[Libguestfs] [PATCH] v2v: linux: Move kernel detection to a separate module.

Create a new module [Linux_kernels] which does all kernel detection, and also provides a place to define the kernel_info data structure. This is essentially just code motion. --- v2v/Makefile.am | 2 + v2v/convert_linux.ml | 219 +++-------------------------------------------- v2v/linux_kernels.ml | 230 ++++++++++++++++++++++++++++++++++++++++++++++++++ v2v/linux_kernels.mli | 50 +++++++++++ 4 files changed, 295 insertions(+), 206 deletions(-) create mode 100644 v2v/linux_kernels.ml create mode 100644 v2v/linux_kernels.mli diff --git a/v2v/Makefile.am b/v2v/Makefile.am index 34f7976..a2f6969 100644 --- a/v2v/Makefile.am +++ b/v2v/Makefile.am @@ -41,6 +41,7 @@ SOURCES_MLI = \ inspect_source.mli \ linux.mli \ linux_bootloaders.mli \ + linux_kernels.mli \ modules_list.mli \ name_from_disk.mli \ output_glance.mli \ @@ -85,6 +86,7 @@ SOURCES_ML = \ input_libvirt.ml \ input_ova.ml \ linux_bootloaders.ml \ + linux_kernels.ml \ convert_linux.ml \ convert_windows.ml \ output_null.ml \ diff --git a/v2v/convert_linux.ml b/v2v/convert_linux.ml index b85406e..500e060 100644 --- a/v2v/convert_linux.ml +++ b/v2v/convert_linux.ml @@ -33,31 +33,10 @@ open Common_utils open Utils open Types +open Linux_kernels module G = Guestfs -(* Kernel information. *) -type kernel_info = { - ki_app : G.application2; (* The RPM package data. *) - ki_name : string; (* eg. "kernel-PAE" *) - ki_version : string; (* version-release *) - ki_arch : string; (* Kernel architecture. *) - ki_vmlinuz : string; (* The path of the vmlinuz file. *) - ki_vmlinuz_stat : G.statns; (* stat(2) of vmlinuz *) - ki_initrd : string option; (* Path of initramfs, if found. *) - ki_modpath : string; (* The module path. *) - ki_modules : string list; (* The list of module names. *) - ki_supports_virtio : bool; (* Kernel has virtio drivers? *) - ki_is_xen_kernel : bool; (* Is a Xen paravirt kernel? *) - ki_is_debug : bool; (* Is debug kernel? *) -} - -let string_of_kernel_info ki = - sprintf "(%s, %s, %s, %s, %s, virtio=%b, xen=%b, debug=%b)" - ki.ki_name ki.ki_version ki.ki_arch ki.ki_vmlinuz - (match ki.ki_initrd with None -> "None" | Some f -> f) - ki.ki_supports_virtio ki.ki_is_xen_kernel ki.ki_is_debug - (* The conversion function. *) let rec convert ~keep_serial_console (g : G.guestfs) inspect source rcaps = (*----------------------------------------------------------------------*) @@ -92,193 +71,21 @@ let rec convert ~keep_serial_console (g : G.guestfs) inspect source rcaps = let bootloader = Linux_bootloaders.detect_bootloader g inspect in Linux.augeas_reload g; - (* What kernel/kernel-like packages are installed on the current guest? *) - let installed_kernels : kernel_info list = - let rex_ko = Str.regexp ".*\\.k?o\\(\\.xz\\)?$" in - let rex_ko_extract = Str.regexp ".*/\\([^/]+\\)\\.k?o\\(\\.xz\\)?$" in - let rex_initrd = - if family = `Debian_family then - Str.regexp "^initrd.img-.*$" - else - Str.regexp "^initr\\(d\\|amfs\\)-.*\\(\\.img\\)?$" in - filter_map ( - function - | { G.app2_name = name } as app - when name = "kernel" || String.is_prefix name "kernel-" - || String.is_prefix name "linux-image-" -> - (try - (* For each kernel, list the files directly owned by the kernel. *) - let files = Linux.file_list_of_package g inspect app in - - if files = [] then ( - warning (f_"package '%s' contains no files") name; - None - ) - else ( - (* Which of these is the kernel itself? *) - let vmlinuz = List.find ( - fun filename -> String.is_prefix filename "/boot/vmlinuz-" - ) files in - (* Which of these is the modpath? *) - let