| Message ID | 20240628182706.99525-1-gregorhaas1997@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v4] hw/core/loader: allow loading larger ROMs | expand |
On Fri, Jun 28, 2024 at 11:27:06AM -0700, Gregor Haas wrote: > The read() syscall is not guaranteed to return all data from a file. The > default ROM loader implementation currently does not take this into account, > instead failing if all bytes are not read at once. This change loads the ROM > using g_file_get_contents() instead, which correctly reads all data using > multiple calls to read() while also returning the loaded ROM size. > > Signed-off-by: Gregor Haas <gregorhaas1997@gmail.com> > --- > hw/core/loader.c | 30 +++++------------------------- > 1 file changed, 5 insertions(+), 25 deletions(-) Reviewed-by: Daniel P. Berrangé <berrange@redhat.com> With regards, Daniel
Reviewed-by: Xingtao Yao <yaoxt.fnst@fujitsu.com> > -----Original Message----- > From: Gregor Haas <gregorhaas1997@gmail.com> > Sent: Saturday, June 29, 2024 2:27 AM > To: qemu-devel@nongnu.org > Cc: berrange@redhat.com; Yao, Xingtao/姚 幸涛 <yaoxt.fnst@fujitsu.com>; > Gregor Haas <gregorhaas1997@gmail.com> > Subject: [PATCH v4] hw/core/loader: allow loading larger ROMs > > The read() syscall is not guaranteed to return all data from a file. The > default ROM loader implementation currently does not take this into account, > instead failing if all bytes are not read at once. This change loads the ROM > using g_file_get_contents() instead, which correctly reads all data using > multiple calls to read() while also returning the loaded ROM size. > > Signed-off-by: Gregor Haas <gregorhaas1997@gmail.com> > --- > hw/core/loader.c | 30 +++++------------------------- > 1 file changed, 5 insertions(+), 25 deletions(-) > > diff --git a/hw/core/loader.c b/hw/core/loader.c > index 2f8105d7de..44444a5714 100644 > --- a/hw/core/loader.c > +++ b/hw/core/loader.c > @@ -1075,8 +1075,7 @@ ssize_t rom_add_file(const char *file, const char *fw_dir, > { > MachineClass *mc = MACHINE_GET_CLASS(qdev_get_machine()); > Rom *rom; > - ssize_t rc; > - int fd = -1; > + g_autoptr(GError) gerr = NULL; > char devpath[100]; > > if (as && mr) { > @@ -1094,35 +1093,19 @@ ssize_t rom_add_file(const char *file, const char > *fw_dir, > rom->path = g_strdup(file); > } > > - fd = open(rom->path, O_RDONLY | O_BINARY); > - if (fd == -1) { > - fprintf(stderr, "Could not open option rom '%s': %s\n", > - rom->path, strerror(errno)); > - goto err; > - } > - > if (fw_dir) { > rom->fw_dir = g_strdup(fw_dir); > rom->fw_file = g_strdup(file); > } > rom->addr = addr; > - rom->romsize = lseek(fd, 0, SEEK_END); > - if (rom->romsize == -1) { > - fprintf(stderr, "rom: file %-20s: get size error: %s\n", > - rom->name, strerror(errno)); > + if (!g_file_get_contents(rom->path, (gchar **) &rom->data, > + &rom->romsize, &gerr)) { > + fprintf(stderr, "rom: file %-20s: error %s\n", > + rom->name, gerr->message); > goto err; > } > > rom->datasize = rom->romsize; > - rom->data = g_malloc0(rom->datasize); > - lseek(fd, 0, SEEK_SET); > - rc = read(fd, rom->data, rom->datasize); > - if (rc != rom->datasize) { > - fprintf(stderr, "rom: file %-20s: read error: rc=%zd (expected %zd)\n", > - rom->name, rc, rom->datasize); > - goto err; > - } > - close(fd); > rom_insert(rom); > if (rom->fw_file && fw_cfg) { > const char *basename; > @@ -1159,9 +1142,6 @@ ssize_t rom_add_file(const char *file, const char *fw_dir, > return 0; > > err: > - if (fd != -1) > - close(fd); > - > rom_free(rom); > return -1; > } > -- > 2.45.2
On 28/6/24 20:27, Gregor Haas wrote: > The read() syscall is not guaranteed to return all data from a file. The > default ROM loader implementation currently does not take this into account, > instead failing if all bytes are not read at once. This change loads the ROM > using g_file_get_contents() instead, which correctly reads all data using > multiple calls to read() while also returning the loaded ROM size. > > Signed-off-by: Gregor Haas <gregorhaas1997@gmail.com> > --- > hw/core/loader.c | 30 +++++------------------------- > 1 file changed, 5 insertions(+), 25 deletions(-) Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> and queued, thanks!
diff --git a/hw/core/loader.c b/hw/core/loader.c index 2f8105d7de..44444a5714 100644 --- a/hw/core/loader.c +++ b/hw/core/loader.c @@ -1075,8 +1075,7 @@ ssize_t rom_add_file(const char *file, const char *fw_dir, { MachineClass *mc = MACHINE_GET_CLASS(qdev_get_machine()); Rom *rom; - ssize_t rc; - int fd = -1; + g_autoptr(GError) gerr = NULL; char devpath[100]; if (as && mr) { @@ -1094,35 +1093,19 @@ ssize_t rom_add_file(const char *file, const char *fw_dir, rom->path = g_strdup(file); } - fd = open(rom->path, O_RDONLY | O_BINARY); - if (fd == -1) { - fprintf(stderr, "Could not open option rom '%s': %s\n", - rom->path, strerror(errno)); - goto err; - } - if (fw_dir) { rom->fw_dir = g_strdup(fw_dir); rom->fw_file = g_strdup(file); } rom->addr = addr; - rom->romsize = lseek(fd, 0, SEEK_END); - if (rom->romsize == -1) { - fprintf(stderr, "rom: file %-20s: get size error: %s\n", - rom->name, strerror(errno)); + if (!g_file_get_contents(rom->path, (gchar **) &rom->data, + &rom->romsize, &gerr)) { + fprintf(stderr, "rom: file %-20s: error %s\n", + rom->name, gerr->message); goto err; } rom->datasize = rom->romsize; - rom->data = g_malloc0(rom->datasize); - lseek(fd, 0, SEEK_SET); - rc = read(fd, rom->data, rom->datasize); - if (rc != rom->datasize) { - fprintf(stderr, "rom: file %-20s: read error: rc=%zd (expected %zd)\n", - rom->name, rc, rom->datasize); - goto err; - } - close(fd); rom_insert(rom); if (rom->fw_file && fw_cfg) { const char *basename; @@ -1159,9 +1142,6 @@ ssize_t rom_add_file(const char *file, const char *fw_dir, return 0; err: - if (fd != -1) - close(fd); - rom_free(rom); return -1; }
The read() syscall is not guaranteed to return all data from a file. The default ROM loader implementation currently does not take this into account, instead failing if all bytes are not read at once. This change loads the ROM using g_file_get_contents() instead, which correctly reads all data using multiple calls to read() while also returning the loaded ROM size. Signed-off-by: Gregor Haas <gregorhaas1997@gmail.com> --- hw/core/loader.c | 30 +++++------------------------- 1 file changed, 5 insertions(+), 25 deletions(-)