diff options
Diffstat (limited to 'usr/src/uts/common/fs/hyprlofs/hyprlofs_vfsops.c')
| -rw-r--r-- | usr/src/uts/common/fs/hyprlofs/hyprlofs_vfsops.c | 613 |
1 files changed, 613 insertions, 0 deletions
diff --git a/usr/src/uts/common/fs/hyprlofs/hyprlofs_vfsops.c b/usr/src/uts/common/fs/hyprlofs/hyprlofs_vfsops.c new file mode 100644 index 0000000000..bf80da6dbe --- /dev/null +++ b/usr/src/uts/common/fs/hyprlofs/hyprlofs_vfsops.c @@ -0,0 +1,613 @@ +/* + * CDDL HEADER START + * + * The contents of this file are subject to the terms of the + * Common Development and Distribution License (the "License"). + * You may not use this file except in compliance with the License. + * + * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE + * or http://www.opensolaris.org/os/licensing. + * See the License for the specific language governing permissions + * and limitations under the License. + * + * When distributing Covered Code, include this CDDL HEADER in each + * file and include the License file at usr/src/OPENSOLARIS.LICENSE. + * If applicable, add the following below this CDDL HEADER, with the + * fields enclosed by brackets "[]" replaced with your own identifying + * information: Portions Copyright [yyyy] [name of copyright owner] + * + * CDDL HEADER END + */ +/* + * Copyright (c) 2012, Joyent, Inc. All rights reserved. + */ + +/* + * Hyperlofs is a hybrid file system combining features of the tmpfs(7FS) and + * lofs(7FS) file systems. It is modeled on code from both of these file + * systems. + * + * The purpose is to create a high performance name space for files on which + * applications will compute. Given a large number of data files with various + * owners, we want to construct a view onto those files such that only a subset + * is visible to the applications and such that the view can be changed very + * quickly as compute progresses. Entries in the name space are not mounts and + * thus do not appear in the mnttab. Entries in the name space are allowed to + * refer to files on different backing file systems. Intermediate directories + * in the name space exist only in-memory, ala tmpfs. There are no leaf nodes + * in the name space except for entries that refer to backing files ala lofs. + * + * The name space is managed via ioctls issued on the mounted file system and + * is mostly read-only for the compute applications. That is, applications + * cannot create new files in the name space. If a file is unlinked by an + * application, that only removes the file from the name space, the backing + * file remains in place. It is possible for applications to write-through to + * the backing files if the file system is mounted read-write. + * + * The name space is managed via the HYPRLOFS_ADD_ENTRIES, HYPRLOFS_RM_ENTRIES, + * and HYPRLOFS_RM_ALL ioctls on the top-level mount. + * + * The HYPRLOFS_ADD_ENTRIES ioctl specifies path(s) to the backing file(s) and + * the name(s) for the file(s) in the name space. The name(s) may be path(s) + * which will be relative to the root of the mount and thus cannot begin with + * a /. If the name is a path, it does not have to correspond to any backing + * path. The intermediate directories will only exist in the name space. The + * entry(ies) will be added to the name space. + * + * The HYPRLOFS_RM_ENTRIES ioctl specifies the name(s) of the file(s) in the + * name space which should be removed. The name(s) may be path(s) which will + * be relative to the root of the mount and thus cannot begin with a /. The + * named entry(ies) will be removed. + * + * The