX.c
>> +++ b/grub-core/loader/i386/xen_fileXX.c
>> @@ -253,6 +253,9 @@ parse_note (grub_elf_t elf, struct grub_xen_file_info
>> *xi,
>> descsz == 2 ? 2 : 3) == 0)
>> xi->arch = GRUB_XEN_FILE_I386;
>> break;
>> + case 16:
>
> Could you define this a constant and use it here?
This would be the only case with a constant. All others are numeric
as well.
Juergen
- [PATCH v2 0/6] grub-xen: support booting huge pv-domains, Juergen Gross, 2016/02/11
- [PATCH v2 2/6] xen: factor out allocation of special pages into separate function, Juergen Gross, 2016/02/11
- [PATCH v2 6/6] xen: add capability to load p2m list outside of kernel mapping, Juergen Gross, 2016/02/11
- [PATCH v2 4/6] xen: add capability to load initrd outside of initial mapping, Juergen Gross, 2016/02/11
- Re: [PATCH v2 4/6] xen: add capability to load initrd outside of initial mapping, Vladimir 'φ-coder/phcoder' Serbinenko, 2016/02/12
- Re: [PATCH v2 4/6] xen: add capability to load initrd outside of initial mapping, Juergen Gross, 2016/02/12
[PATCH v2 1/6] xen: factor out p2m list allocation into separate function, Juergen Gross, 2016/02/11