modpath = List.find ( - fun filename -> - String.length filename >= 14 && - String.is_prefix filename "/lib/modules/" - ) files in - - (* Check vmlinuz & modpath exist. *) - if not (g#is_dir ~followsymlinks:true modpath) then - raise Not_found; - let vmlinuz_stat = - try g#statns vmlinuz with G.Error _ -> raise Not_found in - - (* Get/construct the version. XXX Read this from kernel file. *) - let version = - let prefix_len = String.length "/lib/modules/" in - String.sub modpath prefix_len (String.length modpath - prefix_len) in - - (* Find the initramfs which corresponds to the kernel. - * Since the initramfs is built at runtime, and doesn't have - * to be covered by the RPM file list, this is basically - * guesswork. - *) - let initrd = - let files = g#ls "/boot" in - let files = Array.to_list files in - let files = - List.filter (fun n -> Str.string_match rex_initrd n 0) files in - let files = - List.filter ( - fun n -> - String.find n version >= 0 - ) files in - (* Don't consider kdump initramfs images (RHBZ#1138184). *) - let files = - List.filter (fun n -> String.find n "kdump" == -1) files in - (* If several files match, take the shortest match. This - * handles the case where we have a mix of same-version non-Xen - * and Xen kernels: - * initrd-2.6.18-308.el5.img - * initrd-2.6.18-308.el5xen.img - * and kernel 2.6.18-308.el5 (non-Xen) will match both - * (RHBZ#1141145). - *) - let cmp a b = compare (String.length a) (String.length b) in - let files = List.sort cmp files in - match files with - | [] -> - warning (f_"no initrd was found in /boot matching %s %s.") - name version; - None - | x :: _ -> Some ("/boot/" ^ x) in - - (* Get all modules, which might include custom-installed - * modules that don't appear in 'files' list above. - *) - let modules = g#find modpath in - let modules = Array.to_list modules in - let modules = - List.filter (fun m -> Str.string_match rex_ko m 0) modules in - assert (List.length modules > 0); - - (* Determine the kernel architecture by looking at the - * architecture of an arbitrary kernel module. - *) - let arch = - let any_module = modpath ^ List.hd modules in - g#file_architecture any_module in - - (* Just return the module names, without path or extension. *) - let modules = filter_map ( - fun m -> - if Str.string_match rex_ko_extract m 0 then - Some (Str.matched_group 1 m) - else - None - ) modules in - assert (List.length modules > 0); - - let supports_virtio = List.mem "virtio_net" modules in - let is_xen_kernel = List.mem "xennet" modules in - - (* If the package name is like "kernel-debug", then it's - * a debug kernel. - *) - let is_debug = - String.is_suffix app.G.app2_name "-debug" || - String.is_suffix app.G.app2_name "-dbg" in - - Some { - ki_app = app; - ki_name = name; - ki_version = version; - ki_arch = arch; - ki_vmlinuz = vmlinuz; - ki_vmlinuz_stat = vmlinuz_stat; - ki_initrd = initrd; - ki_modpath = modpath; - ki_modules = modules; - ki_supports_virtio = supports_virtio; - ki_is_xen_kernel = is_xen_kernel; - ki_is_debug = is_debug; - } - ) - - with Not_found -> None - ) - - | _ -> None - ) inspect.i_apps in - - if verbose () then ( - eprintf "installed kernel packages in this guest:\n"; - List.iter ( - fun kernel -> eprintf "\t%s\n" (string_of_kernel_info kernel) - ) installed_kernels; - flush stderr - ); - - if installed_kernels = [] then - error (f_"no installed kernel packages were found.