fallocate should be a file operation
Currently all filesystems except XFS implement fallocate asynchronously,
while XFS forced a commit. Both of these are suboptimal - in case of O_SYNC
I/O we really want our allocation on disk, especially for the !KEEP_SIZE
case where we actually grow the file with user-visible zeroes. On the
other hand always commiting the transaction is a bad idea for fast-path
uses of fallocate like for example in recent Samba versions. Given
that block allocation is a data plane operation anyway change it from
an inode operation to a file operation so that we have the file structure
available that lets us check for O_SYNC.
This also includes moving the code around for a few of the filesystems,
and remove the already unnedded S_ISDIR checks given that we only wire
up fallocate for regular files.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c
index fca6689..7cfdcb9 100644
--- a/fs/gfs2/file.c
+++ b/fs/gfs2/file.c
@@ -19,6 +19,8 @@
#include <linux/fs.h>
#include <linux/gfs2_ondisk.h>
#include <linux/ext2_fs.h>
+#include <linux/falloc.h>
+#include <linux/swap.h>
#include <linux/crc32.h>
#include <linux/writeback.h>
#include <asm/uaccess.h>
@@ -610,6 +612,260 @@
return generic_file_aio_write(iocb, iov, nr_segs, pos);
}
+static void empty_write_end(struct page *page, unsigned from,
+ unsigned to)
+{
+ struct gfs2_inode *ip = GFS2_I(page->mapping->host);
+
+ page_zero_new_buffers(page, from, to);
+ flush_dcache_page(page);
+ mark_page_accessed(page);
+
+ if (!gfs2_is_writeback(ip))
+ gfs2_page_add_databufs(ip, page, from, to);
+
+ block_commit_write(page, from, to);
+}
+
+static int write_empty_blocks(struct page *page, unsigned from, unsigned to)
+{
+ unsigned start, end, next;
+ struct buffer_head *bh, *head;
+ int error;
+
+ if (!page_has_buffers(page)) {
+ error = __block_write_begin(page, from, to - from, gfs2_block_map);
+ if (unlikely(error))
+ return error;
+
+ empty_write_end(page, from, to);
+ return 0;
+ }
+
+ bh = head = page_buffers(page);
+ next = end = 0;
+ while (next < from) {
+ next += bh->b_size;
+ bh = bh->b_this_page;
+ }
+ start = next;
+ do {
+ next += bh->b_size;
+ if (buffer_mapped(bh)) {
+ if (end) {
+ error = __block_write_begin(page, start, end - start,
+ gfs2_block_map);
+ if (unlikely(error))
+ return error;
+ empty_write_end(page, start, end);
+ end = 0;
+ }
+ start = next;
+ }
+ else
+ end = next;
+ bh = bh->b_this_page;
+ } while (next < to);
+
+ if (end) {
+ error = __block_write_begin(page, start, end - start, gfs2_block_map);
+ if (unlikely(error))
+ return error;
+ empty_write_end(page, start, end);
+ }
+
+ return 0;
+}
+
+static int fallocate_chunk(struct inode *inode, loff_t offset, loff_t len,
+ int mode)
+{
+ struct gfs2_inode *ip = GFS2_I(inode);
+ struct buffer_head *dibh;
+ int error;
+ u64 start = offset >> PAGE_CACHE_SHIFT;
+ unsigned int start_offset = offset & ~PAGE_CACHE_MASK;