HYPRLOFS_RM_ALL ioctl will remove all mappings from the name space. + */ + +#include <sys/types.h> +#include <sys/param.h> +#include <sys/sysmacros.h> +#include <sys/kmem.h> +#include <sys/time.h> +#include <sys/pathname.h> +#include <sys/vfs.h> +#include <sys/vfs_opreg.h> +#include <sys/vnode.h> +#include <sys/stat.h> +#include <sys/uio.h> +#include <sys/stat.h> +#include <sys/errno.h> +#include <sys/cmn_err.h> +#include <sys/cred.h> +#include <sys/statvfs.h> +#include <sys/mount.h> +#include <sys/debug.h> +#include <sys/systm.h> +#include <sys/mntent.h> +#include <fs/fs_subr.h> +#include <vm/page.h> +#include <vm/anon.h> +#include <sys/model.h> +#include <sys/policy.h> + +#include <sys/fs/swapnode.h> +#include <sys/fs/hyprlofs_info.h> + +static int hyprlofsfstype; + +/* + * hyprlofs vfs operations. + */ +static int hyprlofsinit(int, char *); +static int hyprlofs_mount(vfs_t *, vnode_t *, struct mounta *, cred_t *); +static int hyprlofs_unmount(vfs_t *, int, cred_t *); +static int hyprlofs_root(vfs_t *, vnode_t **); +static int hyprlofs_statvfs(vfs_t *, struct statvfs64 *); +static int hyprlofs_vget(vfs_t *, vnode_t **, struct fid *); + +/* + * Loadable module wrapper + */ +#include <sys/modctl.h> + +static mntopts_t hyprlofs_mntopts; + +static vfsdef_t vfw = { + VFSDEF_VERSION, + "hyprlofs", + hyprlofsinit, + VSW_HASPROTO|VSW_CANREMOUNT|VSW_STATS|VSW_ZMOUNT, + &hyprlofs_mntopts +}; + +static mntopts_t hyprlofs_mntopts = { + 0, NULL +}; + +/* + * Module linkage information + */ +static struct modlfs modlfs = { + &mod_fsops, "filesystem for hyprlofs", &vfw +}; + +static struct modlinkage modlinkage = { + MODREV_1, &modlfs, NULL +}; + +int +_init() +{ + return (mod_install(&modlinkage)); +} + +int +_fini() +{ + int error; + + error = mod_remove(&modlinkage); + if (error) + return (error); + /* + * Tear down the operations vectors + */ + (void) vfs_freevfsops_by_type(hyprlofsfstype); + vn_freevnodeops(hyprlofs_vnodeops); + return (0); +} + +int +_info(struct modinfo *modinfop) +{ + return (mod_info(&modlinkage, modinfop)); +} + +/* + * The following are patchable variables limiting the amount of system + * resources hyprlofs can use. + * + * hyprlofs_maxkmem limits the amount of kernel kmem_alloc memory hyprlofs can + * use for it's data structures (e.g. hlnodes, directory entries). It is set + * as a percentage of physical memory which is determined when hyprlofs is + * first used in the system. + * + * hyprlofs_minfree is the minimum amount of swap space that hyprlofs leaves for + * the rest of the system. If the amount of free swap space in the system + * (i.e. anoninfo.ani_free) drops below hyprlofs_minfree, hyprlofs anon + * allocations will fail. + */ +size_t hyprlofs_maxkmem = 0; +size_t hyprlofs_minfree = 0; +size_t hyprlofs_kmemspace; /* bytes of kernel heap used by all hyprlofs */ + +static major_t hyprlofs_major; +static minor_t hyprlofs_minor; +static kmutex_t hyprlofs_minor_lock; + +/* + * initialize global hyprlofs locks and hashes when loading hyprlofs module + */ +static int +hyprlofsinit(int fstype, char *name) +{ + static const fs_operation_def_t hl_vfsops_template[] = { + VFSNAME_MOUNT, { .vfs_mount = hyprlofs_mount }, + VFSNAME_UNMOUNT, { .vfs_unmount = hyprlofs_unmount }, + VFSNAME_ROOT, { .vfs_root = hyprlofs_root }, + VFSNAME_STATVFS, { .vfs_statvfs = hyprlofs_statvfs }, + VFSNAME_VGET, { .vfs_vget = hyprlofs_vget }, + NULL, NULL + }; + int error; + extern void hyprlofs_hash_init(); + + hyprlofs_hash_init(); + hyprlofsfstype = fstype; + ASSERT(hyprlofsfstype != 0); + + error = vfs_setfsops(fstype, hl_vfsops_template, NULL); + if (error != 0) { + cmn_err(CE_WARN, "hyprlofsinit: bad vfs ops template"); + return (error); + } + + error = vn_make_ops(name, hyprlofs_vnodeops_template, + &hyprlofs_vnodeops); + if (error != 0) { + (void) vfs_freevfsops_by_type(fstype); + cmn_err(CE_WARN, "hyprlofsinit: bad vnode ops template"); + return (error); + } + + /* + * hyprlofs_minfree is an absolute limit of swap space which still + * allows other processes to execute. Set it if its not patched. + */ + if (hyprlofs_minfree == 0) + hyprlofs_minfree = btopr(HYPRLOFSMINFREE); + + if ((hyprlofs_major = getudev()) == (major_t)-1) { + cmn_err(CE_WARN, + "hyprlofsinit: Can't get unique device number."); + hyprlofs_major = 0; + } + mutex_init(&hyprlofs_minor_lock, NULL, MUTEX_DEFAULT, NULL); + return (0); +} + +static int +hyprlofs_mount(vfs_t *vfsp, vnode_t *mvp, struct mounta *uap, cred_t *cr) +{ + hlfsmount_t *hm = NULL; + hlnode_t *hp; + struct pathname dpn; + int error; + vattr_t rattr; + int got_attrs; + + if ((error = secpolicy_fs_mount(cr, mvp, vfsp)) != 0) + return (error); + if (secpolicy_hyprlofs_control(cr) != 0) + return (EPERM); + + if (mvp->v_type != VDIR) + return (ENOTDIR); + + if (uap->flags & MS_REMOUNT) + return (EBUSY); + + mutex_enter(&mvp->v_lock); + if ((uap->flags & MS_OVERLAY) == 0 && + (mvp->v_count != 1 || (mvp->v_flag & VROOT))) { + mutex_exit(&mvp->v_lock); + return (EBUSY); + } + mutex_exit(&mvp->v_lock); + + /* Having the resource be anything but "swap" doesn't make sense. */ + vfs_setresource(vfsp, "swap", 0); + + if ((error = pn_get(uap->dir, + (uap->flags & MS_SYSSPACE) ? UIO_SYSSPACE : UIO_USERSPACE, + &dpn)) != 0) + goto out; + + if ((hm = kmem_zalloc(sizeof (hlfsmount_t), KM_NOSLEEP_LAZY)) == NULL) { + pn_free(&dpn); + error = ENOMEM; + goto out; + } + + /* Get an available minor device number for this mount */ + mutex_enter(&hyprlofs_minor_lock); + do { + hyprlofs_minor = (hyprlofs_minor + 1) & L_MAXMIN32; + hm->hlm_dev = makedevice(hyprlofs_major, hyprlofs_minor); + } while (vfs_devismounted(hm->hlm_dev)); + mutex_exit(&hyprlofs_minor_lock); + + /* + * Set but don't bother entering the mutex since hlfsmount is not on + * the mount list yet. + */ + mutex_init(&hm->hlm_contents, NULL, MUTEX_DEFAULT, NULL); + + hm->hlm_vfsp = vfsp; + + vfsp->vfs_data = (caddr_t)hm; + vfsp->vfs_fstype = hyprlofsfstype; + vfsp->vfs_dev = hm->hlm_dev; + vfsp->vfs_bsize = PAGESIZE; + vfsp->vfs_flag |= VFS_NOTRUNC; + vfs_make_fsid(&vfsp->vfs_fsid, hm->hlm_dev, hyprlofsfstype); + hm->hlm_mntpath = kmem_zalloc(dpn.pn_pathlen + 1, KM_SLEEP); + (void) strcpy(hm->hlm_mntpath, dpn.pn_path); + + /* allocate and initialize root hlnode structure */ + bzero(&rattr, sizeof (vattr_t)); + rattr.va_mode = (mode_t)(S_IFDIR | 0777); + rattr.va_type = VDIR; + rattr.va_rdev = 0; + hp = kmem_zalloc(sizeof (hlnode_t), KM_SLEEP); + hyprlofs_node_init(hm, hp, &rattr, cr); + + /* Get the mode, uid, and gid from the underlying mount point. */ + rattr.va_mask = AT_MODE|AT_UID|AT_GID; + got_attrs = VOP_GETATTR(mvp, &rattr, 0, cr, NULL); + + rw_enter(&hp->hln_rwlock, RW_WRITER); + HLNTOV(hp)->v_flag |= VROOT; + + /* + * If the getattr succeeded, use its results, otherwise allow the + * previously set defaults to prevail. + */ + if (got_attrs == 0) { + hp->hln_mode = rattr.va_mode; + hp->hln_uid = rattr.va_uid; + hp->hln_gid = rattr.va_gid; + } + + /* + * Initialize linked list of hlnodes so that the back pointer of the + * root hlnode always points to the last one on the list and the + * forward