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  1. /*
  2.  * Copyright (c) 2008 Jakub Jermar
  3.  * All rights reserved.
  4.  *
  5.  * Redistribution and use in source and binary forms, with or without
  6.  * modification, are permitted provided that the following conditions
  7.  * are met:
  8.  *
  9.  * - Redistributions of source code must retain the above copyright
  10.  *   notice, this list of conditions and the following disclaimer.
  11.  * - Redistributions in binary form must reproduce the above copyright
  12.  *   notice, this list of conditions and the following disclaimer in the
  13.  *   documentation and/or other materials provided with the distribution.
  14.  * - The name of the author may not be used to endorse or promote products
  15.  *   derived from this software without specific prior written permission.
  16.  *
  17.  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  18.  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  19.  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  20.  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  21.  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  22.  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23.  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24.  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25.  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26.  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27.  */
  28.  
  29. /** @addtogroup fs
  30.  * @{
  31.  */
  32.  
  33. /**
  34.  * @file    tmpfs_ops.c
  35.  * @brief   Implementation of VFS operations for the TMPFS file system
  36.  *      server.
  37.  */
  38.  
  39. #include "tmpfs.h"
  40. #include "../../vfs/vfs.h"
  41. #include <ipc/ipc.h>
  42. #include <async.h>
  43. #include <errno.h>
  44. #include <atomic.h>
  45. #include <stdlib.h>
  46. #include <string.h>
  47. #include <stdio.h>
  48. #include <assert.h>
  49. #include <sys/types.h>
  50. #include <libadt/hash_table.h>
  51. #include <as.h>
  52. #include <libfs.h>
  53.  
  54. #define min(a, b)       ((a) < (b) ? (a) : (b))
  55. #define max(a, b)       ((a) > (b) ? (a) : (b))
  56.  
  57. #define NODES_BUCKETS   256
  58.  
  59. /** All root nodes have index 0. */
  60. #define TMPFS_SOME_ROOT     0
  61. /** Global counter for assigning node indices. Shared by all instances. */
  62. fs_index_t tmpfs_next_index = 1;
  63.  
  64. /*
  65.  * Implementation of the libfs interface.
  66.  */
  67.  
  68. /* Forward declarations of static functions. */
  69. static fs_node_t *tmpfs_match(fs_node_t *, const char *);
  70. static fs_node_t *tmpfs_node_get(dev_handle_t, fs_index_t);
  71. static void tmpfs_node_put(fs_node_t *);
  72. static fs_node_t *tmpfs_create_node(dev_handle_t, int);
  73. static int tmpfs_link_node(fs_node_t *, fs_node_t *, const char *);
  74. static int tmpfs_unlink_node(fs_node_t *, fs_node_t *, const char *);
  75. static int tmpfs_destroy_node(fs_node_t *);
  76.  
  77. /* Implementation of helper functions. */
  78. static fs_index_t tmpfs_index_get(fs_node_t *fn)
  79. {
  80.     return TMPFS_NODE(fn)->index;
  81. }
  82.  
  83. static size_t tmpfs_size_get(fs_node_t *fn)
  84. {
  85.     return TMPFS_NODE(fn)->size;
  86. }
  87.  
  88. static unsigned tmpfs_lnkcnt_get(fs_node_t *fn)
  89. {
  90.     return TMPFS_NODE(fn)->lnkcnt;
  91. }
  92.  
  93. static bool tmpfs_has_children(fs_node_t *fn)
  94. {
  95.     return !list_empty(&TMPFS_NODE(fn)->cs_head);
  96. }
  97.  
  98. static fs_node_t *tmpfs_root_get(dev_handle_t dev_handle)
  99. {
  100.     return tmpfs_node_get(dev_handle, TMPFS_SOME_ROOT);
  101. }
  102.  
  103. static char tmpfs_plb_get_char(unsigned pos)
  104. {
  105.     return tmpfs_reg.plb_ro[pos % PLB_SIZE];
  106. }
  107.  
  108. static bool tmpfs_is_directory(fs_node_t *fn)
  109. {
  110.     return TMPFS_NODE(fn)->type == TMPFS_DIRECTORY;
  111. }
  112.  
  113. static bool tmpfs_is_file(fs_node_t *fn)
  114. {
  115.     return TMPFS_NODE(fn)->type == TMPFS_FILE;
  116. }
  117.  
