Re: [PATCH v4 kvmtool 08/12] builtin_run: Allow standard size specifiers for memory
From: Andre Przywara <andre.przywara@arm.com>
Date: 2022-06-16 17:12:06
Also in:
kvmarm
On Thu, 16 Jun 2022 14:48:24 +0100 Alexandru Elisei [off-list ref] wrote:
From: Suzuki K Poulose <suzuki.poulose@arm.com> Allow the user to use the standard B (bytes), K (kilobytes), M (megabytes), G (gigabytes), T (terabytes) and P (petabytes) suffixes for memory size. When none are specified, the default is megabytes. Also raise an error if the guest specifies 0 as the memory size, instead of treating it as uninitialized, as kvmtool has done so far. Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Alexandru Elisei <redacted>
Thanks, looks good now! Reviewed-by: Andre Przywara <andre.przywara@arm.com> Cheers, Andre
quoted hunk ↗ jump to hunk
--- builtin-run.c | 59 ++++++++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 54 insertions(+), 5 deletions(-)diff --git a/builtin-run.c b/builtin-run.c index dcd08f739469..8b4e865f0a0e 100644 --- a/builtin-run.c +++ b/builtin-run.c@@ -49,9 +49,11 @@ #include <ctype.h> #include <stdio.h> -#define MB_SHIFT (20) #define KB_SHIFT (10) +#define MB_SHIFT (20) #define GB_SHIFT (30) +#define TB_SHIFT (40) +#define PB_SHIFT (50) __thread struct kvm_cpu *current_kvm_cpu;@@ -87,6 +89,54 @@ void kvm_run_set_wrapper_sandbox(void) kvm_run_wrapper = KVM_RUN_SANDBOX; } +static int parse_mem_unit(char **next) +{ + switch (**next) { + case 'B': case 'b': (*next)++; return 0; + case 'K': case 'k': (*next)++; return KB_SHIFT; + case 'M': case 'm': (*next)++; return MB_SHIFT; + case 'G': case 'g': (*next)++; return GB_SHIFT; + case 'T': case 't': (*next)++; return TB_SHIFT; + case 'P': case 'p': (*next)++; return PB_SHIFT; + } + + return MB_SHIFT; +} + +static u64 parse_mem_option(const char *nptr, char **next) +{ + u64 shift; + u64 val; + + errno = 0; + val = strtoull(nptr, next, 10); + if (errno == ERANGE) + die("Memory too large: %s", nptr); + if (*next == nptr) + die("Invalid memory specifier: %s", nptr); + + shift = parse_mem_unit(next); + if ((val << shift) < val) + die("Memory too large: %s", nptr); + + return val << shift; +} + +static int mem_parser(const struct option *opt, const char *arg, int unset) +{ + struct kvm *kvm = opt->ptr; + char *next; + + kvm->cfg.ram_size = parse_mem_option(arg, &next); + if (kvm->cfg.ram_size == 0) + die("Invalid RAM size: %s", arg); + + if (*next != '\0') + die("Invalid memory specifier: %s", arg); + + return 0; +} + #ifndef OPT_ARCH_RUN #define OPT_ARCH_RUN(...) #endif@@ -97,8 +147,9 @@ void kvm_run_set_wrapper_sandbox(void) OPT_STRING('\0', "name", &(cfg)->guest_name, "guest name", \ "A name for the guest"), \ OPT_INTEGER('c', "cpus", &(cfg)->nrcpus, "Number of CPUs"), \ - OPT_U64('m', "mem", &(cfg)->ram_size, "Virtual machine memory" \ - " size in MB."), \ + OPT_CALLBACK('m', "mem", NULL, "size[BKMGTP]", \ + "Virtual machine memory size, by default measured" \ + " in megabytes (M)", mem_parser, kvm), \ OPT_CALLBACK('d', "disk", kvm, "image or rootfs_dir", "Disk " \ " image or rootfs directory", img_name_parser, \ kvm), \@@ -522,8 +573,6 @@ static void kvm_run_validate_cfg(struct kvm *kvm) pr_warning("Ignoring initrd file when loading a firmware image"); if (kvm->cfg.ram_size) { - /* User specifies RAM size in megabytes. */ - kvm->cfg.ram_size <<= MB_SHIFT; available_ram = host_ram_size(); if (available_ram && kvm->cfg.ram_size > available_ram) { pr_warning("Guest memory size %lluMB exceeds host physical RAM size %lluMB",
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