int ufs_balloc_range(struct vnode *vp, off_t off, off_t len, kauth_cred_t cred, int flags) { off_t neweof; /* file size after the operation */ off_t neweob; /* offset next to the last block after the operation */ off_t pagestart; /* starting offset of range covered by pgs */ off_t eob; /* offset next to allocated blocks */ struct uvm_object *uobj; int i, delta, error, npages; int bshift = vp->v_mount->mnt_fs_bshift; int bsize = 1 << bshift; int ppb = MAX(bsize >> PAGE_SHIFT, 1); struct vm_page **pgs; size_t pgssize; UVMHIST_FUNC("ufs_balloc_range"); UVMHIST_CALLED(ubchist); UVMHIST_LOG(ubchist, "vp %p off 0x%x len 0x%x u_size 0x%x", vp, off, len, vp->v_size); neweof = MAX(vp->v_size, off + len); GOP_SIZE(vp, neweof, &neweob, 0); error = 0; uobj = &vp->v_uobj; /* * read or create pages covering the range of the allocation and * keep them locked until the new block is allocated, so there * will be no window where the old contents of the new block are * visible to racing threads. */ pagestart = trunc_page(off) & ~(bsize - 1); npages = MIN(ppb, (round_page(neweob) - pagestart) >> PAGE_SHIFT); pgssize = npages * sizeof(struct vm_page *); pgs = kmem_zalloc(pgssize, KM_SLEEP); mutex_enter(&uobj->vmobjlock); error = VOP_GETPAGES(vp, pagestart, pgs, &npages, 0, VM_PROT_WRITE, 0, PGO_SYNCIO|PGO_PASTEOF|PGO_NOBLOCKALLOC|PGO_NOTIMESTAMP); if (error) { goto out; } mutex_enter(&uobj->vmobjlock); mutex_enter(&uvm_pageqlock); for (i = 0; i < npages; i++) { UVMHIST_LOG(ubchist, "got pgs[%d] %p", i, pgs[i],0,0); KASSERT((pgs[i]->flags & PG_RELEASED) == 0); pgs[i]->flags &= ~PG_CLEAN; uvm_pageactivate(pgs[i]); } mutex_exit(&uvm_pageqlock); mutex_exit(&uobj->vmobjlock); /* * adjust off to be block-aligned. */ delta = off & (bsize - 1); off -= delta; len += delta; /* * now allocate the range. */ genfs_node_wrlock(vp); error = GOP_ALLOC(vp, off, len, flags, cred); genfs_node_unlock(vp); /* * clear PG_RDONLY on any pages we are holding * (since they now have backing store) and unbusy them. */ GOP_SIZE(vp, off + len, &eob, 0); mutex_enter(&uobj->vmobjlock); for (i = 0; i < npages; i++) { if (error) { pgs[i]->flags |= PG_RELEASED; } else if (off <= pagestart + (i << PAGE_SHIFT) && pagestart + ((i + 1) << PAGE_SHIFT) <= eob) { pgs[i]->flags &= ~PG_RDONLY; } } if (error) { mutex_enter(&uvm_pageqlock); uvm_page_unbusy(pgs, npages); mutex_exit(&uvm_pageqlock); } else { uvm_page_unbusy(pgs, npages); } mutex_exit(&uobj->vmobjlock); out: kmem_free(pgs, pgssize); return error; }
/* * miscfs/genfs getpages routine. This is a fair bit simpler than the * kernel counterpart since we're not being executed from a fault handler * and generally don't need to care about PGO_LOCKED or other cruft. * We do, however, need to care about page locking and we keep trying until * we get all the pages within the range. The object locking protocol * is the same as for the kernel: enter with the object lock held, * return with it released. */ int genfs_getpages(void *v) { struct vop_getpages_args /* { struct vnode *a_vp; voff_t a_offset; struct vm_page **a_m; int *a_count; int a_centeridx; vm_prot_t a_access_type; int a_advice; int a_flags; } */ *ap = v; struct vnode *vp = ap->a_vp; struct uvm_object *uobj = (struct uvm_object *)vp; struct vm_page *pg; voff_t curoff, endoff; off_t diskeof; size_t bufsize, remain, bufoff, xfersize; uint8_t *tmpbuf; int bshift = vp->v_mount->mnt_fs_bshift; int bsize = 1<<bshift; int count = *ap->a_count; int async; int i, error; /* * Ignore async for now, the structure of this routine * doesn't exactly allow for it ... */ async = 0; if (ap->a_centeridx != 0) panic("%s: centeridx != not supported", __func__); if (ap->a_access_type & VM_PROT_WRITE) vp->v_iflag |= VI_ONWORKLST; curoff = ap->a_offset & ~PAGE_MASK; for (i = 0; i < count; i++, curoff += PAGE_SIZE) { retrylookup: pg = uvm_pagelookup(uobj, curoff); if (pg == NULL) break; /* page is busy? we need to wait until it's released */ if (pg->flags & PG_BUSY) { pg->flags |= PG_WANTED; UVM_UNLOCK_AND_WAIT(pg, &uobj->vmobjlock, 0, "getpg",0); mutex_enter(&uobj->vmobjlock); goto retrylookup; } pg->flags |= PG_BUSY; if (pg->flags & PG_FAKE) break; ap->a_m[i] = pg; } /* got everything? if so, just return */ if (i == count) { mutex_exit(&uobj->vmobjlock); return 0; } /* * didn't? Ok, allocate backing pages. Start from the first * one we missed. */ for (; i < count; i++, curoff += PAGE_SIZE) { retrylookup2: pg = uvm_pagelookup(uobj, curoff); /* found? busy it and be happy */ if (pg) { if (pg->flags & PG_BUSY) { pg->flags = PG_WANTED; UVM_UNLOCK_AND_WAIT(pg, &uobj->vmobjlock, 0, "getpg2", 0); mutex_enter(&uobj->vmobjlock); goto retrylookup2; } else { pg->flags |= PG_BUSY; } /* not found? make a new page */ } else { pg = rumpvm_makepage(uobj, curoff); } ap->a_m[i] = pg; } /* * We have done all the clerical work and have all pages busied. * Release the vm object for other consumers. */ mutex_exit(&uobj->vmobjlock); /* * Now, we have all the pages here & busy. Transfer the range * starting from the missing offset and transfer into the * page buffers. */ GOP_SIZE(vp, vp->v_size, &diskeof, 0); /* align to boundaries */ endoff = trunc_page(ap->a_offset) + (count << PAGE_SHIFT); endoff = MIN(endoff, ((vp->v_writesize+bsize-1) & ~(bsize-1))); curoff = ap->a_offset & ~(MAX(bsize,PAGE_SIZE)-1); remain = endoff - curoff; if (diskeof > curoff) remain = MIN(remain, diskeof - curoff); DPRINTF(("a_offset: %llx, startoff: 0x%llx, endoff 0x%llx\n", (unsigned long long)ap->a_offset, (unsigned long long)curoff, (unsigned long long)endoff)); /* read everything into a buffer */ bufsize = round_page(remain); tmpbuf = kmem_zalloc(bufsize, KM_SLEEP); for (bufoff = 0; remain; remain -= xfersize, bufoff+=xfersize) { struct buf *bp; struct vnode *devvp; daddr_t lbn, bn; int run; lbn = (curoff + bufoff) >> bshift; /* XXX: assume eof */ error = VOP_BMAP(vp, lbn, &devvp, &bn, &run); if (error) panic("%s: VOP_BMAP & lazy bum: %d", __func__, error); DPRINTF(("lbn %d (off %d) -> bn %d run %d\n", (int)lbn, (int)(curoff+bufoff), (int)bn, run)); xfersize = MIN(((lbn+1+run)<<bshift)-(curoff+bufoff), remain); /* hole? */ if (bn == -1) { memset(tmpbuf + bufoff, 0, xfersize); continue; } bp = getiobuf(vp, true); bp->b_data = tmpbuf + bufoff; bp->b_bcount = xfersize; bp->b_blkno = bn; bp->b_lblkno = 0; bp->b_flags = B_READ; bp->b_cflags = BC_BUSY; if (async) { bp->b_flags |= B_ASYNC; bp->b_iodone = uvm_aio_biodone; } VOP_STRATEGY(devvp, bp); if (bp->b_error) panic("%s: VOP_STRATEGY, lazy bum", __func__); if (!async) putiobuf(bp); } /* skip to beginning of pages we're interested in */ bufoff = 0; while (round_page(curoff + bufoff) < trunc_page(ap->a_offset)) bufoff += PAGE_SIZE; DPRINTF(("first page offset 0x%x\n", (int)(curoff + bufoff))); for (i = 0; i < count; i++, bufoff += PAGE_SIZE) { /* past our prime? */ if (curoff + bufoff >= endoff) break; pg = uvm_pagelookup(&vp->v_uobj, curoff + bufoff); KASSERT(pg); DPRINTF(("got page %p (off 0x%x)\n", pg, (int)(curoff+bufoff))); if (pg->flags & PG_FAKE) { memcpy((void *)pg->uanon, tmpbuf+bufoff, PAGE_SIZE); pg->flags &= ~PG_FAKE; pg->flags |= PG_CLEAN; } ap->a_m[i] = pg; } *ap->a_count = i; kmem_free(tmpbuf, bufsize); return 0; }
