Add kernel_pread_file* support to kernel to allow for partial read of files with an offset into the file. Existing kernel_read_file functions call new kernel_pread_file functions with offset=0 and flags=KERNEL_PREAD_FLAG_WHOLE.

Signed-off-by: Scott Branden scott.branden@broadcom.com --- fs/exec.c | 77 ++++++++++++++++++++++++++++++++++++---------- include/linux/fs.h | 15 +++++++++ 2 files changed, 75 insertions(+), 17 deletions(-)

diff --git a/fs/exec.c b/fs/exec.c index db17be51b112..a38f8fb432fa 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -896,10 +896,14 @@ struct file *open_exec(const char *name) } EXPORT_SYMBOL(open_exec);

-int kernel_read_file(struct file *file, void **buf, loff_t *size, - loff_t max_size, enum kernel_read_file_id id) -{ - loff_t i_size, pos; +int kernel_pread_file(struct file *file, void **buf, loff_t *size, + loff_t pos, loff_t max_size, unsigned int flags, + enum kernel_read_file_id id) +{ + loff_t alloc_size; + loff_t buf_pos; + loff_t read_end; + loff_t i_size; ssize_t bytes = 0; int ret;

@@ -919,21 +923,31 @@ int kernel_read_file(struct file *file, void **buf, loff_t *size, ret = -EINVAL; goto out; } - if (i_size > SIZE_MAX || (max_size > 0 && i_size > max_size)) { + + /* Default read to end of file */ + read_end = i_size; + + /* Allow reading partial portion of file */ + if ((flags & KERNEL_PREAD_FLAG_PART) && + (i_size > (pos + max_size))) + read_end = pos + max_size; + + alloc_size = read_end - pos; + if (i_size > SIZE_MAX || (max_size > 0 && alloc_size > max_size)) { ret = -EFBIG; goto out; }

if (id != READING_FIRMWARE_PREALLOC_BUFFER) - *buf = vmalloc(i_size); + *buf = vmalloc(alloc_size); if (!*buf) { ret = -ENOMEM; goto out; }

- pos = 0; - while (pos < i_size) { - bytes = kernel_read(file, *buf + pos, i_size - pos, &pos); + buf_pos = 0; + while (pos < read_end) { + bytes = kernel_read(file, *buf + buf_pos, read_end - pos, &pos); if (bytes < 0) { ret = bytes; goto out_free; @@ -941,14 +955,16 @@ int kernel_read_file(struct file *file, void **buf, loff_t *size,

if (bytes == 0) break; + + buf_pos += bytes; }

- if (pos != i_size) { + if (pos != read_end) { ret = -EIO; goto out_free; }

- ret = security_kernel_post_read_file(file, *buf, i_size, id); + ret = security_kernel_post_read_file(file, *buf, alloc_size, id); if (!ret) *size = pos;

@@ -964,10 +980,20 @@ int kernel_read_file(struct file *file, void **buf, loff_t *size, allow_write_access(file); return ret; } +EXPORT_SYMBOL_GPL(kernel_pread_file); + +int kernel_read_file(struct file *file, void **buf, loff_t *size, + loff_t max_size, enum kernel_read_file_id id) +{ + return kernel_pread_file(file, buf, size, 0, max_size, + KERNEL_PREAD_FLAG_WHOLE, id); +} EXPORT_SYMBOL_GPL(kernel_read_file);

-int kernel_read_file_from_path(const char *path, void **buf, loff_t *size, - loff_t max_size, enum kernel_read_file_id id) +int kernel_pread_file_from_path(const char *path, void **buf, + loff_t *size, loff_t pos, + loff_t max_size, unsigned int flags, + enum kernel_read_file_id id) { struct file *file; int ret; @@ -979,14 +1005,23 @@ int kernel_read_file_from_path(const char *path, void **buf, loff_t *size, if (IS_ERR(file)) return PTR_ERR(file);

- ret = kernel_read_file(file, buf, size, max_size, id); + ret = kernel_pread_file(file, buf, size, pos, max_size, flags, id); fput(file); return ret; } +EXPORT_SYMBOL_GPL(kernel_pread_file_from_path); + +int kernel_read_file_from_path(const char *path, void **buf, loff_t *size, + loff_t max_size, enum kernel_read_file_id id) +{ + return kernel_pread_file_from_path(path, buf, size, 0, max_size, + KERNEL_PREAD_FLAG_WHOLE, id); +} EXPORT_SYMBOL_GPL(kernel_read_file_from_path);

