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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:54:16 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:54:16 +0000
commit485f6ecd453d8a2fd8b9b9fadea03159d8b50797 (patch)
tree32451fa3cdd9321fb2591fada9891b2cb70a9cd1 /grub-core/kern/disk.c
parentInitial commit. (diff)
downloadgrub2-485f6ecd453d8a2fd8b9b9fadea03159d8b50797.tar.xz
grub2-485f6ecd453d8a2fd8b9b9fadea03159d8b50797.zip
Adding upstream version 2.06.upstream/2.06upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'grub-core/kern/disk.c')
-rw-r--r--grub-core/kern/disk.c544
1 files changed, 544 insertions, 0 deletions
diff --git a/grub-core/kern/disk.c b/grub-core/kern/disk.c
new file mode 100644
index 0000000..e1b0e07
--- /dev/null
+++ b/grub-core/kern/disk.c
@@ -0,0 +1,544 @@
+/*
+ * GRUB -- GRand Unified Bootloader
+ * Copyright (C) 2002,2003,2004,2006,2007,2008,2009,2010 Free Software Foundation, Inc.
+ *
+ * GRUB is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * GRUB is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GRUB. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <grub/disk.h>
+#include <grub/err.h>
+#include <grub/mm.h>
+#include <grub/types.h>
+#include <grub/partition.h>
+#include <grub/misc.h>
+#include <grub/time.h>
+#include <grub/file.h>
+#include <grub/i18n.h>
+
+#define GRUB_CACHE_TIMEOUT 2
+
+/* The last time the disk was used. */
+static grub_uint64_t grub_last_time = 0;
+
+struct grub_disk_cache grub_disk_cache_table[GRUB_DISK_CACHE_NUM];
+
+void (*grub_disk_firmware_fini) (void);
+int grub_disk_firmware_is_tainted;
+
+#if DISK_CACHE_STATS
+static unsigned long grub_disk_cache_hits;
+static unsigned long grub_disk_cache_misses;
+
+void
+grub_disk_cache_get_performance (unsigned long *hits, unsigned long *misses)
+{
+ *hits = grub_disk_cache_hits;
+ *misses = grub_disk_cache_misses;
+}
+#endif
+
+grub_err_t (*grub_disk_write_weak) (grub_disk_t disk,
+ grub_disk_addr_t sector,
+ grub_off_t offset,
+ grub_size_t size,
+ const void *buf);
+#include "disk_common.c"
+
+void
+grub_disk_cache_invalidate_all (void)
+{
+ unsigned i;
+
+ for (i = 0; i < GRUB_DISK_CACHE_NUM; i++)
+ {
+ struct grub_disk_cache *cache = grub_disk_cache_table + i;
+
+ if (cache->data && ! cache->lock)
+ {
+ grub_free (cache->data);
+ cache->data = 0;
+ }
+ }
+}
+
+static char *
+grub_disk_cache_fetch (unsigned long dev_id, unsigned long disk_id,
+ grub_disk_addr_t sector)
+{
+ struct grub_disk_cache *cache;
+ unsigned cache_index;
+
+ cache_index = grub_disk_cache_get_index (dev_id, disk_id, sector);
+ cache = grub_disk_cache_table + cache_index;
+
+ if (cache->dev_id == dev_id && cache->disk_id == disk_id
+ && cache->sector == sector)
+ {
+ cache->lock = 1;
+#if DISK_CACHE_STATS
+ grub_disk_cache_hits++;
+#endif
+ return cache->data;
+ }
+
+#if DISK_CACHE_STATS
+ grub_disk_cache_misses++;
+#endif
+
+ return 0;
+}
+
+static void
+grub_disk_cache_unlock (unsigned long dev_id, unsigned long disk_id,
+ grub_disk_addr_t sector)
+{
+ struct grub_disk_cache *cache;
+ unsigned cache_index;
+
+ cache_index = grub_disk_cache_get_index (dev_id, disk_id, sector);