  118. /** libfs operations */
  119. libfs_ops_t tmpfs_libfs_ops = {
  120.     .match = tmpfs_match,
  121.     .node_get = tmpfs_node_get,
  122.     .node_put = tmpfs_node_put,
  123.     .create = tmpfs_create_node,
  124.     .destroy = tmpfs_destroy_node,
  125.     .link = tmpfs_link_node,
  126.     .unlink = tmpfs_unlink_node,
  127.     .index_get = tmpfs_index_get,
  128.     .size_get = tmpfs_size_get,
  129.     .lnkcnt_get = tmpfs_lnkcnt_get,
  130.     .has_children = tmpfs_has_children,
  131.     .root_get = tmpfs_root_get,
  132.     .plb_get_char = tmpfs_plb_get_char,
  133.     .is_directory = tmpfs_is_directory,
  134.     .is_file = tmpfs_is_file
  135. };
  136.  
  137. /** Hash table of all TMPFS nodes. */
  138. hash_table_t nodes;
  139.  
  140. #define NODES_KEY_INDEX 0
  141. #define NODES_KEY_DEV   1
  142.  
  143. /* Implementation of hash table interface for the nodes hash table. */
  144. static hash_index_t nodes_hash(unsigned long key[])
  145. {
  146.     return key[NODES_KEY_INDEX] % NODES_BUCKETS;
  147. }
  148.  
  149. static int nodes_compare(unsigned long key[], hash_count_t keys, link_t *item)
  150. {
  151.     tmpfs_node_t *nodep = hash_table_get_instance(item, tmpfs_node_t,
  152.         nh_link);
  153.     return (nodep->index == key[NODES_KEY_INDEX] &&
  154.         nodep->dev_handle == key[NODES_KEY_DEV]);
  155. }
  156.  
  157. static void nodes_remove_callback(link_t *item)
  158. {
  159. }
  160.  
  161. /** TMPFS nodes hash table operations. */
  162. hash_table_operations_t nodes_ops = {
  163.     .hash = nodes_hash,
  164.     .compare = nodes_compare,
  165.     .remove_callback = nodes_remove_callback
  166. };
  167.  
  168. static void tmpfs_node_initialize(tmpfs_node_t *nodep)
  169. {
  170.     nodep->bp = NULL;
  171.     nodep->index = 0;
  172.     nodep->dev_handle = 0;
  173.     nodep->type = TMPFS_NONE;
  174.     nodep->lnkcnt = 0;
  175.     nodep->size = 0;
  176.     nodep->data = NULL;
  177.     link_initialize(&nodep->nh_link);
  178.     list_initialize(&nodep->cs_head);
  179. }
  180.  
  181. static void tmpfs_dentry_initialize(tmpfs_dentry_t *dentryp)
  182. {
  183.     link_initialize(&dentryp->link);
  184.     dentryp->name = NULL;
  185.     dentryp->node = NULL;
  186. }
  187.  
  188. bool tmpfs_init(void)
  189. {
  190.     if (!hash_table_create(&nodes, NODES_BUCKETS, 2, &nodes_ops))
  191.         return false;
  192.    
  193.     return true;
  194. }
  195.  
  196. static bool tmpfs_instance_init(dev_handle_t dev_handle)
  197. {
  198.     fs_node_t *rfn;
  199.    
  200.     rfn = tmpfs_create_node(dev_handle, L_DIRECTORY);
  201.     if (!rfn)
  202.         return false;
  203.     TMPFS_NODE(rfn)->lnkcnt = 0;    /* FS root is not linked */
  204.     return true;
  205. }
  206.  
  207. fs_node_t *tmpfs_match(fs_node_t *pfn, const char *component)
  208. {
  209.     tmpfs_node_t *parentp = TMPFS_NODE(pfn);
  210.     link_t *lnk;
  211.  
  212.     for (lnk = parentp->cs_head.next; lnk != &parentp->cs_head;
  213.         lnk = lnk->next) {
  214.         tmpfs_dentry_t *dentryp = list_get_instance(lnk, tmpfs_dentry_t,
  215.             link);
  216.         if (!str_cmp(dentryp->name, component))
  217.             return FS_NODE(dentryp->node);
  218.     }
  219.  