-int kernel_read_file_from_fd(int fd, void **buf, loff_t *size, loff_t max_size, - enum kernel_read_file_id id) +int kernel_pread_file_from_fd(int fd, void **buf, loff_t *size, loff_t pos, + loff_t max_size, unsigned int flags, + enum kernel_read_file_id id) { struct fd f = fdget(fd); int ret = -EBADF; @@ -994,11 +1029,19 @@ int kernel_read_file_from_fd(int fd, void **buf, loff_t *size, loff_t max_size, if (!f.file) goto out;

- ret = kernel_read_file(f.file, buf, size, max_size, id); + ret = kernel_pread_file(f.file, buf, size, pos, max_size, flags, id); out: fdput(f); return ret; } +EXPORT_SYMBOL_GPL(kernel_pread_file_from_fd); + +int kernel_read_file_from_fd(int fd, void **buf, loff_t *size, loff_t max_size, + enum kernel_read_file_id id) +{ + return kernel_pread_file_from_fd(fd, buf, size, 0, max_size, + KERNEL_PREAD_FLAG_WHOLE, id); +} EXPORT_SYMBOL_GPL(kernel_read_file_from_fd);

ssize_t read_code(struct file *file, unsigned long addr, loff_t pos, size_t len) diff --git a/include/linux/fs.h b/include/linux/fs.h index 3cd4fe6b845e..8f39530cfcc2 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -3008,10 +3008,25 @@ static inline const char *kernel_read_file_id_str(enum kernel_read_file_id id) return kernel_read_file_str[id]; }

+/* Flags used by kernel_pread_file functions */ +#define KERNEL_PREAD_FLAG_WHOLE 0x0000 /* Only Allow reading of whole file */ +#define KERNEL_PREAD_FLAG_PART 0x0001 /* Allow reading part of file */ + +extern int kernel_pread_file(struct file *file, void **buf, loff_t *size, + loff_t pos, loff_t max_size, unsigned int flags, + enum kernel_read_file_id id); extern int kernel_read_file(struct file *, void **, loff_t *, loff_t, enum kernel_read_file_id); +extern int kernel_pread_file_from_path(const char *path, void **buf, + loff_t *size, loff_t pos, + loff_t max_size, unsigned int flags, + enum kernel_read_file_id id); extern int kernel_read_file_from_path(const char *, void **, loff_t *, loff_t, enum kernel_read_file_id); +extern int kernel_pread_file_from_fd(int fd, void **buf, loff_t *size, + loff_t pos, loff_t max_size, + unsigned int flags, + enum kernel_read_file_id id); extern int kernel_read_file_from_fd(int, void **, loff_t *, loff_t, enum kernel_read_file_id); extern ssize_t kernel_read(struct file *, void *, size_t, loff_t *);

Add additional hooks to test_firmware to pass in support for partial file read using request_firmware_into_buf. buf_size: size of buffer to request firmware into partial: indicates that a partial file request is being made file_offset: to indicate offset into file to request

Signed-off-by: Scott Branden scott.branden@broadcom.com --- lib/test_firmware.c | 141 +++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 138 insertions(+), 3 deletions(-)

