diff options
Diffstat (limited to 'fs/gfs2/ops_vm.c')
| -rw-r--r-- | fs/gfs2/ops_vm.c | 184 |
1 files changed, 184 insertions, 0 deletions
diff --git a/fs/gfs2/ops_vm.c b/fs/gfs2/ops_vm.c new file mode 100644 index 000000000000..5453d2947ab3 --- /dev/null +++ b/fs/gfs2/ops_vm.c @@ -0,0 +1,184 @@ +/* + * 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_di.di_uid, ip->i_di.di_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, +}; + |