/* * Write a directory entry after a call to namei, using the parameters * that ulfs_lookup left in nameidata and in the ulfs_lookup_results. * * DVP is the directory to be updated. It must be locked. * ULR is the ulfs_lookup_results structure from the final lookup step. * TVP is not used. (XXX: why is it here? remove it) * DIRP is the new directory entry contents. * CNP is the componentname from the final lookup step. * NEWDIRBP is not used and (XXX) should be removed. The previous * comment here said it was used by the now-removed softupdates code. * * The link count of the target inode is *not* incremented; the * caller does that. * * If ulr->ulr_count is 0, ulfs_lookup did not find space to insert the * directory entry. ulr_offset, which is the place to put the entry, * should be on a block boundary (and should be at the end of the * directory AFAIK) and a fresh block is allocated to put the new * directory entry in. * * If ulr->ulr_count is not zero, ulfs_lookup found a slot to insert * the entry into. This slot ranges from ulr_offset to ulr_offset + * ulr_count. However, this slot may already be partially populated * requiring compaction. See notes below. * * Furthermore, if ulr_count is not zero and ulr_endoff is not the * same as i_size, the directory is truncated to size ulr_endoff. */ int ulfs_direnter(struct vnode *dvp, const struct ulfs_lookup_results *ulr, struct vnode *tvp, struct lfs_direct *dirp, struct componentname *cnp, struct buf *newdirbp) { kauth_cred_t cr; int newentrysize; struct inode *dp; struct buf *bp; u_int dsize; struct lfs_direct *ep, *nep; int error, ret, lfs_blkoff, loc, spacefree; char *dirbuf; struct timespec ts; struct ulfsmount *ump = VFSTOULFS(dvp->v_mount); struct lfs *fs = ump->um_lfs; const int needswap = ULFS_MPNEEDSWAP(fs); int dirblksiz = fs->um_dirblksiz; error = 0; cr = cnp->cn_cred; dp = VTOI(dvp); newentrysize = LFS_DIRSIZ(0, dirp, 0); if (ulr->ulr_count == 0) { /* * If ulr_count is 0, then namei could find no * space in the directory. Here, ulr_offset will * be on a directory block boundary and we will write the * new entry into a fresh block. */ if (ulr->ulr_offset & (dirblksiz - 1)) panic("ulfs_direnter: newblk"); if ((error = lfs_balloc(dvp, (off_t)ulr->ulr_offset, dirblksiz, cr, B_CLRBUF | B_SYNC, &bp)) != 0) { return (error); } dp->i_size = ulr->ulr_offset + dirblksiz; DIP_ASSIGN(dp, size, dp->i_size); dp->i_flag |= IN_CHANGE | IN_UPDATE; uvm_vnp_setsize(dvp, dp->i_size); dirp->d_reclen = ulfs_rw16(dirblksiz, needswap); dirp->d_ino = ulfs_rw32(dirp->d_ino, needswap); if (FSFMT(dvp)) { #if (BYTE_ORDER == LITTLE_ENDIAN) if (needswap == 0) { #else if (needswap != 0) { #endif u_char tmp = dirp->d_namlen; dirp->d_namlen = dirp->d_type; dirp->d_type = tmp; } } lfs_blkoff = ulr->ulr_offset & (ump->um_mountp->mnt_stat.f_iosize - 1); memcpy((char *)bp->b_data + lfs_blkoff, dirp, newentrysize); #ifdef LFS_DIRHASH if (dp->i_dirhash != NULL) { ulfsdirhash_newblk(dp, ulr->ulr_offset); ulfsdirhash_add(dp, dirp, ulr->ulr_offset); ulfsdirhash_checkblock(dp, (char *)bp->b_data + lfs_blkoff, ulr->ulr_offset); } #endif error = VOP_BWRITE(bp->b_vp, bp); vfs_timestamp(&ts); ret = lfs_update(dvp, &ts, &ts, UPDATE_DIROP); if (error == 0) return (ret); return (error); } /* * If ulr_count is non-zero, then namei found space for the new * entry in the range ulr_offset to ulr_offset + ulr_count * in the directory. To use this space, we may have to compact * the entries located there, by copying them together towards the * beginning of the block, leaving the free space in one usable * chunk at the end. */ /* * Increase size of directory if entry eats into new space. * This should never push the size past a new multiple of * DIRBLKSIZ. * * N.B. - THIS IS AN