+ u64 end = (offset + len - 1) >> PAGE_CACHE_SHIFT;
+ pgoff_t curr;
+ struct page *page;
+ unsigned int end_offset = (offset + len) & ~PAGE_CACHE_MASK;
+ unsigned int from, to;
+
+ if (!end_offset)
+ end_offset = PAGE_CACHE_SIZE;
+
+ error = gfs2_meta_inode_buffer(ip, &dibh);
+ if (unlikely(error))
+ goto out;
+
+ gfs2_trans_add_bh(ip->i_gl, dibh, 1);
+
+ if (gfs2_is_stuffed(ip)) {
+ error = gfs2_unstuff_dinode(ip, NULL);
+ if (unlikely(error))
+ goto out;
+ }
+
+ curr = start;
+ offset = start << PAGE_CACHE_SHIFT;
+ from = start_offset;
+ to = PAGE_CACHE_SIZE;
+ while (curr <= end) {
+ page = grab_cache_page_write_begin(inode->i_mapping, curr,
+ AOP_FLAG_NOFS);
+ if (unlikely(!page)) {
+ error = -ENOMEM;
+ goto out;
+ }
+
+ if (curr == end)
+ to = end_offset;
+ error = write_empty_blocks(page, from, to);
+ if (!error && offset + to > inode->i_size &&
+ !(mode & FALLOC_FL_KEEP_SIZE)) {
+ i_size_write(inode, offset + to);
+ }
+ unlock_page(page);
+ page_cache_release(page);
+ if (error)
+ goto out;
+ curr++;
+ offset += PAGE_CACHE_SIZE;
+ from = 0;
+ }
+
+ gfs2_dinode_out(ip, dibh->b_data);
+ mark_inode_dirty(inode);
+
+ brelse(dibh);
+
+out:
+ return error;
+}
+
+static void calc_max_reserv(struct gfs2_inode *ip, loff_t max, loff_t *len,
+ unsigned int *data_blocks, unsigned int *ind_blocks)
+{
+ const struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
+ unsigned int max_blocks = ip->i_alloc->al_rgd->rd_free_clone;
+ unsigned int tmp, max_data = max_blocks - 3 * (sdp->sd_max_height - 1);
+
+ for (tmp = max_data; tmp > sdp->sd_diptrs;) {
+ tmp = DIV_ROUND_UP(tmp, sdp->sd_inptrs);
+ max_data -= tmp;
+ }
+ /* This calculation isn't the exact reverse of gfs2_write_calc_reserve,
+ so it might end up with fewer data blocks */
+ if (max_data <= *data_blocks)
+ return;
+ *data_blocks = max_data;
+ *ind_blocks = max_blocks - max_data;
+ *len = ((loff_t)max_data - 3) << sdp->sd_sb.sb_bsize_shift;
+ if (*len > max) {
+ *len = max;
+ gfs2_write_calc_reserv(ip, max, data_blocks, ind_blocks);
+ }
+}
+
+static long gfs2_fallocate(struct file *file, int mode, loff_t offset,
+ loff_t len)
+{
+ struct inode *inode = file->f_path.dentry->d_inode;
+ struct gfs2_sbd *sdp = GFS2_SB(inode);
+ struct gfs2_inode *ip = GFS2_I(inode);
+ unsigned int data_blocks = 0, ind_blocks = 0, rblocks;
+ loff_t bytes, max_bytes;
+ struct gfs2_alloc *al;
+ int error;
+ loff_t next = (offset + len - 1) >> sdp->sd_sb.sb_bsize_shift;
+ next = (next + 1) << sdp->sd_sb.sb_bsize_shift;
+
+ /* We only support the FALLOC_FL_KEEP_SIZE mode */
+ if (mode & ~FALLOC_FL_KEEP_SIZE)
+ return -EOPNOTSUPP;
+
+ offset = (offset >> sdp->sd_sb.sb_bsize_shift) <<
+ sdp->sd_sb.sb_bsize_shift;
+
+ len = next - offset;
+ bytes = sdp->sd_max_rg_data * sdp->sd_sb.sb_bsize / 2;
+ if (!bytes)
+ bytes = UINT_MAX;
+
+ gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &ip->i_gh);