  220.     return NULL;
  221. }
  222.  
  223. fs_node_t *tmpfs_node_get(dev_handle_t dev_handle, fs_index_t index)
  224. {
  225.     unsigned long key[] = {
  226.         [NODES_KEY_INDEX] = index,
  227.         [NODES_KEY_DEV] = dev_handle
  228.     };
  229.     link_t *lnk = hash_table_find(&nodes, key);
  230.     if (!lnk)
  231.         return NULL;
  232.     return FS_NODE(hash_table_get_instance(lnk, tmpfs_node_t, nh_link));
  233. }
  234.  
  235. void tmpfs_node_put(fs_node_t *fn)
  236. {
  237.     /* nothing to do */
  238. }
  239.  
  240. fs_node_t *tmpfs_create_node(dev_handle_t dev_handle, int lflag)
  241. {
  242.     assert((lflag & L_FILE) ^ (lflag & L_DIRECTORY));
  243.  
  244.     tmpfs_node_t *nodep = malloc(sizeof(tmpfs_node_t));
  245.     if (!nodep)
  246.         return NULL;
  247.     tmpfs_node_initialize(nodep);
  248.     nodep->bp = malloc(sizeof(fs_node_t));
  249.     if (!nodep->bp) {
  250.         free(nodep);
  251.         return NULL;
  252.     }
  253.     nodep->bp->data = nodep;    /* link the FS and TMPFS nodes */
  254.     if (!tmpfs_root_get(dev_handle))
  255.         nodep->index = TMPFS_SOME_ROOT;
  256.     else
  257.         nodep->index = tmpfs_next_index++;
  258.     nodep->dev_handle = dev_handle;
  259.     if (lflag & L_DIRECTORY)
  260.         nodep->type = TMPFS_DIRECTORY;
  261.     else
  262.         nodep->type = TMPFS_FILE;
  263.  
  264.     /* Insert the new node into the nodes hash table. */
  265.     unsigned long key[] = {
  266.         [NODES_KEY_INDEX] = nodep->index,
  267.         [NODES_KEY_DEV] = nodep->dev_handle
  268.     };
  269.     hash_table_insert(&nodes, key, &nodep->nh_link);
  270.     return FS_NODE(nodep);
  271. }
  272.  
  273. int tmpfs_link_node(fs_node_t *pfn, fs_node_t *cfn, const char *nm)
  274. {
  275.     tmpfs_node_t *parentp = TMPFS_NODE(pfn);
  276.     tmpfs_node_t *childp = TMPFS_NODE(cfn);
  277.     tmpfs_dentry_t *dentryp;
  278.     link_t *lnk;
  279.  
  280.     assert(parentp->type == TMPFS_DIRECTORY);
  281.  
  282.     /* Check for duplicit entries. */
  283.     for (lnk = parentp->cs_head.next; lnk != &parentp->cs_head;
  284.         lnk = lnk->next) {
  285.         dentryp = list_get_instance(lnk, tmpfs_dentry_t, link);
  286.         if (!str_cmp(dentryp->name, nm))
  287.             return EEXIST;
  288.     }
  289.  
  290.     /* Allocate and initialize the dentry. */
  291.     dentryp = malloc(sizeof(tmpfs_dentry_t));
  292.     if (!dentryp)
  293.         return ENOMEM;
  294.     tmpfs_dentry_initialize(dentryp);
  295.  
  296.     /* Populate and link the new dentry. */
  297.     size_t size = str_size(nm);
  298.     dentryp->name = malloc(size + 1);
  299.     if (!dentryp->name) {
  300.         free(dentryp);
  301.         return ENOMEM;
  302.     }
  303.     str_cpy(dentryp->name, size + 1, nm);
  304.     dentryp->node = childp;
  305.     childp->lnkcnt++;
  306.     list_append(&dentryp->link, &parentp->cs_head);
  307.  
  308.     return EOK;
  309. }
  310.  
  311. int tmpfs_unlink_node(fs_node_t *pfn, fs_node_t *cfn, const char *nm)
  312. {
  313.     tmpfs_node_t *parentp = TMPFS_NODE(pfn);
  314.     tmpfs_node_t *childp = NULL;
  315.     tmpfs_dentry_t *dentryp;
  316.     link_t *lnk;
  317.  