pointer of the last node is null + */ + hp->hln_back = hp; + hp->hln_forw = NULL; + hp->hln_nlink = 0; + hm->hlm_rootnode = hp; + + hyprlofs_dirinit(hp, hp); + + rw_exit(&hp->hln_rwlock); + + pn_free(&dpn); + error = 0; + +out: + return (error); +} + +static int +hyprlofs_unmount(vfs_t *vfsp, int flag, cred_t *cr) +{ + hlfsmount_t *hm = (hlfsmount_t *)VFSTOHLM(vfsp); + hlnode_t *hnp, *cancel; + vnode_t *vp; + int error; + + if ((error = secpolicy_fs_unmount(cr, vfsp)) != 0) + return (error); + if (secpolicy_hyprlofs_control(cr) != 0) + return (EPERM); + + /* + * forced unmount is not supported by this file system + * and thus, ENOTSUP, is being returned. + */ + if (flag & MS_FORCE) + return (ENOTSUP); + + mutex_enter(&hm->hlm_contents); + + /* + * If there are no open files, only the root node should have a ref cnt. + * With hlm_contents held, nothing can be added or removed. There may + * be some dirty pages. To prevent fsflush from disrupting the unmount, + * put a hold on each node while scanning. If we find a previously + * referenced node, undo the holds we have placed and fail EBUSY. + */ + hnp = hm->hlm_rootnode; + if (HLNTOV(hnp)->v_count > 1) { + mutex_exit(&hm->hlm_contents); + return (EBUSY); + } + + for (hnp = hnp->hln_forw; hnp; hnp = hnp->hln_forw) { + if ((vp = HLNTOV(hnp))->v_count > 0) { + cancel = hm->hlm_rootnode->hln_forw; + while (cancel != hnp) { + vp = HLNTOV(cancel); + ASSERT(vp->v_count > 0); + VN_RELE(vp); + cancel = cancel->hln_forw; + } + mutex_exit(&hm->hlm_contents); + return (EBUSY); + } + VN_HOLD(vp); + } + + /* We can drop the mutex now because no one can find this mount */ + mutex_exit(&hm->hlm_contents); + + /* + * Free all alloc'd memory associated with this FS. To do this, we go + * through the file list twice, once to remove all the dir entries, and + * then to remove all the files. + */ + + /* Remove all directory entries */ + for (hnp = hm->hlm_rootnode; hnp; hnp = hnp->hln_forw) { + rw_enter(&hnp->hln_rwlock, RW_WRITER); + if (hnp->hln_type == VDIR) + hyprlofs_dirtrunc(hnp); + rw_exit(&hnp->hln_rwlock); + } + + ASSERT(hm->hlm_rootnode); + + /* + * All links are gone, v_count is keeping nodes in place. VN_RELE + * should make the node disappear, unless somebody is holding pages + * against it. Wait and retry until it disappears. + * + * We re-acquire the lock to prevent others who have a HOLD on a hlnode + * from blowing it away (in hyprlofs_inactive) while we're trying to + * get to it here. Once we have a HOLD on it we know it'll stick around. + */ + mutex_enter(&hm->hlm_contents); + + /* Remove all the files (except the rootnode) backwards. */ + while ((hnp = hm->hlm_rootnode->hln_back) != hm->hlm_rootnode) { + mutex_exit(&hm->hlm_contents); + /* Note we handled the link count in pass 2 above. */ + vp = HLNTOV(hnp); + VN_RELE(vp); + mutex_enter(&hm->hlm_contents); + /* + * It's still there after the RELE. Someone else like pageout + * has a hold on it so wait a bit and then try again. + */ + if (hnp == hm->hlm_rootnode->hln_back) { + VN_HOLD(vp); + mutex_exit(&hm->hlm_contents); + delay(hz / 4); + mutex_enter(&hm->hlm_contents); + } + } + mutex_exit(&hm->hlm_contents); + + VN_RELE(HLNTOV(hm->hlm_rootnode)); + + ASSERT(hm->hlm_mntpath); + + kmem_free(hm->hlm_mntpath, strlen(hm->hlm_mntpath) + 1); + + mutex_destroy(&hm->hlm_contents); + kmem_free(hm, sizeof (hlfsmount_t)); + + return (0); +} + +/* Return root hlnode for given vnode */ +static int +hyprlofs_root(vfs_t *vfsp, vnode_t **vpp) +{ + hlfsmount_t *hm = (hlfsmount_t *)VFSTOHLM(vfsp); + hlnode_t *hp = hm->hlm_rootnode; + vnode_t *vp; + + ASSERT(hp); + + vp = HLNTOV(hp); + VN_HOLD(vp); + *vpp = vp; + return (0); +} + +static int +hyprlofs_statvfs(vfs_t *vfsp, struct statvfs64 *sbp) +{ + hlfsmount_t *hm = (hlfsmount_t *)VFSTOHLM(vfsp); + ulong_t blocks; + dev32_t d32; + zoneid_t eff_zid; + struct zone *zp; + + /* + * The FS may have been mounted by the GZ on behalf of the NGZ. In + * that case, the hlfsmount zone_id will be the global zone. We want + * to show the swap cap inside the zone in this case, even though the + * FS was mounted by the GZ. + */ + if (curproc->p_zone->zone_id != GLOBAL_ZONEUNIQID) + zp = curproc->p_zone; + else + zp = hm->hlm_vfsp->vfs_zone; + + if (zp == NULL) + eff_zid = GLOBAL_ZONEUNIQID; + else + eff_zid = zp->zone_id; + + sbp->f_bsize = PAGESIZE; + sbp->f_frsize = PAGESIZE; + + /* + * Find the amount of available physical and memory swap + */ + mutex_enter(&anoninfo_lock); + ASSERT(k_anoninfo.ani_max >= k_anoninfo.ani_phys_resv); + blocks = (ulong_t)CURRENT_TOTAL_AVAILABLE_SWAP; + mutex_exit(&anoninfo_lock); + + if (blocks > hyprlofs_minfree) + sbp->f_bfree = blocks - hyprlofs_minfree; + else + sbp->f_bfree = 0; + + sbp->f_bavail = sbp->f_bfree; + + /* + * Total number of blocks is what's available plus what's been used + */ + sbp->f_blocks = (fsblkcnt64_t)(sbp->f_bfree); + + if (eff_zid != GLOBAL_ZONEUNIQID && + zp->zone_max_swap_ctl != UINT64_MAX) { + /* + * If the fs is used by a NGZ with a swap cap, then report the + * capped size. + */ + rctl_qty_t cap, used; + pgcnt_t pgcap, pgused; + + mutex_enter(&zp->zone_mem_lock); + cap = zp->zone_max_swap_ctl; + used = zp->zone_max_swap; + mutex_exit(&zp->zone_mem_lock); + + pgcap = btop(cap); + pgused = btop(used); + + sbp->f_bfree = MIN(pgcap - pgused, sbp->f_bfree); + sbp->f_bavail = sbp->f_bfree; + sbp->f_blocks = MIN(pgcap, sbp->f_blocks); + } + + /* + * This is fairly inaccurate since it doesn't take into account the + * names stored in the directory entries. + */ + sbp->f_ffree = sbp->f_files = ptob(availrmem) / + (sizeof (hlnode_t) + sizeof (hldirent_t)); + + sbp->f_favail = (fsfilcnt64_t)(sbp->f_ffree); + (void) cmpldev(&d32, vfsp->vfs_dev); + sbp->f_fsid = d32; + (void) strcpy(sbp->f_basetype, vfssw[hyprlofsfstype].vsw_name); + (void) strncpy(sbp->f_fstr, hm->hlm_mntpath, sizeof (sbp->f_fstr)); + /* + * ensure null termination + */ + sbp->f_fstr[sizeof (sbp->f_fstr) - 1] = '\0'; + sbp->f_flag = vf_to_stf(vfsp->vfs_flag); + sbp->f_namemax = MAXNAMELEN - 1; + return (0); +} + +static int +hyprlofs_vget(vfs_t *vfsp, vnode_t **vpp, struct fid *fidp) +{ + hlfid_t *hfid; + hlfsmount_t *hm = (hlfsmount_t *)VFSTOHLM(vfsp); + hlnode_t *hp = NULL; + + hfid = (hlfid_t *)fidp; + *vpp = NULL; + + mutex_enter(&hm->hlm_contents); + for (hp = hm->hlm_rootnode; hp; hp = hp->hln_forw) { + mutex_enter(&hp->hln_tlock); + if (hp->hln_nodeid == hfid->hlfid_ino) { + /* + * If the gen numbers don't match we know the file + * won't be found since only one hlnode can have this + * number at a time. + */ + if (hp->hln_gen != hfid->hlfid_gen || + hp->hln_nlink == 0) { + mutex_exit(&hp->hln_tlock); + mutex_exit(&hm->hlm_contents); + return (0); + } + *vpp = (vnode_t *)HLNTOV(hp); + + VN_HOLD(*vpp); + + if ((hp->hln_mode & S_ISVTX) && + !(hp->hln_mode & (S_IXUSR | S_IFDIR))) { + mutex_enter(&(*vpp)->v_lock); + (*vpp)->v_flag |= VISSWAP; + mutex_exit(&(*vpp)->v_lock); + } + mutex_exit(&hp->hln_tlock); + mutex_exit(&hm->hlm_contents); + return (0); + } + mutex_exit(&hp->hln_tlock); + } + mutex_exit(&hm->hlm_contents); + return (0); +} |