| /* |
| * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. |
| * Copyright (C) 2004-2006 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/sched.h> |
| #include <linux/slab.h> |
| #include <linux/spinlock.h> |
| #include <linux/completion.h> |
| #include <linux/buffer_head.h> |
| #include <linux/mm.h> |
| #include <linux/pagemap.h> |
| #include <linux/gfs2_ondisk.h> |
| #include <linux/lm_interface.h> |
| |
| #include "gfs2.h" |
| #include "incore.h" |
| #include "bmap.h" |
| #include "glock.h" |
| #include "inode.h" |
| #include "ops_vm.h" |
| #include "quota.h" |
| #include "rgrp.h" |
| #include "trans.h" |
| #include "util.h" |
| |
| static void pfault_be_greedy(struct gfs2_inode *ip) |
| { |
| unsigned int time; |
| |
| spin_lock(&ip->i_spin); |
| time = ip->i_greedy; |
| ip->i_last_pfault = jiffies; |
| spin_unlock(&ip->i_spin); |
| |
| igrab(&ip->i_inode); |
| if (gfs2_glock_be_greedy(ip->i_gl, time)) |
| iput(&ip->i_inode); |
| } |
| |
| static struct page *gfs2_private_nopage(struct vm_area_struct *area, |
| unsigned long address, int *type) |
| { |
| struct gfs2_inode *ip = GFS2_I(area->vm_file->f_mapping->host); |
| struct page *result; |
| |
| set_bit(GIF_PAGED, &ip->i_flags); |
| |
| result = filemap_nopage(area, address, type); |
| |
| if (result && result != NOPAGE_OOM) |
| pfault_be_greedy(ip); |
| |
| return result; |
| } |
| |
| static int alloc_page_backing(struct gfs2_inode *ip, struct page *page) |
| { |
| struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); |
| unsigned long index = page->index; |
| u64 lblock = index << (PAGE_CACHE_SHIFT - |
| sdp->sd_sb.sb_bsize_shift); |
| unsigned int blocks = PAGE_CACHE_SIZE >> sdp->sd_sb.sb_bsize_shift; |
| struct gfs2_alloc *al; |
| unsigned int data_blocks, ind_blocks; |
| unsigned int x; |
| int error; |
| |
| al = gfs2_alloc_get(ip); |
| |
| error = gfs2_quota_lock(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE); |
| if (error) |
| goto out; |
| |
| error = gfs2_quota_check(ip, ip->i_inode.i_uid, ip->i_inode.i_gid); |
| if (error) |
| goto out_gunlock_q; |
| |
| gfs2_write_calc_reserv(ip, PAGE_CACHE_SIZE, &data_blocks, &ind_blocks); |
| |
| al->al_requested = data_blocks + ind_blocks; |
| |
| error = gfs2_inplace_reserve(ip); |
| if (error) |
| goto out_gunlock_q; |
| |
| error = gfs2_trans_begin(sdp, al->al_rgd->rd_ri.ri_length + |
| ind_blocks + RES_DINODE + |
| RES_STATFS + RES_QUOTA, 0); |
| if (error) |
| goto out_ipres; |
| |
| if (gfs2_is_stuffed(ip)) { |
| error = gfs2_unstuff_dinode(ip, NULL); |
| if (error) |
| goto out_trans; |
| } |
| |
| for (x = 0; x < blocks; ) { |
| u64 dblock; |
| unsigned int extlen; |
| int new = 1; |
| |
| error = gfs2_extent_map(&ip->i_inode, lblock, &new, &dblock, &extlen); |
| if (error) |
| goto out_trans; |
| |
| lblock += extlen; |
| x += extlen; |
| } |
| |
| gfs2_assert_warn(sdp, al->al_alloced); |
| |
| out_trans: |
| gfs2_trans_end(sdp); |
| out_ipres: |
| gfs2_inplace_release(ip); |
| out_gunlock_q: |
| gfs2_quota_unlock(ip); |
| out: |
| gfs2_alloc_put(ip); |
| return error; |
| } |
| |
| static struct page *gfs2_sharewrite_nopage(struct vm_area_struct *area, |
| unsigned long address, int *type) |
| { |
| struct file *file = area->vm_file; |
| struct gfs2_file *gf = file->private_data; |
| struct gfs2_inode *ip = GFS2_I(file->f_mapping->host); |
| struct gfs2_holder i_gh; |
| struct page *result = NULL; |
| unsigned long index = ((address - area->vm_start) >> PAGE_CACHE_SHIFT) + |
| area->vm_pgoff; |
| int alloc_required; |
| int error; |
| |
| error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh); |
| if (error) |
| return NULL; |
| |
| set_bit(GIF_PAGED, &ip->i_flags); |
| set_bit(GIF_SW_PAGED, &ip->i_flags); |
| |
| error = gfs2_write_alloc_required(ip, (u64)index << PAGE_CACHE_SHIFT, |
| PAGE_CACHE_SIZE, &alloc_required); |
| if (error) |
| goto out; |
| |
| set_bit(GFF_EXLOCK, &gf->f_flags); |
| result = filemap_nopage(area, address, type); |
| clear_bit(GFF_EXLOCK, &gf->f_flags); |
| if (!result || result == NOPAGE_OOM) |
| goto out; |
| |
| if (alloc_required) { |
| error = alloc_page_backing(ip, result); |
| if (error) { |
| page_cache_release(result); |
| result = NULL; |
| goto out; |
| } |
| set_page_dirty(result); |
| } |
| |
| pfault_be_greedy(ip); |
| out: |
| gfs2_glock_dq_uninit(&i_gh); |
| |
| return result; |
| } |
| |
| struct vm_operations_struct gfs2_vm_ops_private = { |
| .nopage = gfs2_private_nopage, |
| }; |
| |
| struct vm_operations_struct gfs2_vm_ops_sharewrite = { |
| .nopage = gfs2_sharewrite_nopage, |
| }; |
| |