  318.     if (!parentp)
  319.         return EBUSY;
  320.    
  321.     for (lnk = parentp->cs_head.next; lnk != &parentp->cs_head;
  322.         lnk = lnk->next) {
  323.         dentryp = list_get_instance(lnk, tmpfs_dentry_t, link);
  324.         if (!str_cmp(dentryp->name, nm)) {
  325.             childp = dentryp->node;
  326.             assert(FS_NODE(childp) == cfn);
  327.             break;
  328.         }  
  329.     }
  330.  
  331.     if (!childp)
  332.         return ENOENT;
  333.        
  334.     if ((childp->lnkcnt == 1) && !list_empty(&childp->cs_head))
  335.         return ENOTEMPTY;
  336.  
  337.     list_remove(&dentryp->link);
  338.     free(dentryp);
  339.     childp->lnkcnt--;
  340.  
  341.     return EOK;
  342. }
  343.  
  344. int tmpfs_destroy_node(fs_node_t *fn)
  345. {
  346.     tmpfs_node_t *nodep = TMPFS_NODE(fn);
  347.    
  348.     assert(!nodep->lnkcnt);
  349.     assert(list_empty(&nodep->cs_head));
  350.  
  351.     unsigned long key[] = {
  352.         [NODES_KEY_INDEX] = nodep->index,
  353.         [NODES_KEY_DEV] = nodep->dev_handle
  354.     };
  355.     hash_table_remove(&nodes, key, 2);
  356.  
  357.     if (nodep->type == TMPFS_FILE)
  358.         free(nodep->data);
  359.     free(nodep->bp);
  360.     free(nodep);
  361.     return EOK;
  362. }
  363.  
  364. void tmpfs_mounted(ipc_callid_t rid, ipc_call_t *request)
  365. {
  366.     dev_handle_t dev_handle = (dev_handle_t) IPC_GET_ARG1(*request);
  367.  
  368.     /* accept the mount options */
  369.     ipc_callid_t callid;
  370.     size_t size;
  371.     if (!ipc_data_write_receive(&callid, &size)) {
  372.         ipc_answer_0(callid, EINVAL);
  373.         ipc_answer_0(rid, EINVAL);
  374.         return;
  375.     }
  376.     char *opts = malloc(size + 1);
  377.     if (!opts) {
  378.         ipc_answer_0(callid, ENOMEM);
  379.         ipc_answer_0(rid, ENOMEM);
  380.         return;
  381.     }
  382.     ipcarg_t retval = ipc_data_write_finalize(callid, opts, size);
  383.     if (retval != EOK) {
  384.         ipc_answer_0(rid, retval);
  385.         free(opts);
  386.         return;
  387.     }
  388.     opts[size] = '\0';
  389.  
  390.     /* Initialize TMPFS instance. */
  391.     if (!tmpfs_instance_init(dev_handle)) {
  392.         ipc_answer_0(rid, ENOMEM);
  393.         return;
  394.     }
  395.  
  396.     tmpfs_node_t *rootp = TMPFS_NODE(tmpfs_root_get(dev_handle));
  397.     if (str_cmp(opts, "restore") == 0) {
  398.         if (tmpfs_restore(dev_handle))
  399.             ipc_answer_3(rid, EOK, rootp->index, rootp->size,
  400.                 rootp->lnkcnt);
  401.         else
  402.             ipc_answer_0(rid, ELIMIT);
  403.     } else {
  404.         ipc_answer_3(rid, EOK, rootp->index, rootp->size,
  405.             rootp->lnkcnt);
  406.     }
  407. }
  408.  
  409. void tmpfs_mount(ipc_callid_t rid, ipc_call_t *request)
  410. {
  411.     dev_handle_t mp_dev_handle = (dev_handle_t) IPC_GET_ARG1(*request);
  412.     fs_index_t mp_index = (fs_index_t) IPC_GET_ARG2(*request);
  413.     fs_handle_t mr_fs_handle = (fs_handle_t) IPC_GET_ARG3(*request);
  414.     dev_handle_t mr_dev_handle = (dev_handle_t) IPC_GET_ARG4(*request);
  415.    
  416.     ipc_answer_0(rid, ENOTSUP);
  417. }
  418.  