+ error = gfs2_glock_nq(&ip->i_gh);
+ if (unlikely(error))
+ goto out_uninit;
+
+ if (!gfs2_write_alloc_required(ip, offset, len))
+ goto out_unlock;
+
+ while (len > 0) {
+ if (len < bytes)
+ bytes = len;
+ al = gfs2_alloc_get(ip);
+ if (!al) {
+ error = -ENOMEM;
+ goto out_unlock;
+ }
+
+ error = gfs2_quota_lock_check(ip);
+ if (error)
+ goto out_alloc_put;
+
+retry:
+ gfs2_write_calc_reserv(ip, bytes, &data_blocks, &ind_blocks);
+
+ al->al_requested = data_blocks + ind_blocks;
+ error = gfs2_inplace_reserve(ip);
+ if (error) {
+ if (error == -ENOSPC && bytes > sdp->sd_sb.sb_bsize) {
+ bytes >>= 1;
+ goto retry;
+ }
+ goto out_qunlock;
+ }
+ max_bytes = bytes;
+ calc_max_reserv(ip, len, &max_bytes, &data_blocks, &ind_blocks);
+ al->al_requested = data_blocks + ind_blocks;
+
+ rblocks = RES_DINODE + ind_blocks + RES_STATFS + RES_QUOTA +
+ RES_RG_HDR + gfs2_rg_blocks(al);
+ if (gfs2_is_jdata(ip))
+ rblocks += data_blocks ? data_blocks : 1;
+
+ error = gfs2_trans_begin(sdp, rblocks,
+ PAGE_CACHE_SIZE/sdp->sd_sb.sb_bsize);
+ if (error)
+ goto out_trans_fail;
+
+ error = fallocate_chunk(inode, offset, max_bytes, mode);
+ gfs2_trans_end(sdp);
+
+ if (error)
+ goto out_trans_fail;
+
+ len -= max_bytes;
+ offset += max_bytes;
+ gfs2_inplace_release(ip);
+ gfs2_quota_unlock(ip);
+ gfs2_alloc_put(ip);
+ }
+ goto out_unlock;
+
+out_trans_fail:
+ gfs2_inplace_release(ip);
+out_qunlock:
+ gfs2_quota_unlock(ip);
+out_alloc_put:
+ gfs2_alloc_put(ip);
+out_unlock:
+ gfs2_glock_dq(&ip->i_gh);
+out_uninit:
+ gfs2_holder_uninit(&ip->i_gh);
+ return error;
+}
+
#ifdef CONFIG_GFS2_FS_LOCKING_DLM
/**
@@ -765,6 +1021,7 @@
.splice_read = generic_file_splice_read,
.splice_write = generic_file_splice_write,
.setlease = gfs2_setlease,
+ .fallocate = gfs2_fallocate,
};
const struct file_operations gfs2_dir_fops = {
@@ -794,6 +1051,7 @@
.splice_read = generic_file_splice_read,
.splice_write = generic_file_splice_write,
.setlease = generic_setlease,
+ .fallocate = gfs2_fallocate,
};
const struct file_operations gfs2_dir_fops_nolock = {
diff --git a/fs/gfs2/ops_inode.c b/fs/gfs2/ops_inode.c
index c09528c..d8b26ac 100644
--- a/fs/gfs2/ops_inode.c
+++ b/fs/gfs2/ops_inode.c
@@ -18,8 +18,6 @@
#include <linux/gfs2_ondisk.h>
#include <linux/crc32.h>
#include <linux/fiemap.h>
-#include <linux/swap.h>
-#include <linux/falloc.h>
#include <asm/uaccess.h>
#include "gfs2.h"
@@ -1257,261 +1255,6 @@
return ret;
}
-static void empty_write_end(struct page *page, unsigned from,
- unsigned to)
-{
- struct gfs2_inode *ip = GFS2_I(page->mapping->host);
-
- page_zero_new_buffers(page, from, to);
- flush_dcache_page(page);
- mark_page_accessed(page);
-
- if (!gfs2_is_writeback(ip))
- gfs2_page_add_databufs(ip, page, from, to);
-
- block_commit_write(page, from, to);
-}
-
-
-static int write_empty_blocks(struct page *page, unsigned from, unsigned to)
-{
- unsigned start, end, next;
- struct buffer_head *bh, *head;