diff --git a/lib/test_firmware.c b/lib/test_firmware.c index 7d1d97fa9a23..6050d3113f92 100644 --- a/lib/test_firmware.c +++ b/lib/test_firmware.c @@ -49,6 +49,9 @@ struct test_batched_req { * @name: the name of the firmware file to look for * @into_buf: when the into_buf is used if this is true * request_firmware_into_buf() will be used instead. + * @buf_size: size of buf to allocate when into_buf is true + * @file_offset: file offset to request when calling request_firmware_into_buf + * @partial: partial read flag value when calling request_firmware_into_buf * @sync_direct: when the sync trigger is used if this is true * request_firmware_direct() will be used instead. * @send_uevent: whether or not to send a uevent for async requests @@ -88,6 +91,9 @@ struct test_batched_req { struct test_config { char *name; bool into_buf; + size_t buf_size; + size_t file_offset; + bool partial; bool sync_direct; bool send_uevent; u8 num_requests; @@ -182,6 +188,9 @@ static int __test_firmware_config_init(void) test_fw_config->num_requests = TEST_FIRMWARE_NUM_REQS; test_fw_config->send_uevent = true; test_fw_config->into_buf = false; + test_fw_config->buf_size = TEST_FIRMWARE_BUF_SIZE; + test_fw_config->file_offset = 0; + test_fw_config->partial = false; test_fw_config->sync_direct = false; test_fw_config->req_firmware = request_firmware; test_fw_config->test_result = 0; @@ -253,6 +262,13 @@ static ssize_t config_show(struct device *dev, len += scnprintf(buf+len, PAGE_SIZE - len, "into_buf:\t\t%s\n", test_fw_config->into_buf ? "true" : "false"); + len += scnprintf(buf+len, PAGE_SIZE - len, + "buf_size:\t%zu\n", test_fw_config->buf_size); + len += scnprintf(buf+len, PAGE_SIZE - len, + "file_offset:\t%zu\n", test_fw_config->file_offset); + len += scnprintf(buf+len, PAGE_SIZE - len, + "partial:\t\t%s\n", + test_fw_config->partial ? "true" : "false"); len += scnprintf(buf+len, PAGE_SIZE - len, "sync_direct:\t\t%s\n", test_fw_config->sync_direct ? "true" : "false"); @@ -322,6 +338,39 @@ test_dev_config_show_bool(char *buf, return snprintf(buf, PAGE_SIZE, "%d\n", val); }

+static int test_dev_config_update_size_t(const char *buf, + size_t size, + size_t *cfg) +{ + int ret; + long new; + + ret = kstrtol(buf, 10, &new); + if (ret) + return ret; + + if (new > SIZE_MAX) + return -EINVAL; + + mutex_lock(&test_fw_mutex); + *(size_t *)cfg = new; + mutex_unlock(&test_fw_mutex); + + /* Always return full write size even if we didn't consume all */ + return size; +} + +static ssize_t test_dev_config_show_size_t(char *buf, int cfg) +{ + size_t val; + + mutex_lock(&test_fw_mutex); + val = cfg; + mutex_unlock(&test_fw_mutex); + + return snprintf(buf, PAGE_SIZE, "%zu\n", val); +} + static ssize_t test_dev_config_show_int(char *buf, int cfg) { int val; @@ -419,6 +468,83 @@ static ssize_t config_into_buf_show(struct device *dev, } static DEVICE_ATTR_RW(config_into_buf);

+static ssize_t config_buf_size_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + int rc; + + mutex_lock(&test_fw_mutex); + if (test_fw_config->reqs) { + pr_err("Must call release_all_firmware prior to changing config\n"); + rc = -EINVAL; + mutex_unlock(&test_fw_mutex); + goto out; + } + mutex_unlock(&test_fw_mutex); + + rc = test_dev_config_update_size_t(buf, count, + &test_fw_config->buf_size); + +out: + return rc; +} + +static ssize_t config_buf_size_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + return test_dev_config_show_size_t(buf, test_fw_config->buf_size); +} +static DEVICE_ATTR_RW(config_buf_size); + +static ssize_t config_file_offset_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + int rc; + + mutex_lock(&test_fw_mutex); + if (test_fw_config->reqs) { + pr_err("Must call release_all_firmware prior to changing config\n"); + rc = -EINVAL; + mutex_unlock(&test_fw_mutex); + goto out; + } + mutex_unlock(&test_fw_mutex); + + rc = test_dev_config_update_size_t(buf, count, + &test_fw_config->file_offset); + +out: + return rc; +} + +static ssize_t config_file_offset_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + return test_dev_config_show_size_t(buf, test_fw_config->file_offset); +} +static DEVICE_ATTR_RW(config_file_offset); + +static ssize_t config_partial_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + return test_dev_config_update_bool(buf, + count, + &test_fw_config->partial); +} + +static ssize_t config_partial_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + return test_dev_config_show_bool(buf, test_fw_config->partial); +} +static DEVICE_ATTR_RW(config_partial); + static ssize_t config_sync_direct_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) @@ -613,18 +739,24 @@ static int test_fw_run_batch_request(void *data)

if (test_fw_config->into_buf) { void *test_buf; + unsigned int pread_flags;

test_buf = kzalloc(TEST_FIRMWARE_BUF_SIZE, GFP_KERNEL); if (!test_buf) return -ENOSPC;