  419. void tmpfs_lookup(ipc_callid_t rid, ipc_call_t *request)
  420. {
  421.     libfs_lookup(&tmpfs_libfs_ops, tmpfs_reg.fs_handle, rid, request);
  422. }
  423.  
  424. void tmpfs_read(ipc_callid_t rid, ipc_call_t *request)
  425. {
  426.     dev_handle_t dev_handle = (dev_handle_t)IPC_GET_ARG1(*request);
  427.     fs_index_t index = (fs_index_t)IPC_GET_ARG2(*request);
  428.     off_t pos = (off_t)IPC_GET_ARG3(*request);
  429.  
  430.     /*
  431.      * Lookup the respective TMPFS node.
  432.      */
  433.     link_t *hlp;
  434.     unsigned long key[] = {
  435.         [NODES_KEY_INDEX] = index,
  436.         [NODES_KEY_DEV] = dev_handle,
  437.     };
  438.     hlp = hash_table_find(&nodes, key);
  439.     if (!hlp) {
  440.         ipc_answer_0(rid, ENOENT);
  441.         return;
  442.     }
  443.     tmpfs_node_t *nodep = hash_table_get_instance(hlp, tmpfs_node_t,
  444.         nh_link);
  445.  
  446.     /*
  447.      * Receive the read request.
  448.      */
  449.     ipc_callid_t callid;
  450.     size_t size;
  451.     if (!ipc_data_read_receive(&callid, &size)) {
  452.         ipc_answer_0(callid, EINVAL);  
  453.         ipc_answer_0(rid, EINVAL);
  454.         return;
  455.     }
  456.  
  457.     size_t bytes;
  458.     if (nodep->type == TMPFS_FILE) {
  459.         bytes = max(0, min(nodep->size - pos, size));
  460.         (void) ipc_data_read_finalize(callid, nodep->data + pos,
  461.             bytes);
  462.     } else {
  463.         tmpfs_dentry_t *dentryp;
  464.         link_t *lnk;
  465.         int i;
  466.        
  467.         assert(nodep->type == TMPFS_DIRECTORY);
  468.        
  469.         /*
  470.          * Yes, we really use O(n) algorithm here.
  471.          * If it bothers someone, it could be fixed by introducing a
  472.          * hash table.
  473.          */
  474.         for (i = 0, lnk = nodep->cs_head.next;
  475.             i < pos && lnk != &nodep->cs_head;
  476.             i++, lnk = lnk->next)
  477.             ;
  478.  
  479.         if (lnk == &nodep->cs_head) {
  480.             ipc_answer_0(callid, ENOENT);
  481.             ipc_answer_1(rid, ENOENT, 0);
  482.             return;
  483.         }
  484.  
  485.         dentryp = list_get_instance(lnk, tmpfs_dentry_t, link);
  486.  
  487.         (void) ipc_data_read_finalize(callid, dentryp->name,
  488.             str_size(dentryp->name) + 1);
  489.         bytes = 1;
  490.     }
  491.  
  492.     /*
  493.      * Answer the VFS_READ call.
  494.      */
  495.     ipc_answer_1(rid, EOK, bytes);
  496. }
  497.  
  498. void tmpfs_write(ipc_callid_t rid, ipc_call_t *request)
  499. {
  500.     dev_handle_t dev_handle = (dev_handle_t)IPC_GET_ARG1(*request);
  501.     fs_index_t index = (fs_index_t)IPC_GET_ARG2(*request);
  502.     off_t pos = (off_t)IPC_GET_ARG3(*request);
  503.  
  504.     /*
  505.      * Lookup the respective TMPFS node.
  506.      */
  507.     link_t *hlp;
  508.     unsigned long key[] = {
  509.         [NODES_KEY_INDEX] = index,
  510.         [NODES_KEY_DEV] = dev_handle
  511.     };
  512.     hlp = hash_table_find(&nodes, key);
  513.     if (!hlp) {
  514.         ipc_answer_0(rid, ENOENT);
  515.         return;
  516.     }
  517.     tmpfs_node_t *nodep = hash_table_get_instance(hlp, tmpfs_node_t,
  518.         nh_link);
  519.  
  520.     /*
  521.      * Receive the write request.