+ cache = grub_disk_cache_table + cache_index;
+
+ if (cache->dev_id == dev_id && cache->disk_id == disk_id
+ && cache->sector == sector)
+ cache->lock = 0;
+}
+
+static grub_err_t
+grub_disk_cache_store (unsigned long dev_id, unsigned long disk_id,
+ grub_disk_addr_t sector, const char *data)
+{
+ unsigned cache_index;
+ struct grub_disk_cache *cache;
+
+ cache_index = grub_disk_cache_get_index (dev_id, disk_id, sector);
+ cache = grub_disk_cache_table + cache_index;
+
+ cache->lock = 1;
+ grub_free (cache->data);
+ cache->data = 0;
+ cache->lock = 0;
+
+ cache->data = grub_malloc (GRUB_DISK_SECTOR_SIZE << GRUB_DISK_CACHE_BITS);
+ if (! cache->data)
+ return grub_errno;
+
+ grub_memcpy (cache->data, data,
+ GRUB_DISK_SECTOR_SIZE << GRUB_DISK_CACHE_BITS);
+ cache->dev_id = dev_id;
+ cache->disk_id = disk_id;
+ cache->sector = sector;
+
+ return GRUB_ERR_NONE;
+}
+
+
+
+grub_disk_dev_t grub_disk_dev_list;
+
+void
+grub_disk_dev_register (grub_disk_dev_t dev)
+{
+ dev->next = grub_disk_dev_list;
+ grub_disk_dev_list = dev;
+}
+
+void
+grub_disk_dev_unregister (grub_disk_dev_t dev)
+{
+ grub_disk_dev_t *p, q;
+
+ for (p = &grub_disk_dev_list, q = *p; q; p = &(q->next), q = q->next)
+ if (q == dev)
+ {
+ *p = q->next;
+ break;
+ }
+}
+
+/* Return the location of the first ',', if any, which is not
+ escaped by a '\'. */
+static const char *
+find_part_sep (const char *name)
+{
+ const char *p = name;
+ char c;
+
+ while ((c = *p++) != '\0')
+ {
+ if (c == '\\' && *p == ',')
+ p++;
+ else if (c == ',')
+ return p - 1;
+ }
+ return NULL;
+}
+
+grub_disk_t
+grub_disk_open (const char *name)
+{
+ const char *p;
+ grub_disk_t disk;
+ grub_disk_dev_t dev;
+ char *raw = (char *) name;
+ grub_uint64_t current_time;
+
+ grub_dprintf ("disk", "Opening `%s'...\n", name);
+
+ disk = (grub_disk_t) grub_zalloc (sizeof (*disk));
+ if (! disk)
+ return 0;
+ disk->log_sector_size = GRUB_DISK_SECTOR_BITS;
+ /* Default 1MiB of maximum agglomerate. */
+ disk->max_agglomerate = 1048576 >> (GRUB_DISK_SECTOR_BITS
+ + GRUB_DISK_CACHE_BITS);
+
+ p = find_part_sep (name);
+ if (p)
+ {
+ grub_size_t len = p - name;
+
+ raw = grub_malloc (len + 1);
+ if (! raw)
+ goto fail;
+
+ grub_memcpy (raw, name, len);
+ raw[len] = '\0';
+ disk->name = grub_strdup (raw);
+ }
+ else
+ disk->name = grub_strdup (name);
+ if (! disk->name)
+ goto fail;
+
+ for (dev = grub_disk_dev_list; dev; dev = dev->next)
+ {
+ if ((dev->disk_open) (raw, disk) == GRUB_ERR_NONE)
+ break;
+ else if (grub_errno == GRUB_ERR_UNKNOWN_DEVICE)
+ grub_errno = GRUB_ERR_NONE;
+ else
+ goto fail;
+ }
+
+ if (! dev)
+ {
+ grub_error (GRUB_ERR_UNKNOWN_DEVICE, N_("disk `%s' not found"),
+ name);
+ goto fail;
+ }
+ if (disk->log_sector_size > GRUB_DISK_CACHE_BITS + GRUB_DISK_SECTOR_BITS
+ || disk->log_sector_size < GRUB_DISK_SECTOR_BITS)
+ {
+ grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET,
+ "sector sizes of %d bytes aren't supported yet",
+ (1 << disk->log_sector_size));
+ goto fail;
+ }
+
+ disk->dev = dev;
+
+ if (p)
+ {
+ disk->partition = grub_partition_probe (disk, p + 1);
+ if (! disk->partition)
+ {
+ /* TRANSLATORS: It means that the specified partition e.g.