+ if (test_fw_config->partial) + pread_flags = KERNEL_PREAD_FLAG_PART; + else + pread_flags = KERNEL_PREAD_FLAG_WHOLE; + req->rc = request_firmware_into_buf(&req->fw, req->name, req->dev, test_buf, - TEST_FIRMWARE_BUF_SIZE, - 0, - KERNEL_PREAD_FLAG_WHOLE); + test_fw_config->buf_size, + test_fw_config->file_offset, + pread_flags); if (!req->fw) kfree(test_buf); } else { @@ -897,6 +1029,9 @@ static struct attribute *test_dev_attrs[] = { TEST_FW_DEV_ATTR(config_name), TEST_FW_DEV_ATTR(config_num_requests), TEST_FW_DEV_ATTR(config_into_buf), + TEST_FW_DEV_ATTR(config_buf_size), + TEST_FW_DEV_ATTR(config_file_offset), + TEST_FW_DEV_ATTR(config_partial), TEST_FW_DEV_ATTR(config_sync_direct), TEST_FW_DEV_ATTR(config_send_uevent), TEST_FW_DEV_ATTR(config_read_fw_idx),

Add firmware tests for partial file reads of request_firmware_into_buf.

Signed-off-by: Scott Branden scott.branden@broadcom.com --- .../selftests/firmware/fw_filesystem.sh | 80 +++++++++++++++++++ 1 file changed, 80 insertions(+)

diff --git a/tools/testing/selftests/firmware/fw_filesystem.sh b/tools/testing/selftests/firmware/fw_filesystem.sh index 56894477c8bd..e973c658fe1a 100755 --- a/tools/testing/selftests/firmware/fw_filesystem.sh +++ b/tools/testing/selftests/firmware/fw_filesystem.sh @@ -126,6 +126,26 @@ config_unset_into_buf() echo 0 > $DIR/config_into_buf }

+config_set_buf_size() +{ + echo $1 > $DIR/config_buf_size +} + +config_set_file_offset() +{ + echo $1 > $DIR/config_file_offset +} + +config_set_partial() +{ + echo 1 > $DIR/config_partial +} + +config_unset_partial() +{ + echo 0 > $DIR/config_partial +} + config_set_sync_direct() { echo 1 > $DIR/config_sync_direct @@ -184,6 +204,35 @@ read_firmwares() done }

+read_firmwares_partial() +{ + if [ "$(cat $DIR/config_into_buf)" == "1" ]; then + fwfile="${FW_INTO_BUF}" + else + fwfile="${FW}" + fi + + if [ "$1" = "xzonly" ]; then + fwfile="${fwfile}-orig" + fi + + # Strip fwfile down to match partial offset and length + partial_data="$(cat $fwfile)" + partial_data="${partial_data:$2:$3}" + + for i in $(seq 0 3); do + config_set_read_fw_idx $i + + read_firmware="$(cat $DIR/read_firmware)" + + # Verify the contents are what we expect. + if [ $read_firmware != $partial_data ]; then + echo "request #$i: partial firmware was not loaded" >&2 + exit 1 + fi + done +} + read_firmwares_expect_nofile() { for i in $(seq 0 3); do @@ -296,6 +345,21 @@ test_batched_request_firmware_into_buf() echo "OK" }

+test_batched_request_firmware_into_buf_partial() +{ + echo -n "Batched request_firmware_into_buf_partial() $2 off=$3 size=$4 try #$1: " + config_reset + config_set_name $TEST_FIRMWARE_INTO_BUF_FILENAME + config_set_into_buf + config_set_partial + config_set_buf_size $4 + config_set_file_offset $3 + config_trigger_sync + read_firmwares_partial $2 $3 $4 + release_all_firmware + echo "OK" +} + test_batched_request_firmware_direct() { echo -n "Batched request_firmware_direct() $2 try #$1: " @@ -348,6 +412,22 @@ for i in $(seq 1 5); do test_batched_request_firmware_into_buf $i normal done

+for i in $(seq 1 5); do + test_batched_request_firmware_into_buf_partial $i normal 0 10 +done + +for i in $(seq 1 5); do + test_batched_request_firmware_into_buf_partial $i normal 0 5 +done + +for i in $(seq 1 5); do + test_batched_request_firmware_into_buf_partial $i normal 1 6 +done + +for i in $(seq 1 5); do + test_batched_request_firmware_into_buf_partial $i normal 2 10 +done + for i in $(seq 1 5); do test_batched_request_firmware_direct $i normal done