Messages in this thread | | | From | "David F." <> | Date | Fri, 30 Jun 2017 16:10:56 -0700 | Subject | did vfs_read or something related to it get broken? |
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Hi,
I have a driver that reads data from a file that has worked from kernel 3.x up to 4.9.13. I haven't tried all the other 4.9's or 4.10, or 4.11.6 or earlier, but in 4.11.7 it's now broken and an error is returned. It's based on http://krishnamohanlinux.blogspot.com/2013/12/how-to-write-to-file-from-kernel-module.html
Is there a new requirement of some sort or did it get broken?
int driver_file_read(struct file *file, unsigned char *data, unsigned int size) { int ret; mm_segment_t oldfs;
// get file pointer loff_t pos = file->f_pos;
oldfs = get_fs(); set_fs(get_ds());
ret=vfs_read(file, data, size, &pos);
set_fs(oldfs);
// update file pointer file->f_pos=pos;
return (ret); }
struct file *driver_file_open(const char *path, int flags, int mode, int *err) { int ec=0; struct file *filp = NULL; filp=filp_open(path, flags, mode); if (IS_ERR(filp)) { ec=PTR_ERR(filp); filp=NULL; } // update callers error code if (err) { *err=ec; } // return pointer to file return (filp); }
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