On Thu, May 07, 2020 at 05:27:34PM -0700, Scott Branden wrote: > Add offset to request_firmware_into_buf to allow for portions > of firmware file to be read into a buffer. Necessary where firmware > needs to be loaded in portions from file in memory constrained systems. > > Signed-off-by: Scott Branden <scott.bran...@broadcom.com> > --- > drivers/base/firmware_loader/firmware.h | 5 +++ > drivers/base/firmware_loader/main.c | 52 +++++++++++++++++-------- > drivers/soc/qcom/mdt_loader.c | 7 +++- > include/linux/firmware.h | 8 +++- > lib/test_firmware.c | 4 +- > 5 files changed, 55 insertions(+), 21 deletions(-) > > diff --git a/drivers/base/firmware_loader/firmware.h > b/drivers/base/firmware_loader/firmware.h > index 25836a6afc9f..1147dae01148 100644 > --- a/drivers/base/firmware_loader/firmware.h > +++ b/drivers/base/firmware_loader/firmware.h > @@ -32,6 +32,8 @@ > * @FW_OPT_FALLBACK_PLATFORM: Enable fallback to device fw copy embedded in > * the platform's main firmware. If both this fallback and the sysfs > * fallback are enabled, then this fallback will be tried first. > + * @FW_OPT_PARTIAL: Allow partial read of firmware instead of needing to read > + * entire file.
See, this allows us use kdoc to document his nicely. Do that with the kernel pread stuff. > @@ -68,6 +71,8 @@ struct fw_priv { > void *data; > size_t size; > size_t allocated_size; > + size_t offset; > + unsigned int flags; But flags is a misnomer, you just do two operations, just juse an enum here to classify the read operation. > index 76f79913916d..4552b7bb819f 100644 > --- a/drivers/base/firmware_loader/main.c > +++ b/drivers/base/firmware_loader/main.c > @@ -167,7 +167,8 @@ static int fw_cache_piggyback_on_request(const char > *name); > > static struct fw_priv *__allocate_fw_priv(const char *fw_name, > struct firmware_cache *fwc, > - void *dbuf, size_t size) > + void *dbuf, size_t size, > + size_t offset, unsigned int flags) And likewise just use an enum here too. > @@ -210,9 +213,11 @@ static struct fw_priv *__lookup_fw_priv(const char > *fw_name) > static int alloc_lookup_fw_priv(const char *fw_name, > struct firmware_cache *fwc, > struct fw_priv **fw_priv, void *dbuf, > - size_t size, enum fw_opt opt_flags) > + size_t size, enum fw_opt opt_flags, > + size_t offset) flags? But its a single variable enum! > { > struct fw_priv *tmp; > + unsigned int pread_flags; > > spin_lock(&fwc->lock); > if (!(opt_flags & FW_OPT_NOCACHE)) { > @@ -226,7 +231,12 @@ static int alloc_lookup_fw_priv(const char *fw_name, > } > } > > - tmp = __allocate_fw_priv(fw_name, fwc, dbuf, size); > + if (opt_flags & FW_OPT_PARTIAL) > + pread_flags = KERNEL_PREAD_FLAG_PART; > + else > + pread_flags = KERNEL_PREAD_FLAG_WHOLE; > + > + tmp = __allocate_fw_priv(fw_name, fwc, dbuf, size, offset, pread_flags); One of the advantages of using an enum is that you can then use a switch here, and the compiler will warn if you haven't handled all the cases. > /* load firmware files from the mount namespace of init */ > - rc = kernel_read_file_from_path_initns(path, &buffer, > - &size, msize, id); > + rc = kernel_pread_file_from_path_initns(path, &buffer, > + &size, fw_priv->offset, > + msize, > + fw_priv->flags, id); And here you'd just pass the kernel enum. You get the idea, I stopped reviewing after this. Luis