diff options
Diffstat (limited to 'fs/gfs2/lock_dlm.c')
| -rw-r--r-- | fs/gfs2/lock_dlm.c | 240 |
1 files changed, 240 insertions, 0 deletions
diff --git a/fs/gfs2/lock_dlm.c b/fs/gfs2/lock_dlm.c new file mode 100644 index 0000000..a0bb7d2 --- /dev/null +++ b/fs/gfs2/lock_dlm.c @@ -0,0 +1,240 @@ +/* + * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. + * Copyright (C) 2004-2009 Red Hat, Inc. All rights reserved. + * + * This copyrighted material is made available to anyone wishing to use, + * modify, copy, or redistribute it subject to the terms and conditions + * of the GNU General Public License version 2. + */ + +#include <linux/fs.h> +#include <linux/dlm.h> +#include <linux/types.h> +#include <linux/gfs2_ondisk.h> + +#include "incore.h" +#include "glock.h" +#include "util.h" + + +static void gdlm_ast(void *arg) +{ + struct gfs2_glock *gl = arg; + unsigned ret = gl->gl_state; + + BUG_ON(gl->gl_lksb.sb_flags & DLM_SBF_DEMOTED); + + if (gl->gl_lksb.sb_flags & DLM_SBF_VALNOTVALID) + memset(gl->gl_lvb, 0, GDLM_LVB_SIZE); + + switch (gl->gl_lksb.sb_status) { + case -DLM_EUNLOCK: /* Unlocked, so glock can be freed */ + kmem_cache_free(gfs2_glock_cachep, gl); + return; + case -DLM_ECANCEL: /* Cancel while getting lock */ + ret |= LM_OUT_CANCELED; + goto out; + case -EAGAIN: /* Try lock fails */ + goto out; + case -EINVAL: /* Invalid */ + case -ENOMEM: /* Out of memory */ + ret |= LM_OUT_ERROR; + goto out; + case 0: /* Success */ + break; + default: /* Something unexpected */ + BUG(); + } + + ret = gl->gl_target; + if (gl->gl_lksb.sb_flags & DLM_SBF_ALTMODE) { + if (gl->gl_target == LM_ST_SHARED) + ret = LM_ST_DEFERRED; + else if (gl->gl_target == LM_ST_DEFERRED) + ret = LM_ST_SHARED; + else + BUG(); + } + + set_bit(GLF_INITIAL, &gl->gl_flags); + gfs2_glock_complete(gl, ret); + return; +out: + if (!test_bit(GLF_INITIAL, &gl->gl_flags)) + gl->gl_lksb.sb_lkid = 0; + gfs2_glock_complete(gl, ret); +} + +static void gdlm_bast(void *arg, int mode) +{ + struct gfs2_glock *gl = arg; + + switch (mode) { + case DLM_LOCK_EX: + gfs2_glock_cb(gl, LM_ST_UNLOCKED); + break; + case DLM_LOCK_CW: + gfs2_glock_cb(gl, LM_ST_DEFERRED); + break; + case DLM_LOCK_PR: + gfs2_glock_cb(gl, LM_ST_SHARED); + break; + default: + printk(KERN_ERR "unknown bast mode %d", mode); + BUG(); + } +} + +/* convert gfs lock-state to dlm lock-mode */ + +static int make_mode(const unsigned int lmstate) +{ + switch (lmstate) { + case LM_ST_UNLOCKED: + return DLM_LOCK_NL; + case LM_ST_EXCLUSIVE: + return DLM_LOCK_EX; + case LM_ST_DEFERRED: + return DLM_LOCK_CW; + case LM_ST_SHARED: + return DLM_LOCK_PR; + } + printk(KERN_ERR "unknown LM state %d", lmstate); + BUG(); + return -1; +} + +static u32 make_flags(const u32 lkid, const unsigned int gfs_flags, + const int req) +{ + u32 lkf = 0; + + if (gfs_flags & LM_FLAG_TRY) + lkf |= DLM_LKF_NOQUEUE; + + if (gfs_flags & LM_FLAG_TRY_1CB) { + lkf |= DLM_LKF_NOQUEUE; + lkf |= DLM_LKF_NOQUEUEBAST; + } + + if (gfs_flags & LM_FLAG_PRIORITY) { + lkf |= DLM_LKF_NOORDER; + lkf |= DLM_LKF_HEADQUE; + } + + if (gfs_flags & LM_FLAG_ANY) { + if (req == DLM_LOCK_PR) + lkf |= DLM_LKF_ALTCW; + else if (req == DLM_LOCK_CW) + lkf |= DLM_LKF_ALTPR; + else + BUG(); + } + + if (lkid != 0) + lkf |= DLM_LKF_CONVERT; + + lkf |= DLM_LKF_VALBLK; + + return lkf; +} + +static unsigned int gdlm_lock(struct gfs2_glock *gl, + unsigned int req_state, unsigned int flags) +{ + struct lm_lockstruct *ls = &gl->gl_sbd->sd_lockstruct; + int error; + int req; + u32 lkf; + + req = make_mode(req_state); + lkf = make_flags(gl->gl_lksb.sb_lkid, flags, req); + + /* + * Submit the actual lock request. + */ + + error = dlm_lock(ls->ls_dlm, req, &gl->gl_lksb, lkf, gl->gl_strname, + GDLM_STRNAME_BYTES - 1, 0, gdlm_ast, gl, gdlm_bast); + if (error == -EAGAIN) + return 0; + if (error) + return LM_OUT_ERROR; + return LM_OUT_ASYNC; +} + +static void gdlm_put_lock(struct kmem_cache *cachep, void *ptr) +{ + struct gfs2_glock *gl = ptr; + struct lm_lockstruct *ls = &gl->gl_sbd->sd_lockstruct; + int error; + + if (gl->gl_lksb.sb_lkid == 0) { + kmem_cache_free(cachep, gl); + return; + } + + error = dlm_unlock(ls->ls_dlm, gl->gl_lksb.sb_lkid, DLM_LKF_VALBLK, + NULL, gl); + if (error) { + printk(KERN_ERR "gdlm_unlock %x,%llx err=%d\n", + gl->gl_name.ln_type, + (unsigned long long)gl->gl_name.ln_number, error); + return; + } +} + +static void gdlm_cancel(struct gfs2_glock *gl) +{ + struct lm_lockstruct *ls = &gl->gl_sbd->sd_lockstruct; + dlm_unlock(ls->ls_dlm, gl->gl_lksb.sb_lkid, DLM_LKF_CANCEL, NULL, gl); +} + +static int gdlm_mount(struct gfs2_sbd *sdp, const char *fsname) +{ + struct lm_lockstruct *ls = &sdp->sd_lockstruct; + int error; + + if (fsname == NULL) { + fs_info(sdp, "no fsname found\n"); + return -EINVAL; + } + + error = dlm_new_lockspace(fsname, strlen(fsname), &ls->ls_dlm, + DLM_LSFL_FS | DLM_LSFL_NEWEXCL | + (ls->ls_nodir ? DLM_LSFL_NODIR : 0), + GDLM_LVB_SIZE); + if (error) + printk(KERN_ERR "dlm_new_lockspace error %d", error); + + return error; +} + +static void gdlm_unmount(struct gfs2_sbd *sdp) +{ + struct lm_lockstruct *ls = &sdp->sd_lockstruct; + + if (ls->ls_dlm) { + dlm_release_lockspace(ls->ls_dlm, 2); + ls->ls_dlm = NULL; + } +} + +static const match_table_t dlm_tokens = { + { Opt_jid, "jid=%d"}, + { Opt_id, "id=%d"}, + { Opt_first, "first=%d"}, + { Opt_nodir, "nodir=%d"}, + { Opt_err, NULL }, +}; + +const struct lm_lockops gfs2_dlm_ops = { + .lm_proto_name = "lock_dlm", + .lm_mount = gdlm_mount, + .lm_unmount = gdlm_unmount, + .lm_put_lock = gdlm_put_lock, + .lm_lock = gdlm_lock, + .lm_cancel = gdlm_cancel, + .lm_tokens = &dlm_tokens, +}; + |