On Thu, Mar 7, 2013 at 12:10 PM, Swâmi Petaramesh <sw...@petaramesh.org> wrote: > Le 07/03/2013 19:06, Jérôme Poulin a écrit : >> mkfs.btrfs tries to lookup loop devices by their filenames and fails >> if any loop device file is missing. > > Hmm.... Why would mkfs.btrfs want to lookup anything else but the device > we're trying to format, to check if it's mounted or not ? >
At Sabayon, we pretty-much hacked our way around this with a "make-it-go" kind of patch. Otherwise, our installation would break with btrfs on our Live-[CD/DVD/USB] media. I know we should have taken the time to put together a proper solution, but I could never figure out the reasoning for needing to scan every device either. --- btrfs-progs-0.19.orig/utils.c +++ btrfs-progs-0.19/utils.c @@ -708,6 +708,21 @@ int is_same_blk_file(const char* a, cons return 0; } +/* Checks if a file exists and is a block or regular file*/ +int is_existing_blk_or_reg_file(const char* filename) +{ + struct stat st_buf; + + if(stat(filename, &st_buf) < 0) { + if(errno == ENOENT) + return 0; + else + return -errno; + } + + return (S_ISBLK(st_buf.st_mode) || S_ISREG(st_buf.st_mode)); +} + /* checks if a and b are identical or device * files associated with the same block device or * if one file is a loop device that uses the other @@ -727,7 +742,10 @@ int is_same_loop_file(const char* a, con } else if(ret) { if((ret = resolve_loop_device(a, res_a, sizeof(res_a))) < 0) return ret; - + /* if the resolved path is not available, there is nothing + we can do */ + if((ret = is_existing_blk_or_reg_file(res_a)) == 0) + return ret; final_a = res_a; } else { final_a = a; @@ -739,6 +757,10 @@ int is_same_loop_file(const char* a, con } else if(ret) { if((ret = resolve_loop_device(b, res_b, sizeof(res_b))) < 0) return ret; + /* if the resolved path is not available, there is nothing + we can do */ + if((ret = is_existing_blk_or_reg_file(res_b)) == 0) + return ret; final_b = res_b; } else { @@ -748,21 +770,6 @@ int is_same_loop_file(const char* a, con return is_same_blk_file(final_a, final_b); } -/* Checks if a file exists and is a block or regular file*/ -int is_existing_blk_or_reg_file(const char* filename) -{ - struct stat st_buf; - - if(stat(filename, &st_buf) < 0) { - if(errno == ENOENT) - return 0; - else - return -errno; - } - - return (S_ISBLK(st_buf.st_mode) || S_ISREG(st_buf.st_mode)); -} - /* Checks if a file is used (directly or indirectly via a loop device) * by a device in fs_devices */ -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html