ARTIFACT OF 4.2 AND SHOULD NEVER HAPPEN. */ if (ulr->ulr_offset + ulr->ulr_count > dp->i_size) { #ifdef DIAGNOSTIC printf("ulfs_direnter: reached 4.2-only block, " "not supposed to happen\n"); #endif dp->i_size = ulr->ulr_offset + ulr->ulr_count; DIP_ASSIGN(dp, size, dp->i_size); dp->i_flag |= IN_CHANGE | IN_UPDATE; } /* * Get the block containing the space for the new directory entry. */ error = ulfs_blkatoff(dvp, (off_t)ulr->ulr_offset, &dirbuf, &bp, true); if (error) { return (error); } /* * Find space for the new entry. In the simple case, the entry at * offset base will have the space. If it does not, then namei * arranged that compacting the region ulr_offset to * ulr_offset + ulr_count would yield the space. */ ep = (struct lfs_direct *)dirbuf; dsize = (ep->d_ino != 0) ? LFS_DIRSIZ(FSFMT(dvp), ep, needswap) : 0; spacefree = ulfs_rw16(ep->d_reclen, needswap) - dsize; for (loc = ulfs_rw16(ep->d_reclen, needswap); loc < ulr->ulr_count; ) { uint16_t reclen; nep = (struct lfs_direct *)(dirbuf + loc); /* Trim the existing slot (NB: dsize may be zero). */ ep->d_reclen = ulfs_rw16(dsize, needswap); ep = (struct lfs_direct *)((char *)ep + dsize); reclen = ulfs_rw16(nep->d_reclen, needswap); loc += reclen; if (nep->d_ino == 0) { /* * A mid-block unused entry. Such entries are * never created by the kernel, but fsck_ffs * can create them (and it doesn't fix them). * * Add up the free space, and initialise the * relocated entry since we don't memcpy it. */ spacefree += reclen; ep->d_ino = 0; dsize = 0; continue; } dsize = LFS_DIRSIZ(FSFMT(dvp), nep, needswap); spacefree += reclen - dsize; #ifdef LFS_DIRHASH if (dp->i_dirhash != NULL) ulfsdirhash_move(dp, nep, ulr->ulr_offset + ((char *)nep - dirbuf), ulr->ulr_offset + ((char *)ep - dirbuf)); #endif memcpy((void *)ep, (void *)nep, dsize); } /* * Here, `ep' points to a directory entry containing `dsize' in-use * bytes followed by `spacefree' unused bytes. If ep->d_ino == 0, * then the entry is completely unused (dsize == 0). The value * of ep->d_reclen is always indeterminate. * * Update the pointer fields in the previous entry (if any), * copy in the new entry, and write out the block. */ if (ep->d_ino == 0 || (ulfs_rw32(ep->d_ino, needswap) == ULFS_WINO && memcmp(ep->d_name, dirp->d_name, dirp->d_namlen) == 0)) { if (spacefree + dsize < newentrysize) panic("ulfs_direnter: compact1"); dirp->d_reclen = spacefree + dsize; } else { if (spacefree < newentrysize) panic("ulfs_direnter: compact2"); dirp->d_reclen = spacefree; ep->d_reclen = ulfs_rw16(dsize, needswap); ep = (struct lfs_direct *)((char *)ep + dsize); } dirp->d_reclen = ulfs_rw16(dirp->d_reclen, needswap); dirp->d_ino = ulfs_rw32(dirp->d_ino, needswap); if (FSFMT(dvp)) { #if (BYTE_ORDER == LITTLE_ENDIAN) if (needswap == 0) { #else if (needswap != 0) { #endif u_char tmp = dirp->d_namlen; dirp->d_namlen = dirp->d_type; dirp->d_type = tmp; } } #ifdef LFS_DIRHASH if (dp->i_dirhash != NULL && (ep->d_ino == 0 || dirp->d_reclen == spacefree)) ulfsdirhash_add(dp, dirp, ulr->ulr_offset + ((char *)ep - dirbuf)); #endif memcpy((void *)ep, (void *)dirp, (u_int)newentrysize); #ifdef LFS_DIRHASH if (dp->i_dirhash != NULL) ulfsdirhash_checkblock(dp, dirbuf - (ulr->ulr_offset & (dirblksiz - 1)), ulr->ulr_offset & ~(dirblksiz - 1)); #endif error = VOP_BWRITE(bp->b_vp, bp); dp->i_flag |= IN_CHANGE | IN_UPDATE; /* * If all went well, and the directory can be shortened, proceed * with the truncation. Note that we have to unlock the inode for * the entry that we just entered, as the truncation may need to * lock other inodes which can lead to deadlock if we also hold a * lock on the newly entered node. */ if (error == 0 && ulr->ulr_endoff && ulr->ulr_endoff < dp->i_size) { #ifdef LFS_DIRHASH if (dp->i_dirhash != NULL) ulfsdirhash_dirtrunc(dp, ulr->ulr_endoff); #endif (void) lfs_truncate(dvp, (off_t)ulr->ulr_endoff, IO_SYNC, cr); } return (error); } /* * Remove a directory entry after a call to namei, using the * parameters that ulfs_lookup left in nameidata and in the * ulfs_lookup_results. * * DVP is the directory to be updated. It must be locked. * ULR is the ulfs_lookup_results structure from the final lookup step. * IP, if not null, is the inode being unlinked. * FLAGS may contain DOWHITEOUT. * ISRMDIR is not used and (XXX) should be removed. * * If FLAGS contains DOWHITEOUT the entry is replaced with a whiteout * instead of being cleared. * * ulr->ulr_offset contains the position of the directory entry * to be removed. * * ulr->ulr_reclen contains the size of the directory entry to be * removed. * * ulr->ulr_count contains the size of the *previous* directory * entry. This allows finding it, for free space management. If * ulr_count is 0, the target entry is at the beginning of the * directory. (Does this ever happen? The first entry should be ".", * which should only be removed at rmdir time. Does rmdir come here * to clear out the "." and ".." entries? Perhaps, but I doubt it.) * * The space is marked free by adding it to the record length (not * name length) of the preceding entry. If the first entry becomes * free, it is marked free by setting the inode number to 0. * * The link count of IP is decremented. Note that this is not the * inverse behavior of ulfs_direnter, which does not adjust link * counts. Sigh. */ int ulfs_dirremove(struct vnode *dvp, const struct ulfs_lookup_results *ulr, struct inode *ip, int flags, int isrmdir) { struct inode *dp = VTOI(dvp); struct lfs_direct *ep; struct buf *bp; int error; const int needswap = ULFS_MPNEEDSWAP(dp->i_lfs); if (flags & DOWHITEOUT) { /* * Whiteout entry: set d_ino to ULFS_WINO. */ error = ulfs_blkatoff(dvp, (off_t)ulr->ulr_offset, (void *)&ep, &bp, true); if (error) return (error); ep->d_ino = ulfs_rw32(ULFS_WINO, needswap); ep->d_type = LFS_DT_WHT; goto out; } if ((error = ulfs_blkatoff(dvp, (off_t)(ulr->ulr_offset - ulr->ulr_count), (void *)&ep, &bp, true)) != 0) return (error); #ifdef LFS_DIRHASH /* * Remove the dirhash entry. This is complicated by the fact * that `ep' is the previous entry when ulr_count != 0. */ if (dp->i_dirhash != NULL) ulfsdirhash_remove(dp, (ulr->ulr_count == 0) ? ep : (struct lfs_direct *)((char *)ep + ulfs_rw16(ep->d_reclen, needswap)), ulr->ulr_offset); #endif if (ulr->ulr_count == 0) { /* * First entry in block: set d_ino to zero. */ ep->d_ino = 0; } else { /* * Collapse new free space into previous entry. */ ep->d_reclen = ulfs_rw16(ulfs_rw16(ep->d_reclen, needswap) + ulr->ulr_reclen, needswap); } #ifdef LFS_DIRHASH if (dp->i_dirhash != NULL) { int dirblksiz = ip->i_lfs->um_dirblksiz; ulfsdirhash_checkblock(dp, (char *)ep - ((ulr->ulr_offset - ulr->ulr_count) & (dirblksiz - 1)), ulr->ulr_offset & ~(dirblksiz - 1)); } #endif out: if (ip) { ip->i_nlink--; DIP_ASSIGN(ip, nlink, ip->i_nlink); ip->i_flag |= IN_CHANGE; } /* * XXX did it ever occur to anyone that it might be a good * idea to restore ip->i_nlink if this fails? Or something? * Currently on error return from this function the state of * ip->i_nlink depends on what happened, and callers * definitely do not take this into account. */ error = VOP_BWRITE(bp->b_vp, bp); dp->i_flag |= IN_CHANGE | IN_UPDATE; /* * If the last named reference to a snapshot goes away, * drop its snapshot reference so that it will be reclaimed * when last open