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26#include <linux/module.h>
27#include <linux/errno.h>
28#include <linux/fs.h>
29#include <linux/file.h>
30#include <linux/stat.h>
31#include <linux/string.h>
32#include <linux/inet.h>
33#include <linux/pagemap.h>
34#include <linux/idr.h>
35#include <linux/sched.h>
36#include <net/9p/9p.h>
37#include <net/9p/client.h>
38
39#include "v9fs.h"
40#include "v9fs_vfs.h"
41#include "cache.h"
42
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50
51static int v9fs_vfs_readpage(struct file *filp, struct page *page)
52{
53 int retval;
54 loff_t offset;
55 char *buffer;
56 struct inode *inode;
57
58 inode = page->mapping->host;
59 P9_DPRINTK(P9_DEBUG_VFS, "\n");
60
61 BUG_ON(!PageLocked(page));
62
63 retval = v9fs_readpage_from_fscache(inode, page);
64 if (retval == 0)
65 return retval;
66
67 buffer = kmap(page);
68 offset = page_offset(page);
69
70 retval = v9fs_file_readn(filp, buffer, NULL, PAGE_CACHE_SIZE, offset);
71 if (retval < 0) {
72 v9fs_uncache_page(inode, page);
73 goto done;
74 }
75
76 memset(buffer + retval, 0, PAGE_CACHE_SIZE - retval);
77 flush_dcache_page(page);
78 SetPageUptodate(page);
79
80 v9fs_readpage_to_fscache(inode, page);
81 retval = 0;
82
83done:
84 kunmap(page);
85 unlock_page(page);
86 return retval;
87}
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98
99static int v9fs_vfs_readpages(struct file *filp, struct address_space *mapping,
100 struct list_head *pages, unsigned nr_pages)
101{
102 int ret = 0;
103 struct inode *inode;
104
105 inode = mapping->host;
106 P9_DPRINTK(P9_DEBUG_VFS, "inode: %p file: %p\n", inode, filp);
107
108 ret = v9fs_readpages_from_fscache(inode, mapping, pages, &nr_pages);
109 if (ret == 0)
110 return ret;
111
112 ret = read_cache_pages(mapping, pages, (void *)v9fs_vfs_readpage, filp);
113 P9_DPRINTK(P9_DEBUG_VFS, " = %d\n", ret);
114 return ret;
115}
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122
123static int v9fs_release_page(struct page *page, gfp_t gfp)
124{
125 if (PagePrivate(page))
126 return 0;
127
128 return v9fs_fscache_release_page(page, gfp);
129}
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137
138static void v9fs_invalidate_page(struct page *page, unsigned long offset)
139{
140 if (offset == 0)
141 v9fs_fscache_invalidate_page(page);
142}
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151
152static int v9fs_launder_page(struct page *page)
153{
154 return 0;
155}
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176ssize_t v9fs_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov,
177 loff_t pos, unsigned long nr_segs)
178{
179 P9_DPRINTK(P9_DEBUG_VFS, "v9fs_direct_IO: v9fs_direct_IO (%s) "
180 "off/no(%lld/%lu) EINVAL\n",
181 iocb->ki_filp->f_path.dentry->d_name.name,
182 (long long) pos, nr_segs);
183
184 return -EINVAL;
185}
186const struct address_space_operations v9fs_addr_operations = {
187 .readpage = v9fs_vfs_readpage,
188 .readpages = v9fs_vfs_readpages,
189 .releasepage = v9fs_release_page,
190 .invalidatepage = v9fs_invalidate_page,
191 .launder_page = v9fs_launder_page,
192 .direct_IO = v9fs_direct_IO,
193};
194