ioctl.c 5.3 KB

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  1. /*
  2. * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
  3. */
  4. #include <linux/capability.h>
  5. #include <linux/fs.h>
  6. #include <linux/mount.h>
  7. #include "reiserfs.h"
  8. #include <linux/time.h>
  9. #include <linux/uaccess.h>
  10. #include <linux/pagemap.h>
  11. #include <linux/compat.h>
  12. /*
  13. * reiserfs_ioctl - handler for ioctl for inode
  14. * supported commands:
  15. * 1) REISERFS_IOC_UNPACK - try to unpack tail from direct item into indirect
  16. * and prevent packing file (argument arg has t
  17. * be non-zero)
  18. * 2) REISERFS_IOC_[GS]ETFLAGS, REISERFS_IOC_[GS]ETVERSION
  19. * 3) That's all for a while ...
  20. */
  21. long reiserfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
  22. {
  23. struct inode *inode = file_inode(filp);
  24. unsigned int flags;
  25. int err = 0;
  26. reiserfs_write_lock(inode->i_sb);
  27. switch (cmd) {
  28. case REISERFS_IOC_UNPACK:
  29. if (S_ISREG(inode->i_mode)) {
  30. if (arg)
  31. err = reiserfs_unpack(inode, filp);
  32. } else
  33. err = -ENOTTY;
  34. break;
  35. /*
  36. * following two cases are taken from fs/ext2/ioctl.c by Remy
  37. * Card (card@masi.ibp.fr)
  38. */
  39. case REISERFS_IOC_GETFLAGS:
  40. if (!reiserfs_attrs(inode->i_sb)) {
  41. err = -ENOTTY;
  42. break;
  43. }
  44. flags = REISERFS_I(inode)->i_attrs;
  45. err = put_user(flags, (int __user *)arg);
  46. break;
  47. case REISERFS_IOC_SETFLAGS:{
  48. if (!reiserfs_attrs(inode->i_sb)) {
  49. err = -ENOTTY;
  50. break;
  51. }
  52. err = mnt_want_write_file(filp);
  53. if (err)
  54. break;
  55. if (!inode_owner_or_capable(inode)) {
  56. err = -EPERM;
  57. goto setflags_out;
  58. }
  59. if (get_user(flags, (int __user *)arg)) {
  60. err = -EFAULT;
  61. goto setflags_out;
  62. }
  63. /*
  64. * Is it quota file? Do not allow user to mess with it
  65. */
  66. if (IS_NOQUOTA(inode)) {
  67. err = -EPERM;
  68. goto setflags_out;
  69. }
  70. err = vfs_ioc_setflags_prepare(inode,
  71. REISERFS_I(inode)->i_attrs,
  72. flags);
  73. if (err)
  74. goto setflags_out;
  75. if ((flags & REISERFS_NOTAIL_FL) &&
  76. S_ISREG(inode->i_mode)) {
  77. int result;
  78. result = reiserfs_unpack(inode, filp);
  79. if (result) {
  80. err = result;
  81. goto setflags_out;
  82. }
  83. }
  84. sd_attrs_to_i_attrs(flags, inode);
  85. REISERFS_I(inode)->i_attrs = flags;
  86. inode->i_ctime = current_time(inode);
  87. mark_inode_dirty(inode);
  88. setflags_out:
  89. mnt_drop_write_file(filp);
  90. break;
  91. }
  92. case REISERFS_IOC_GETVERSION:
  93. err = put_user(inode->i_generation, (int __user *)arg);
  94. break;
  95. case REISERFS_IOC_SETVERSION:
  96. if (!inode_owner_or_capable(inode)) {
  97. err = -EPERM;
  98. break;
  99. }
  100. err = mnt_want_write_file(filp);
  101. if (err)
  102. break;
  103. if (get_user(inode->i_generation, (int __user *)arg)) {
  104. err = -EFAULT;
  105. goto setversion_out;
  106. }
  107. inode->i_ctime = current_time(inode);
  108. mark_inode_dirty(inode);
  109. setversion_out:
  110. mnt_drop_write_file(filp);