\n\nThis probably indicates that %s was unable to inspect this guest properly.") - prog; - - (* Now the difficult bit. Get the grub kernels. The first in this - * list is the default booting kernel. - *) - let grub_kernels : kernel_info list = - let vmlinuzes = bootloader#list_kernels in - - (* Map these to installed kernels. *) - filter_map ( - fun vmlinuz -> - try - let statbuf = g#statns vmlinuz in - let kernel = - List.find ( - fun { ki_vmlinuz_stat = s } -> - statbuf.G.st_dev = s.G.st_dev && statbuf.G.st_ino = s.G.st_ino - ) installed_kernels in - Some kernel - with - | Not_found -> None - | G.Error msg as exn -> - (* If it isn't "no such file or directory", then re-raise it. *) - if g#last_errno () <> G.Errno.errno_ENOENT then raise exn; - warning (f_"ignoring kernel %s in grub, as it does not exist.") - vmlinuz; - None - ) vmlinuzes in + (* Detect which kernels are installed and offered by the bootloader. *) + let bootloader_kernels = + Linux_kernels.detect_kernels g inspect family bootloader in if verbose () then ( - eprintf "grub kernels in this guest (first in list is default):\n"; + eprintf "kernels offered by the bootloader in this guest (first in list is default):\n"; List.iter ( - fun kernel -> eprintf "\t%s\n" (string_of_kernel_info kernel) - ) grub_kernels; + fun kernel -> + eprintf "\t%s\n" (Linux_kernels.string_of_kernel_info kernel) + ) bootloader_kernels; flush stderr ); - if grub_kernels = [] then - error (f_"no kernels were found in the grub configuration.\n\nThis probably indicates that %s was unable to parse the grub configuration of this guest.") + if bootloader_kernels = [] then + error (f_"no kernels were found in the bootloader configuration.\n\nThis probably indicates that %s was unable to parse the grub configuration of this guest.") prog; (*----------------------------------------------------------------------*) @@ -592,7 +399,7 @@ let rec convert ~keep_serial_console (g : G.guestfs) inspect source rcaps = (* Check a non-Xen kernel exists. *) let only_xen_kernels = List.for_all ( fun { ki_is_xen_kernel = is_xen_kernel } -> is_xen_kernel - ) grub_kernels in + ) bootloader_kernels in if only_xen_kernels then error (f_"only Xen kernels are installed in this guest.\n\nRead the %s(1) manual, section \"XEN PARAVIRTUALIZED GUESTS\", to see what to do.") prog; @@ -610,12 +417,12 @@ let rec convert ~keep_serial_console (g : G.guestfs) inspect source rcaps = else compare k2.ki_is_debug k1.ki_is_debug ) in - let kernels = grub_kernels in + let kernels = bootloader_kernels in let kernels = List.filter (fun { ki_is_xen_kernel = is_xen_kernel } -> not is_xen_kernel) kernels in let kernels = List.sort compare_best_kernels kernels in let kernels = List.rev kernels (* so best is first *) in List.hd kernels in - if best_kernel <> List.hd grub_kernels then + if best_kernel <> List.hd bootloader_kernels then bootloader#set_default_kernel best_kernel.ki_vmlinuz; (* Does the best/bootable kernel support virtio? *) diff --git a/v2v/linux_kernels.ml b/v2v/linux_kernels.ml new file mode 100644 index 0000000..213e495 --- /dev/null +++ b/v2v/linux_kernels.ml @@ -0,0 +1,230 @@ +(* virt-v2v + * Copyright (C) 2009-2016 Red Hat Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + *) + +(* Detect which kernels are installed and offered by the bootloader. *) + +open Printf + +open Common_gettext.Gettext +open Common_utils + +open Types + +module G = Guestfs + +(* Kernel information. *) +type kernel_info = { + ki_app : G.application2; + ki_name : string; + ki_version : string; + ki_arch : string; + ki_vmlinuz : string; + ki_vmlinuz_stat : G.statns; + ki_initrd : string option; + ki_modpath : string; + ki_modules : string list; + ki_supports_virtio : bool; + ki_is_xen_kernel : bool; + ki_is_debug : bool; +} + +let string_of_kernel_info ki = + sprintf "(%s, %s, %s, %s, %s, virtio=%b, xen=%b, debug=%b)" + ki.ki_name ki.ki_version ki.ki_arch ki.ki_vmlinuz + (match ki.ki_initrd with None -> "None" | Some f -> f) + ki.ki_supports_virtio ki.ki_is_xen_kernel ki.ki_is_debug + +let detect_kernels g inspect family bootloader = + (* What kernel/kernel-like packages are installed on the current guest? *) + let installed_kernels : kernel_info list = + let rex_ko = Str.regexp ".