From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59805) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Xwxk4-0003CW-To for qemu-devel@nongnu.org; Fri, 05 Dec 2014 13:36:43 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Xwxjy-0002zm-KD for qemu-devel@nongnu.org; Fri, 05 Dec 2014 13:36:36 -0500 Received: from mx1.redhat.com ([209.132.183.28]:44559) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Xwxjy-0002zL-CZ for qemu-devel@nongnu.org; Fri, 05 Dec 2014 13:36:30 -0500 From: Laszlo Ersek Date: Fri, 5 Dec 2014 19:36:13 +0100 Message-Id: <1417804575-19329-2-git-send-email-lersek@redhat.com> In-Reply-To: <1417804575-19329-1-git-send-email-lersek@redhat.com> References: <1417804575-19329-1-git-send-email-lersek@redhat.com> Subject: [Qemu-devel] [PATCH 1/3] hw/loader: split out load_image_gzipped_buffer() List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: rjones@redhat.com, crobinso@redhat.com, Peter Maydell , Drew Jones , Wei Huang , Ard Biesheuvel , qemu devel list , lersek@redhat.com In the next patch we'd like to reuse the image decompression facility without installing the output as a ROM at a specific guest-phys address. In addition, expose LOAD_IMAGE_MAX_GUNZIP_BYTES, because that's a straightforward "max_sz" argument for the new load_image_gzipped_buffer(). Signed-off-by: Laszlo Ersek --- include/hw/loader.h | 9 +++++++++ hw/core/loader.c | 30 +++++++++++++++++++++--------- 2 files changed, 30 insertions(+), 9 deletions(-) diff --git a/include/hw/loader.h b/include/hw/loader.h index 6481639..8997620 100644 --- a/include/hw/loader.h +++ b/include/hw/loader.h @@ -16,6 +16,15 @@ int load_image(const char *filename, uint8_t *addr); /* deprecated */ ssize_t load_image_size(const char *filename, void *addr, size_t size); int load_image_targphys(const char *filename, hwaddr, uint64_t max_sz); + +/* This is the limit on the maximum uncompressed image size that + * load_image_gzipped_buffer() and load_image_gzipped() will read. It prevents + * g_malloc() in those functions from allocating a huge amount of memory. + */ +#define LOAD_IMAGE_MAX_GUNZIP_BYTES (256 << 20) + +int load_image_gzipped_buffer(const char *filename, uint64_t max_sz, + uint8_t **buffer); int load_image_gzipped(const char *filename, hwaddr addr, uint64_t max_sz); #define ELF_LOAD_FAILED -1 diff --git a/hw/core/loader.c b/hw/core/loader.c index 7527fd3..933ab64 100644 --- a/hw/core/loader.c +++ b/hw/core/loader.c @@ -614,14 +614,9 @@ int load_ramdisk(const char *filename, hwaddr addr, uint64_t max_sz) NULL, NULL); } -/* This simply prevents g_malloc in the function below from allocating - * a huge amount of memory, by placing a limit on the maximum - * uncompressed image size that load_image_gzipped will read. - */ -#define LOAD_IMAGE_MAX_GUNZIP_BYTES (256 << 20) - -/* Load a gzip-compressed kernel. */ -int load_image_gzipped(const char *filename, hwaddr addr, uint64_t max_sz) +/* Load a gzip-compressed kernel to a dynamically allocated buffer. */ +int load_image_gzipped_buffer(const char *filename, uint64_t max_sz, + uint8_t **buffer) { uint8_t *compressed_data = NULL; uint8_t *data = NULL; @@ -653,8 +648,11 @@ int load_image_gzipped(const char *filename, hwaddr addr, uint64_t max_sz) goto out; } - rom_add_blob_fixed(filename, data, bytes, addr); + /* trim to actual size and return to caller */ + *buffer = g_realloc(data, bytes); ret = bytes; + /* ownership has been transferred to caller */ + data = NULL; out: g_free(compressed_data); @@ -662,6 +660,20 @@ int load_image_gzipped(const char *filename, hwaddr addr, uint64_t max_sz) return ret; } +/* Load a gzip-compressed kernel. */ +int load_image_gzipped(const char *filename, hwaddr addr, uint64_t max_sz) +{ + int bytes; + uint8_t *data; + + bytes = load_image_gzipped_buffer (filename, max_sz, &data); + if (bytes != -1) { + rom_add_blob_fixed(filename, data, bytes, addr); + g_free(data); + } + return bytes; +} + /* * Functions for reboot-persistent memory regions. * - used for vga bios and option roms. -- 1.8.3.1