CVSROOT: /cvs/dm Module name: multipath-tools Branch: RHEL4_FC5 Changes by: bmarzins@xxxxxxxxxxxxxx 2007-07-26 19:27:14 Modified files: libcheckers : directio.c Log message: Fix for #235081. Now using async directio callout. Patches: http://sourceware.org/cgi-bin/cvsweb.cgi/multipath-tools/libcheckers/directio.c.diff?cvsroot=dm&only_with_tag=RHEL4_FC5&r1=1.2&r2=1.2.2.1 --- multipath-tools/libcheckers/directio.c 2005/11/16 20:24:57 1.2 +++ multipath-tools/libcheckers/directio.c 2007/07/26 19:27:13 1.2.2.1 @@ -12,90 +12,149 @@ #include <sys/ioctl.h> #include <linux/fs.h> #include <errno.h> +#include <linux/kdev_t.h> +#include <asm/unistd.h> +#include "libaio.h" #include "path_state.h" #include "checkers.h" +#include "../libmultipath/debug.h" #define MSG_DIRECTIO_UNKNOWN "directio checker is not available" #define MSG_DIRECTIO_UP "directio checker reports path is up" #define MSG_DIRECTIO_DOWN "directio checker reports path is down" -struct readsector0_checker_context { - void * dummy; +struct directio_context { + int running; + int blksize; + unsigned char * buf; + unsigned char * ptr; + io_context_t ioctx; + struct iocb io; }; static int -direct_read (int fd, unsigned char * buff, int size) +check_state(int fd, struct directio_context *ct) { long flags; int reset_flags = 0; - int res, retval; + struct timespec timeout = { .tv_sec = 2 }; + struct io_event event; + struct stat sb; + int rc = PATH_UNCHECKED; + long r; - flags = fcntl(fd,F_GETFL); - - if (flags < 0) { - return PATH_UNCHECKED; - } + flags = fcntl(fd, F_GETFL); + if (flags < 0) + goto out; if (!(flags & O_DIRECT)) { flags |= O_DIRECT; - if (fcntl(fd,F_SETFL,flags) < 0) { - return PATH_UNCHECKED; - } + if (fcntl(fd, F_SETFL, flags) < 0) + goto out; reset_flags = 1; } - while ( (res = read(fd,buff,size)) < 0 && errno == EINTR ); - if (res < 0) { - if (errno == EINVAL) { - /* O_DIRECT is not available */ - retval = PATH_UNCHECKED; - } else if (errno == ENOMEM) { - retval = PATH_UP; - } else { - retval = PATH_DOWN; + if (fstat(fd, &sb) == 0) { + condlog(4, "directio: called for %x", (unsigned) sb.st_rdev); + } + + if (!ct->running) { + struct iocb *ios[1] = { &ct->io }; + + condlog(3, "directio: starting new request"); + memset(&ct->io, 0, sizeof(struct iocb)); + io_prep_pread(&ct->io, fd, ct->ptr, ct->blksize, 0); + if (syscall(__NR_io_submit, ct->ioctx, 1, ios) != 1) { + condlog(3, "directio: io_submit error %i", errno); + rc = PATH_UNCHECKED; + goto out; } + } + ct->running = 1; + + r = syscall(__NR_io_getevents, ct->ioctx, 1L, 1L, &event, &timeout); + if (r < 1L) { + condlog(3, "directio: timeout r=%li errno=%i", r, errno); + rc = PATH_DOWN; } else { - retval = PATH_UP; + condlog(3, "directio: io finished %lu/%lu", event.res, + event.res2); + ct->running = 0; + rc = (event.res == ct->blksize) ? PATH_UP : PATH_DOWN; } - + +out: if (reset_flags) { flags &= ~O_DIRECT; /* No point in checking for errors */ - fcntl(fd,F_SETFL,flags); + fcntl(fd, F_SETFL, flags); } + return rc; +} - return retval; +void +cleanup_context (struct directio_context *ctxt) +{ + if (ctxt->buf) + free(ctxt->buf); + syscall(__NR_io_destroy, ctxt->ioctx); + free(ctxt); } extern int directio (int fd, char *msg, void **context) { - unsigned char *buf, *ptr; - struct readsector0_checker_context * ctxt = NULL; - unsigned long pgsize, numsect; - int ret, blksize; - - pgsize = getpagesize(); + struct directio_context * ctxt = NULL; + int ret; /* * caller passed in a context : use its address */ if (context) - ctxt = (struct readsector0_checker_context *) (*context); + ctxt = (struct directio_context *) (*context); /* * passed in context is uninitialized or volatile context : * initialize it */ if (!ctxt) { - ctxt = malloc(sizeof(struct readsector0_checker_context)); - memset(ctxt, 0, sizeof(struct readsector0_checker_context)); - + unsigned long pgsize = getpagesize(); + + ctxt = malloc(sizeof(struct directio_context)); if (!ctxt) { - MSG("cannot allocate context"); - return -1; + condlog(0, "cannot allocate context"); + goto fail; + } + memset(ctxt, 0, sizeof(struct directio_context)); + if (syscall(__NR_io_setup, 1, &ctxt->ioctx) != 0) { + condlog(0, "io_setup failed"); + goto fail; + } + if (ioctl(fd, BLKBSZGET, &ctxt->blksize) < 0) { + condlog(3, "cannot get blocksize, set default"); + ctxt->blksize = 512; } + if (ctxt->blksize > 4096) { + /* + * Sanity check for DASD; BSZGET is broken + */ + ctxt->blksize = 4096; + } + if (!ctxt->blksize){ + condlog(3, "blocksize is zero? Assuming path down\n"); + MSG(MSG_DIRECTIO_DOWN); + ret = PATH_DOWN; + goto out; + } + ctxt->buf = (unsigned char *)malloc(ctxt->blksize + pgsize); + if (!ctxt->buf){ + condlog(0, "cannot allocate context buffer\n"); + goto fail; + } + + ctxt->ptr = (unsigned char *) (((unsigned long)ctxt->buf + pgsize - 1) & (~(pgsize - 1))); + if (context) *context = ctxt; } @@ -104,41 +163,7 @@ ret = -1; goto out; } - - if (ioctl(fd, BLKGETSIZE, &numsect) < 0) { - MSG("cannot get number of sectors, set default"); - numsect = 0; - } - - if (ioctl(fd, BLKBSZGET, &blksize) < 0) { - MSG("cannot get blocksize, set default"); - blksize = 512; - } - - if (blksize > 4096) { - /* - * Sanity check for DASD; BSZGET is broken - */ - blksize = 4096; - } - - if (!blksize) { - /* - * Blocksize is 0, assume we can't write - * to this device. - */ - MSG(MSG_DIRECTIO_DOWN); - ret = PATH_DOWN; - goto out; - } - - buf = (unsigned char *)malloc(blksize + pgsize); - if (!buf){ - goto out; - } - ptr = (unsigned char *)(((unsigned long)buf + pgsize - 1) & - (~(pgsize - 1))); - ret = direct_read(fd, ptr, blksize); + ret = check_state(fd, ctxt); switch (ret) { @@ -154,7 +179,6 @@ default: break; } - free(buf); out: /* @@ -162,7 +186,13 @@ * free it */ if (!context) - free(ctxt); + cleanup_context(ctxt); return ret; +fail: + if (context) + *context = NULL; + if (ctxt) + cleanup_context(ctxt); + return -1; } -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