- int error;
-
- if (!page_has_buffers(page)) {
- error = __block_write_begin(page, from, to - from, gfs2_block_map);
- if (unlikely(error))
- return error;
-
- empty_write_end(page, from, to);
- return 0;
- }
-
- bh = head = page_buffers(page);
- next = end = 0;
- while (next < from) {
- next += bh->b_size;
- bh = bh->b_this_page;
- }
- start = next;
- do {
- next += bh->b_size;
- if (buffer_mapped(bh)) {
- if (end) {
- error = __block_write_begin(page, start, end - start,
- gfs2_block_map);
- if (unlikely(error))
- return error;
- empty_write_end(page, start, end);
- end = 0;
- }
- start = next;
- }
- else
- end = next;
- bh = bh->b_this_page;
- } while (next < to);
-
- if (end) {
- error = __block_write_begin(page, start, end - start, gfs2_block_map);
- if (unlikely(error))
- return error;
- empty_write_end(page, start, end);
- }
-
- return 0;
-}
-
-static int fallocate_chunk(struct inode *inode, loff_t offset, loff_t len,
- int mode)
-{
- struct gfs2_inode *ip = GFS2_I(inode);
- struct buffer_head *dibh;
- int error;
- u64 start = offset >> PAGE_CACHE_SHIFT;
- unsigned int start_offset = offset & ~PAGE_CACHE_MASK;
- u64 end = (offset + len - 1) >> PAGE_CACHE_SHIFT;
- pgoff_t curr;
- struct page *page;
- unsigned int end_offset = (offset + len) & ~PAGE_CACHE_MASK;
- unsigned int from, to;
-
- if (!end_offset)
- end_offset = PAGE_CACHE_SIZE;
-
- error = gfs2_meta_inode_buffer(ip, &dibh);
- if (unlikely(error))
- goto out;
-
- gfs2_trans_add_bh(ip->i_gl, dibh, 1);
-
- if (gfs2_is_stuffed(ip)) {
- error = gfs2_unstuff_dinode(ip, NULL);
- if (unlikely(error))
- goto out;
- }
-
- curr = start;
- offset = start << PAGE_CACHE_SHIFT;
- from = start_offset;
- to = PAGE_CACHE_SIZE;
- while (curr <= end) {
- page = grab_cache_page_write_begin(inode->i_mapping, curr,
- AOP_FLAG_NOFS);
- if (unlikely(!page)) {
- error = -ENOMEM;
- goto out;
- }
-
- if (curr == end)
- to = end_offset;
- error = write_empty_blocks(page, from, to);
- if (!error && offset + to > inode->i_size &&
- !(mode & FALLOC_FL_KEEP_SIZE)) {
- i_size_write(inode, offset + to);
- }
- unlock_page(page);
- page_cache_release(page);
- if (error)
- goto out;
- curr++;
- offset += PAGE_CACHE_SIZE;
- from = 0;
- }
-
- gfs2_dinode_out(ip, dibh->b_data);
- mark_inode_dirty(inode);
-
- brelse(dibh);
-
-out:
- return error;
-}
-
-static void calc_max_reserv(struct gfs2_inode *ip, loff_t max, loff_t *len,
- unsigned int *data_blocks, unsigned int *ind_blocks)
-{
- const struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
- unsigned int max_blocks = ip->i_alloc->al_rgd->rd_free_clone;
- unsigned int tmp, max_data = max_blocks - 3 * (sdp->sd_max_height - 1);
-
- for (tmp = max_data; tmp > sdp->sd_diptrs;) {
- tmp = DIV_ROUND_UP(tmp, sdp->sd_inptrs);
- max_data -= tmp;
- }
- /* This calculation isn't the exact reverse of gfs2_write_calc_reserve,
- so it might end up with fewer data blocks */