*\\.k?o\\(\\.xz\\)?$" in + let rex_ko_extract = Str.regexp ".*/\\([^/]+\\)\\.k?o\\(\\.xz\\)?$" in + let rex_initrd = + if family = `Debian_family then + Str.regexp "^initrd.img-.*$" + else + Str.regexp "^initr\\(d\\|amfs\\)-.*\\(\\.img\\)?$" in + filter_map ( + function + | { G.app2_name = name } as app + when name = "kernel" || String.is_prefix name "kernel-" + || String.is_prefix name "linux-image-" -> + (try + (* For each kernel, list the files directly owned by the kernel. *) + let files = Linux.file_list_of_package g inspect app in + + if files = [] then ( + warning (f_"package '%s' contains no files") name; + None + ) + else ( + (* Which of these is the kernel itself? *) + let vmlinuz = List.find ( + fun filename -> String.is_prefix filename "/boot/vmlinuz-" + ) files in + (* Which of these is the modpath? *) + let modpath = List.find ( + fun filename -> + String.length filename >= 14 && + String.is_prefix filename "/lib/modules/" + ) files in + + (* Check vmlinuz & modpath exist. *) + if not (g#is_dir ~followsymlinks:true modpath) then + raise Not_found; + let vmlinuz_stat = + try g#statns vmlinuz with G.Error _ -> raise Not_found in + + (* Get/construct the version. XXX Read this from kernel file. *) + let version = + let prefix_len = String.length "/lib/modules/" in + String.sub modpath prefix_len (String.length modpath - prefix_len) in + + (* Find the initramfs which corresponds to the kernel. + * Since the initramfs is built at runtime, and doesn't have + * to be covered by the RPM file list, this is basically + * guesswork. + *) + let initrd = + let files = g#ls "/boot" in + let files = Array.to_list files in + let files = + List.filter (fun n -> Str.string_match rex_initrd n 0) files in + let files = + List.filter ( + fun n -> + String.find n version >= 0 + ) files in + (* Don't consider kdump initramfs images (RHBZ#1138184). *) + let files = + List.filter (fun n -> String.find n "kdump" == -1) files in + (* If several files match, take the shortest match. This + * handles the case where we have a mix of same-version non-Xen + * and Xen kernels: + * initrd-2.6.18-308.el5.img + * initrd-2.6.18-308.el5xen.img + * and kernel 2.6.18-308.el5 (non-Xen) will match both + * (RHBZ#1141145). + *) + let cmp a b = compare (String.length a) (String.length b) in + let files = List.sort cmp files in + match files with + | [] -> + warning (f_"no initrd was found in /boot matching %s %s.") + name version; + None + | x :: _ -> Some ("/boot/" ^ x) in + + (* Get all modules, which might include custom-installed + * modules that don't appear in 'files' list above. + *) + let modules = g#find modpath in + let modules = Array.to_list modules in + let modules = + List.filter (fun m -> Str.string_match rex_ko m 0) modules in + assert (List.length modules > 0); + + (* Determine the kernel architecture by looking at the + * architecture of an arbitrary kernel module. + *) + let arch = + let any_module = modpath ^ List.hd modules in + g#file_architecture any_module in + + (* Just return the module names, without path or extension. *) + let modules = filter_map ( + fun m -> + if Str.string_match rex_ko_extract m 0 then + Some (Str.matched_group 1 m) + else + None + ) modules in + assert (List.length modules > 0); + + let supports_virtio = List.mem "virtio_net" modules in + let is_xen_kernel = List.mem "xennet" modules in + + (* If the package name is like "kernel-debug", then it's + * a debug kernel. + *) + let is_debug = + String.is_suffix app.G.app2_name "-debug" || + String.is_suffix app.G.app2_name "-dbg" in + + Some { + ki_app = app; + ki_name = name; + ki_version = version; + ki_arch = arch; + ki_vmlinuz = vmlinuz; + ki_vmlinuz_stat = vmlinuz_stat; + ki_initrd = initrd; + ki_modpath = modpath; + ki_modules = modules; + ki_supports_virtio = supports_virtio; + ki_is_xen_kernel = is_xen_kernel; + ki_is_debug = is_debug; + } + ) + + with Not_found -> None + ) + + | _ -> None + ) inspect.i_apps in + + if verbose () then ( + eprintf "installed kernel packages in this guest:\n"; + List.iter ( + fun kernel -> eprintf "\t%s\n" (string_of_kernel_info kernel) + ) installed_kernels; + flush stderr + ); + + if installed_kernels = [] then + error (f_"no installed kernel packages were found.\n\nThis probably indicates that %s was unable to inspect this guest properly.") + prog; + + (* Now the difficult bit. Get the grub kernels. The first in this + * list is the default booting kernel. + *) + let grub_kernels : kernel_info list = + let vmlinuzes = bootloader#list_kernels in + + (* Map these to installed kernels. *) + filter_map ( + fun vmlinuz -> + try + let statbuf = g#statns vmlinuz in + let kernel = + List.find ( + fun { ki_vmlinuz_stat = s } -> + statbuf.G.st_dev = s.G.st_dev && statbuf.G.st_ino = s.G.st_ino + ) installed_kernels in + Some kernel + with + | Not_found -> None + | G.Error msg as exn -> + (* If it isn't "no such file or directory", then re-raise it. *) + if g#last_errno () <> G.Errno.errno_ENOENT then raise exn; + warning (f_"ignoring kernel %s in grub, as it does not exist.") + vmlinuz; + None + ) vmlinuzes in + + grub_kernels diff --git a/v2v/linux_kernels.mli b/v2v/linux_kernels.mli new file mode 100644 index 0000000..ea2a3b6 --- /dev/null +++ b/v2v/linux_kernels.mli @@ -0,0 +1,50 @@ +(* virt-v2v + * Copyright (C) 2009-2016 Red Hat Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + *) + +(** Detect which kernels are installed and offered by the bootloader. *) + +type kernel_info = { + ki_app : Guestfs.application2; (** The RPM package data. *) + ki_name : string; (** eg. "kernel-PAE" *) + ki_version : string; (** version-release *) + ki_arch : string; (** Kernel architecture. *) + ki_vmlinuz : string; (** The path of the vmlinuz file. *) + ki_vmlinuz_stat : Guestfs.statns;(** stat(2) of vmlinuz *) + ki_initrd : string option; (** Path of initramfs, if found. *) + ki_modpath : string; (** The module path. *) + ki_modules : string list; (** The list of module names. *) + ki_supports_virtio : bool; (** Kernel has virtio drivers? *) + ki_is_xen_kernel : bool; (** Is a Xen paravirt kernel? *) + ki_is_debug : bool; (** Is debug kernel? *) +} +(** Kernel information. *) + +val string_of_kernel_info : kernel_info -> string +(** Display {!kernel_info} struct, eg. for debugging. *) + +val detect_kernels : Guestfs.guestfs -> Types.inspect -> + [> `Debian_family ] -> + < list_kernels : string list; .. > -> + kernel_info list +(** This function detects the kernels offered by the Linux + bootloader (eg. grub). + + It will only return the intersection of kernels that are + installed and kernels that grub knows about. The first + kernel in the returned list is the default boot option, ie. + what the guest would boot without interaction or overrides. *) -- 2.9.3