From 86d4bcbdcbf91717a62797494be40a18d1e43d6d Mon Sep 17 00:00:00 2001 From: Cyril Bur Date: Thu, 20 Apr 2017 15:39:44 +1000 Subject: libflash/file: Only use 64bit MTD erase ioctl() when needed We recently made MTD 64 bit safe in e5720d3fe94 which now requires the 64 bit MTD erase ioctl. Unfortunately this ioctl is not present in older kernels used by some BMC vendors that use pflash. This patch addresses this by only using the 64bit version of the erase ioctl() if the parameters exceed 32bit in size. If an erase requires the 64bit ioctl() on a kernel which does not support it, the code will still attempt it. There is no way of knowing beforehand if the kernel supports it. The ioctl() will fail and an error will be returned from from the function. Signed-off-by: Cyril Bur Signed-off-by: Michael Neuling --- libflash/file.c | 44 ++++++++++++++++++++++++++++++++++++++------ 1 file changed, 38 insertions(+), 6 deletions(-) (limited to 'libflash') diff --git a/libflash/file.c b/libflash/file.c index 5f074cf..8d1ed02 100644 --- a/libflash/file.c +++ b/libflash/file.c @@ -15,6 +15,7 @@ */ #define _GNU_SOURCE #include +#include #include #include #include @@ -130,13 +131,44 @@ static int file_erase(struct blocklevel_device *bl, uint64_t dst, uint64_t len) static int mtd_erase(struct blocklevel_device *bl, uint64_t dst, uint64_t len) { struct file_data *file_data = container_of(bl, struct file_data, bl); - struct erase_info_user64 erase_info = { - .start = dst, - .length = len - }; + int err; - if (ioctl(file_data->fd, MEMERASE64, &erase_info) == -1) - return FLASH_ERR_PARM_ERROR; + FL_DBG("%s: dst: 0x%" PRIx64 ", len: 0x%" PRIx64 "\n", __func__, dst, len); + + /* + * Some kernels that pflash supports do not know about the 64bit + * version of the ioctl() therefore we'll just use the 32bit (which + * should always be supported...) unless we MUST use the 64bit and + * then lets just hope the kernel knows how to deal with it. If it + * is unsupported the ioctl() will fail and we'll report that - + * there is no other option. + */ + if (dst > UINT_MAX || len > UINT_MAX) { + struct erase_info_user64 erase_info = { + .start = dst, + .length = len + }; + + if (ioctl(file_data->fd, MEMERASE64, &erase_info) == -1) { + err = errno; + if (err == 25) /* Kernel doesn't do 64bit MTD erase ioctl() */ + FL_DBG("Attempted a 64bit erase on a kernel which doesn't support it\n"); + FL_ERR("%s: IOCTL to kernel failed! %s\n", __func__, strerror(err)); + errno = err; + return FLASH_ERR_PARM_ERROR; + } + } else { + struct erase_info_user erase_info = { + .start = dst, + .length = len + }; + if (ioctl(file_data->fd, MEMERASE, &erase_info) == -1) { + err = errno; + FL_ERR("%s: IOCTL to kernel failed! %s\n", __func__, strerror(err)); + errno = err; + return FLASH_ERR_PARM_ERROR; + } + } return 0; } -- cgit v1.1