reference goes away. */ if (ip != 0 && (ip->i_flags & SF_SNAPSHOT) != 0 && ip->i_nlink == 0) ulfs_snapgone(ip); return (error); } /* * Rewrite an existing directory entry to point at the inode supplied. * * DP is the directory to update. * OFFSET is the position of the entry in question. It may come * from ulr_offset of a ulfs_lookup_results. * OIP is the old inode the directory previously pointed to. * NEWINUM is the number of the new inode. * NEWTYPE is the new value for the type field of the directory entry. * (This is ignored if the fs doesn't support that.) * ISRMDIR is not used and (XXX) should be removed. * IFLAGS are added to DP's inode flags. * * The link count of OIP is decremented. Note that the link count of * the new inode is *not* incremented. Yay for symmetry. */ int ulfs_dirrewrite(struct inode *dp, off_t offset, struct inode *oip, ino_t newinum, int newtype, int isrmdir, int iflags) { struct buf *bp; struct lfs_direct *ep; struct vnode *vdp = ITOV(dp); int error; error = ulfs_blkatoff(vdp, offset, (void *)&ep, &bp, true); if (error) return (error); ep->d_ino = ulfs_rw32(newinum, ULFS_IPNEEDSWAP(dp)); if (!FSFMT(vdp)) ep->d_type = newtype; oip->i_nlink--; DIP_ASSIGN(oip, nlink, oip->i_nlink); oip->i_flag |= IN_CHANGE; error = VOP_BWRITE(bp->b_vp, bp); dp->i_flag |= iflags; /* * If the last named reference to a snapshot goes away, * drop its snapshot reference so that it will be reclaimed * when last open reference goes away. */ if ((oip->i_flags & SF_SNAPSHOT) != 0 && oip->i_nlink == 0) ulfs_snapgone(oip); return (error); } /* * Check if a directory is empty or not. * Inode supplied must be locked. * * Using a struct lfs_dirtemplate here is not precisely * what we want, but better than using a struct lfs_direct. * * NB: does not handle corrupted directories. */ int ulfs_dirempty(struct inode *ip, ino_t parentino, kauth_cred_t cred) { doff_t off; struct lfs_dirtemplate dbuf; struct lfs_direct *dp = (struct lfs_direct *)&dbuf; int error, namlen; size_t count; const int needswap = ULFS_IPNEEDSWAP(ip); #define MINDIRSIZ (sizeof (struct lfs_dirtemplate) / 2) for (off = 0; off < ip->i_size; off += ulfs_rw16(dp->d_reclen, needswap)) { error = vn_rdwr(UIO_READ, ITOV(ip), (void *)dp, MINDIRSIZ, off, UIO_SYSSPACE, IO_NODELOCKED, cred, &count, NULL); /* * Since we read MINDIRSIZ, residual must * be 0 unless we're at end of file. */ if (error || count != 0) return (0); /* avoid infinite loops */ if (dp->d_reclen == 0) return (0); /* skip empty entries */ if (dp->d_ino == 0 || ulfs_rw32(dp->d_ino, needswap) == ULFS_WINO) continue; /* accept only "." and ".." */ #if (BYTE_ORDER == LITTLE_ENDIAN) if (FSFMT(ITOV(ip)) && needswap == 0) namlen = dp->d_type; else namlen = dp->d_namlen; #else if (FSFMT(ITOV(ip)) && needswap != 0) namlen = dp->d_type; else namlen = dp->d_namlen; #endif if (namlen > 2) return (0); if (dp->d_name[0] != '.') return (0); /* * At this point namlen must be 1 or 2. * 1 implies ".", 2 implies ".." if second * char is also "." */ if (namlen == 1 && ulfs_rw32(dp->d_ino, needswap) == ip->i_number) continue; if (dp->d_name[1] == '.' && ulfs_rw32(dp->d_ino, needswap) == parentino) continue; return (0); } return (1); } #define ULFS_DIRRABLKS 0 int ulfs_dirrablks = ULFS_DIRRABLKS; /* * ulfs_blkatoff: Return buffer with the contents of block "offset" from * the beginning of directory "vp". If "res" is non-NULL, fill it in with * a pointer to the remaining space in the directory. If the caller intends * to modify the buffer returned, "modify" must be true. */ int ulfs_blkatoff(struct vnode *vp, off_t offset, char **res, struct buf **bpp, bool modify) { struct inode *ip __diagused; struct buf *bp; daddr_t lbn; const int dirrablks = ulfs_dirrablks; daddr_t *blks; int *blksizes; int run, error; struct mount *mp = vp->v_mount; const int bshift = mp->mnt_fs_bshift; const int bsize = 1 << bshift; off_t eof; blks = kmem_alloc((1 + dirrablks) * sizeof(daddr_t), KM_SLEEP); blksizes = kmem_alloc((1 + dirrablks) * sizeof(int), KM_SLEEP); ip = VTOI(vp); KASSERT(vp->v_size == ip->i_size); GOP_SIZE(vp, vp->v_size, &eof, 0); lbn = offset >> bshift; for (run = 0; run <= dirrablks;) { const off_t curoff = lbn << bshift; const int size = MIN(eof - curoff, bsize); if (size == 0) { break; } KASSERT(curoff < eof); blks[run] = lbn; blksizes[run] = size; lbn++; run++; if (size != bsize) { break; } } KASSERT(run >= 1); error = breadn(vp, blks[0], blksizes[0], &blks[1], &blksizes[1], run - 1, NOCRED, (modify ? B_MODIFY : 0), &bp); if (error != 0) { *bpp = NULL; goto out; } if (res) { *res = (char *)bp->b_data + (offset & (bsize - 1)); } *bpp = bp; out: kmem_free(blks, (1 + dirrablks) * sizeof(daddr_t)); kmem_free(blksizes, (1 + dirrablks) * sizeof(int)); return error; }
/* * This is a slightly strangely structured routine. It always puts * all the pages for a vnode. It starts by releasing pages which * are clean and simultaneously looks up the smallest offset for a * dirty page beloning to the object. If there is no smallest offset, * all pages have been cleaned. Otherwise, it finds a contiguous range * of dirty pages starting from the smallest offset and writes them out. * After this the scan is restarted. */ int genfs_do_putpages(struct vnode *vp, off_t startoff, off_t endoff, int flags, struct vm_page **busypg) { char databuf[MAXPHYS]; struct uvm_object *uobj = &vp->v_uobj; struct vm_page *pg, *pg_next; voff_t smallest; voff_t curoff, bufoff; off_t eof; size_t xfersize; int bshift = vp->v_mount->mnt_fs_bshift; int bsize = 1 << bshift; #if 0 int async = (flags & PGO_SYNCIO) == 0; #else int async = 0; #endif restart: /* check if all pages are clean */ smallest = -1; for (pg = TAILQ_FIRST(&uobj->memq); pg; pg = pg_next) { pg_next = TAILQ_NEXT(pg, listq.queue); /* * XXX: this is not correct at all. But it's based on * assumptions we can make when accessing the pages * only through the file system and not through the * virtual memory subsystem. Well, at least I hope * so ;) */ KASSERT((pg->flags & PG_BUSY) == 0); /* If we can just dump the page, do so */ if (pg->flags & PG_CLEAN || flags & PGO_FREE) { uvm_pagefree(pg); continue; } if (pg->offset < smallest || smallest == -1) smallest = pg->offset; } /* all done? */ if (TAILQ_EMPTY(&uobj->memq)) { vp->v_iflag &= ~VI_ONWORKLST; mutex_exit(&uobj->vmobjlock); return 0; } /* we need to flush */ GOP_SIZE(vp, vp->v_writesize, &eof, 0); for (curoff = smallest; curoff < eof; curoff += PAGE_SIZE) { void *curva; if (curoff - smallest >= MAXPHYS) break; pg = uvm_pagelookup(uobj, curoff); if (pg == NULL) break; /* XXX: see comment about above KASSERT */ KASSERT((pg->flags & PG_BUSY) == 0); curva = databuf + (curoff-smallest); memcpy(curva, (void *)pg->uanon, PAGE_SIZE); rumpvm_enterva((vaddr_t)curva, pg); pg->flags |= PG_CLEAN; } KASSERT(curoff > smallest); mutex_exit(&uobj->vmobjlock); /* then we write */ for (bufoff = 0; bufoff < MIN(curoff-smallest,eof); bufoff+=xfersize) { struct buf *bp; struct vnode *devvp; daddr_t bn, lbn; int run, error; lbn = (smallest + bufoff) >> bshift; error = VOP_BMAP(vp, lbn, &devvp, &bn, &run); if (error) panic("%s: VOP_BMAP failed: %d", __func__, error); xfersize = MIN(((lbn+1+run) << bshift) - (smallest+bufoff), curoff - (smallest+bufoff)); /* * We might run across blocks which aren't allocated yet. * A reason