  522.      */
  523.     ipc_callid_t callid;
  524.     size_t size;
  525.     if (!ipc_data_write_receive(&callid, &size)) {
  526.         ipc_answer_0(callid, EINVAL);  
  527.         ipc_answer_0(rid, EINVAL);
  528.         return;
  529.     }
  530.  
  531.     /*
  532.      * Check whether the file needs to grow.
  533.      */
  534.     if (pos + size <= nodep->size) {
  535.         /* The file size is not changing. */
  536.         (void) ipc_data_write_finalize(callid, nodep->data + pos, size);
  537.         ipc_answer_2(rid, EOK, size, nodep->size);
  538.         return;
  539.     }
  540.     size_t delta = (pos + size) - nodep->size;
  541.     /*
  542.      * At this point, we are deliberately extremely straightforward and
  543.      * simply realloc the contents of the file on every write that grows the
  544.      * file. In the end, the situation might not be as bad as it may look:
  545.      * our heap allocator can save us and just grow the block whenever
  546.      * possible.
  547.      */
  548.     void *newdata = realloc(nodep->data, nodep->size + delta);
  549.     if (!newdata) {
  550.         ipc_answer_0(callid, ENOMEM);
  551.         ipc_answer_2(rid, EOK, 0, nodep->size);
  552.         return;
  553.     }
  554.     /* Clear any newly allocated memory in order to emulate gaps. */
  555.     memset(newdata + nodep->size, 0, delta);
  556.     nodep->size += delta;
  557.     nodep->data = newdata;
  558.     (void) ipc_data_write_finalize(callid, nodep->data + pos, size);
  559.     ipc_answer_2(rid, EOK, size, nodep->size);
  560. }
  561.  
  562. void tmpfs_truncate(ipc_callid_t rid, ipc_call_t *request)
  563. {
  564.     dev_handle_t dev_handle = (dev_handle_t)IPC_GET_ARG1(*request);
  565.     fs_index_t index = (fs_index_t)IPC_GET_ARG2(*request);
  566.     size_t size = (off_t)IPC_GET_ARG3(*request);
  567.  
  568.     /*
  569.      * Lookup the respective TMPFS node.
  570.      */
  571.     link_t *hlp;
  572.     unsigned long key[] = {
  573.         [NODES_KEY_INDEX] = index,
  574.         [NODES_KEY_DEV] = dev_handle
  575.     };
  576.     hlp = hash_table_find(&nodes, key);
  577.     if (!hlp) {
  578.         ipc_answer_0(rid, ENOENT);
  579.         return;
  580.     }
  581.     tmpfs_node_t *nodep = hash_table_get_instance(hlp, tmpfs_node_t,
  582.         nh_link);
  583.  
  584.     if (size == nodep->size) {
  585.         ipc_answer_0(rid, EOK);
  586.         return;
  587.     }
  588.  
  589.     void *newdata = realloc(nodep->data, size);
  590.     if (!newdata) {
  591.         ipc_answer_0(rid, ENOMEM);
  592.         return;
  593.     }
  594.     if (size > nodep->size) {
  595.         size_t delta = size - nodep->size;
  596.         memset(newdata + nodep->size, 0, delta);
  597.     }
  598.     nodep->size = size;
  599.     nodep->data = newdata;
  600.     ipc_answer_0(rid, EOK);
  601. }
  602.  
  603. void tmpfs_destroy(ipc_callid_t rid, ipc_call_t *request)
  604. {
  605.     dev_handle_t dev_handle = (dev_handle_t)IPC_GET_ARG1(*request);
  606.     fs_index_t index = (fs_index_t)IPC_GET_ARG2(*request);
  607.     int rc;
  608.  
  609.     link_t *hlp;
  610.     unsigned long key[] = {
  611.         [NODES_KEY_INDEX] = index,
  612.         [NODES_KEY_DEV] = dev_handle
  613.     };
  614.     hlp = hash_table_find(&nodes, key);
  615.     if (!hlp) {
  616.         ipc_answer_0(rid, ENOENT);
  617.         return;
  618.     }
  619.     tmpfs_node_t *nodep = hash_table_get_instance(hlp, tmpfs_node_t,
  620.         nh_link);
  621.     rc = tmpfs_destroy_node(FS_NODE(nodep));
  622.     ipc_answer_0(rid, rc);
  623. }
  624.  
  625. /**
  626.  * @}
  627.  */
  628.