  111. break;
  112. default:
  113. err = -ENOTTY;
  114. }
  115. reiserfs_write_unlock(inode->i_sb);
  116. return err;
  117. }
  118. #ifdef CONFIG_COMPAT
  119. long reiserfs_compat_ioctl(struct file *file, unsigned int cmd,
  120. unsigned long arg)
  121. {
  122. /*
  123. * These are just misnamed, they actually
  124. * get/put from/to user an int
  125. */
  126. switch (cmd) {
  127. case REISERFS_IOC32_UNPACK:
  128. cmd = REISERFS_IOC_UNPACK;
  129. break;
  130. case REISERFS_IOC32_GETFLAGS:
  131. cmd = REISERFS_IOC_GETFLAGS;
  132. break;
  133. case REISERFS_IOC32_SETFLAGS:
  134. cmd = REISERFS_IOC_SETFLAGS;
  135. break;
  136. case REISERFS_IOC32_GETVERSION:
  137. cmd = REISERFS_IOC_GETVERSION;
  138. break;
  139. case REISERFS_IOC32_SETVERSION:
  140. cmd = REISERFS_IOC_SETVERSION;
  141. break;
  142. default:
  143. return -ENOIOCTLCMD;
  144. }
  145. return reiserfs_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
  146. }
  147. #endif
  148. int reiserfs_commit_write(struct file *f, struct page *page,
  149. unsigned from, unsigned to);
  150. /*
  151. * reiserfs_unpack
  152. * Function try to convert tail from direct item into indirect.
  153. * It set up nopack attribute in the REISERFS_I(inode)->nopack
  154. */
  155. int reiserfs_unpack(struct inode *inode, struct file *filp)
  156. {
  157. int retval = 0;
  158. int index;
  159. struct page *page;
  160. struct address_space *mapping;
  161. unsigned long write_from;
  162. unsigned long blocksize = inode->i_sb->s_blocksize;
  163. if (inode->i_size == 0) {
  164. REISERFS_I(inode)->i_flags |= i_nopack_mask;
  165. return 0;
  166. }
  167. /* ioctl already done */
  168. if (REISERFS_I(inode)->i_flags & i_nopack_mask) {
  169. return 0;
  170. }
  171. /* we need to make sure nobody is changing the file size beneath us */
  172. {
  173. int depth = reiserfs_write_unlock_nested(inode->i_sb);
  174. inode_lock(inode);
  175. reiserfs_write_lock_nested(inode->i_sb, depth);
  176. }
  177. reiserfs_write_lock(inode->i_sb);
  178. write_from = inode->i_size & (blocksize - 1);
  179. /* if we are on a block boundary, we are already unpacked. */
  180. if (write_from == 0) {
  181. REISERFS_I(inode)->i_flags |= i_nopack_mask;
  182. goto out;
  183. }
  184. /*
  185. * we unpack by finding the page with the tail, and calling
  186. * __reiserfs_write_begin on that page. This will force a
  187. * reiserfs_get_block to unpack the tail for us.
  188. */
  189. index = inode->i_size >> PAGE_SHIFT;
  190. mapping = inode->i_mapping;
  191. page = grab_cache_page(mapping, index);
  192. retval = -ENOMEM;
  193. if (!page) {
  194. goto out;
  195. }
  196. retval = __reiserfs_write_begin(page, write_from, 0);
  197. if (retval)
  198. goto out_unlock;
  199. /* conversion can change page contents, must flush */
  200. flush_dcache_page(page);
  201. retval = reiserfs_commit_write(NULL, page, write_from, write_from);
  202. REISERFS_I(inode)->i_flags |= i_nopack_mask;
  203. out_unlock:
  204. unlock_page(page);
  205. put_page(page);
  206. out:
  207. inode_unlock(inode);
  208. reiserfs_write_unlock(inode->i_sb);
  209. return retval;
  210. }