might be e.g. the write operation being still * in the kernel page cache while truncate has already * enlarged the file. So just ignore those ranges. */ if (bn == -1) continue; bp = getiobuf(vp, true); /* only write max what we are allowed to write */ bp->b_bcount = xfersize; if (smallest + bufoff + xfersize > eof) bp->b_bcount -= (smallest+bufoff+xfersize) - eof; bp->b_bcount = (bp->b_bcount + DEV_BSIZE-1) & ~(DEV_BSIZE-1); KASSERT(bp->b_bcount > 0); KASSERT(smallest >= 0); DPRINTF(("putpages writing from %x to %x (vp size %x)\n", (int)(smallest + bufoff), (int)(smallest + bufoff + bp->b_bcount), (int)eof)); bp->b_bufsize = round_page(bp->b_bcount); bp->b_lblkno = 0; bp->b_blkno = bn + (((smallest+bufoff)&(bsize-1))>>DEV_BSHIFT); bp->b_data = databuf + bufoff; bp->b_flags = B_WRITE; bp->b_cflags |= BC_BUSY; if (async) { bp->b_flags |= B_ASYNC; bp->b_iodone = uvm_aio_biodone; } vp->v_numoutput++; VOP_STRATEGY(devvp, bp); if (bp->b_error) panic("%s: VOP_STRATEGY lazy bum %d", __func__, bp->b_error); if (!async) putiobuf(bp); } rumpvm_flushva(); mutex_enter(&uobj->vmobjlock); goto restart; }
int ulfs_balloc_range(struct vnode *vp, off_t off, off_t len, kauth_cred_t cred, int flags) { off_t neweof; /* file size after the operation */ off_t neweob; /* offset next to the last block after the operation */ off_t pagestart; /* starting offset of range covered by pgs */ off_t eob; /* offset next to allocated blocks */ struct uvm_object *uobj; int i, delta, error, npages; int bshift = vp->v_mount->mnt_fs_bshift; int bsize = 1 << bshift; int ppb = MAX(bsize >> PAGE_SHIFT, 1); struct vm_page **pgs; size_t pgssize; UVMHIST_FUNC("ulfs_balloc_range"); UVMHIST_CALLED(ubchist); UVMHIST_LOG(ubchist, "vp %p off 0x%x len 0x%x u_size 0x%x", vp, off, len, vp->v_size); neweof = MAX(vp->v_size, off + len); GOP_SIZE(vp, neweof, &neweob, 0); error = 0; uobj = &vp->v_uobj; /* * read or create pages covering the range of the allocation and * keep them locked until the new block is allocated, so there * will be no window where the old contents of the new block are * visible to racing threads. */ pagestart = trunc_page(off) & ~(bsize - 1); npages = MIN(ppb, (round_page(neweob) - pagestart) >> PAGE_SHIFT); pgssize = npages * sizeof(struct vm_page *); pgs = kmem_zalloc(pgssize, KM_SLEEP); /* * adjust off to be block-aligned. */ delta = off & (bsize - 1); off -= delta; len += delta; genfs_node_wrlock(vp); mutex_enter(uobj->vmobjlock); error = VOP_GETPAGES(vp, pagestart, pgs, &npages, 0, VM_PROT_WRITE, 0, PGO_SYNCIO | PGO_PASTEOF | PGO_NOBLOCKALLOC | PGO_NOTIMESTAMP | PGO_GLOCKHELD); if (error) { goto out; } /* * now allocate the range. */ error = GOP_ALLOC(vp, off, len, flags, cred); genfs_node_unlock(vp); /* * if the allocation succeeded, clear PG_CLEAN on all the pages * and clear PG_RDONLY on any pages that are now fully backed * by disk blocks. if the allocation failed, we do not invalidate * the pages since they might have already existed and been dirty, * in which case we need to keep them around. if we created the pages, * they will be clean and read-only, and leaving such pages * in the cache won't cause any problems. */ GOP_SIZE(vp, off + len, &eob, 0); mutex_enter(uobj->vmobjlock); mutex_enter(&uvm_pageqlock); for (i = 0; i < npages; i++) { KASSERT((pgs[i]->flags & PG_RELEASED) == 0); if (!error) { if (off <= pagestart + (i << PAGE_SHIFT) && pagestart + ((i + 1) << PAGE_SHIFT) <= eob) { pgs[i]->flags &= ~PG_RDONLY; } pgs[i]->flags &= ~PG_CLEAN; } uvm_pageactivate(pgs[i]); } mutex_exit(&uvm_pageqlock); uvm_page_unbusy(pgs, npages); mutex_exit(uobj->vmobjlock); out: kmem_free(pgs, pgssize); return error; }