- if (max_data <= *data_blocks)
- return;
- *data_blocks = max_data;
- *ind_blocks = max_blocks - max_data;
- *len = ((loff_t)max_data - 3) << sdp->sd_sb.sb_bsize_shift;
- if (*len > max) {
- *len = max;
- gfs2_write_calc_reserv(ip, max, data_blocks, ind_blocks);
- }
-}
-
-static long gfs2_fallocate(struct inode *inode, int mode, loff_t offset,
- loff_t len)
-{
- struct gfs2_sbd *sdp = GFS2_SB(inode);
- struct gfs2_inode *ip = GFS2_I(inode);
- unsigned int data_blocks = 0, ind_blocks = 0, rblocks;
- loff_t bytes, max_bytes;
- struct gfs2_alloc *al;
- int error;
- loff_t next = (offset + len - 1) >> sdp->sd_sb.sb_bsize_shift;
- next = (next + 1) << sdp->sd_sb.sb_bsize_shift;
-
- /* We only support the FALLOC_FL_KEEP_SIZE mode */
- if (mode & ~FALLOC_FL_KEEP_SIZE)
- return -EOPNOTSUPP;
-
- offset = (offset >> sdp->sd_sb.sb_bsize_shift) <<
- sdp->sd_sb.sb_bsize_shift;
-
- len = next - offset;
- bytes = sdp->sd_max_rg_data * sdp->sd_sb.sb_bsize / 2;
- if (!bytes)
- bytes = UINT_MAX;
-
- gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &ip->i_gh);
- error = gfs2_glock_nq(&ip->i_gh);
- if (unlikely(error))
- goto out_uninit;
-
- if (!gfs2_write_alloc_required(ip, offset, len))
- goto out_unlock;
-
- while (len > 0) {
- if (len < bytes)
- bytes = len;
- al = gfs2_alloc_get(ip);
- if (!al) {
- error = -ENOMEM;
- goto out_unlock;
- }
-
- error = gfs2_quota_lock_check(ip);
- if (error)
- goto out_alloc_put;
-
-retry:
- gfs2_write_calc_reserv(ip, bytes, &data_blocks, &ind_blocks);
-
- al->al_requested = data_blocks + ind_blocks;
- error = gfs2_inplace_reserve(ip);
- if (error) {
- if (error == -ENOSPC && bytes > sdp->sd_sb.sb_bsize) {
- bytes >>= 1;
- goto retry;
- }
- goto out_qunlock;
- }
- max_bytes = bytes;
- calc_max_reserv(ip, len, &max_bytes, &data_blocks, &ind_blocks);
- al->al_requested = data_blocks + ind_blocks;
-
- rblocks = RES_DINODE + ind_blocks + RES_STATFS + RES_QUOTA +
- RES_RG_HDR + gfs2_rg_blocks(al);
- if (gfs2_is_jdata(ip))
- rblocks += data_blocks ? data_blocks : 1;
-
- error = gfs2_trans_begin(sdp, rblocks,
- PAGE_CACHE_SIZE/sdp->sd_sb.sb_bsize);
- if (error)
- goto out_trans_fail;
-
- error = fallocate_chunk(inode, offset, max_bytes, mode);
- gfs2_trans_end(sdp);
-
- if (error)
- goto out_trans_fail;
-
- len -= max_bytes;
- offset += max_bytes;
- gfs2_inplace_release(ip);
- gfs2_quota_unlock(ip);
- gfs2_alloc_put(ip);
- }
- goto out_unlock;
-
-out_trans_fail:
- gfs2_inplace_release(ip);
-out_qunlock:
- gfs2_quota_unlock(ip);
-out_alloc_put:
- gfs2_alloc_put(ip);
-out_unlock:
- gfs2_glock_dq(&ip->i_gh);
-out_uninit:
- gfs2_holder_uninit(&ip->i_gh);
- return error;
-}
-
-
static int gfs2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
u64 start, u64 len)
{
@@ -1562,7 +1305,6 @@
.getxattr = gfs2_getxattr,
.listxattr = gfs2_listxattr,
.removexattr = gfs2_removexattr,
- .fallocate = gfs2_fallocate,
.fiemap = gfs2_fiemap,
};