Hi Luis,
Another question.
On 2020-05-12 5:33 p.m., Luis Chamberlain wrote:
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!
fw_opt is an existing enum which doesn't really act like an enum.
It is a series of BIT defines in an enum that are then OR'd together in
the (existing) code?
{
struct fw_priv *tmp;
+ unsigned int pread_flags;
spin_lock(&fwc->lock);
if (!(opt_flags & FW_OPT_NOCACHE)) {
Have a look here - enum used as series of flags.
@@ -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.
pread_flags is currently such. I will change to enum pread_opt.
/* 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.
Yes, will change to fw_priv->opt and use enum for this one.
You get the idea, I stopped reviewing after this.
Luis