+ hd0,msdos1=/dev/sda1 doesn't exist. */
+ grub_error (GRUB_ERR_UNKNOWN_DEVICE, N_("no such partition"));
+ goto fail;
+ }
+ }
+
+ /* The cache will be invalidated about 2 seconds after a device was
+ closed. */
+ current_time = grub_get_time_ms ();
+
+ if (current_time > (grub_last_time
+ + GRUB_CACHE_TIMEOUT * 1000))
+ grub_disk_cache_invalidate_all ();
+
+ grub_last_time = current_time;
+
+ fail:
+
+ if (raw && raw != name)
+ grub_free (raw);
+
+ if (grub_errno != GRUB_ERR_NONE)
+ {
+ grub_error_push ();
+ grub_dprintf ("disk", "Opening `%s' failed.\n", name);
+ grub_error_pop ();
+
+ grub_disk_close (disk);
+ return 0;
+ }
+
+ return disk;
+}
+
+void
+grub_disk_close (grub_disk_t disk)
+{
+ grub_partition_t part;
+ grub_dprintf ("disk", "Closing `%s'.\n", disk->name);
+
+ if (disk->dev && disk->dev->disk_close)
+ (disk->dev->disk_close) (disk);
+
+ /* Reset the timer. */
+ grub_last_time = grub_get_time_ms ();
+
+ while (disk->partition)
+ {
+ part = disk->partition->parent;
+ grub_free (disk->partition);
+ disk->partition = part;
+ }
+ grub_free ((void *) disk->name);
+ grub_free (disk);
+}
+
+/* Small read (less than cache size and not pass across cache unit boundaries).
+ sector is already adjusted and is divisible by cache unit size.
+ */
+static grub_err_t
+grub_disk_read_small_real (grub_disk_t disk, grub_disk_addr_t sector,
+ grub_off_t offset, grub_size_t size, void *buf)
+{
+ char *data;
+ char *tmp_buf;
+
+ /* Fetch the cache. */
+ data = grub_disk_cache_fetch (disk->dev->id, disk->id, sector);
+ if (data)
+ {
+ /* Just copy it! */
+ grub_memcpy (buf, data + offset, size);
+ grub_disk_cache_unlock (disk->dev->id, disk->id, sector);
+ return GRUB_ERR_NONE;
+ }
+
+ /* Allocate a temporary buffer. */
+ tmp_buf = grub_malloc (GRUB_DISK_SECTOR_SIZE << GRUB_DISK_CACHE_BITS);
+ if (! tmp_buf)
+ return grub_errno;
+
+ /* Otherwise read data from the disk actually. */
+ if (disk->total_sectors == GRUB_DISK_SIZE_UNKNOWN
+ || sector + GRUB_DISK_CACHE_SIZE
+ < (disk->total_sectors << (disk->log_sector_size - GRUB_DISK_SECTOR_BITS)))
+ {
+ grub_err_t err;
+ err = (disk->dev->disk_read) (disk, transform_sector (disk, sector),
+ 1U << (GRUB_DISK_CACHE_BITS
+ + GRUB_DISK_SECTOR_BITS
+ - disk->log_sector_size), tmp_buf);
+ if (!err)
+ {
+ /* Copy it and store it in the disk cache. */
+ grub_memcpy (buf, tmp_buf + offset, size);
+ grub_disk_cache_store (disk->dev->id, disk->id,
+ sector, tmp_buf);
+ grub_free (tmp_buf);
+ return GRUB_ERR_NONE;
+ }
+ }
+
+ grub_free (tmp_buf);
+ grub_errno = GRUB_ERR_NONE;
+
+ {
+ /* Uggh... Failed. Instead, just read necessary data. */
+ unsigned num;
+ grub_disk_addr_t aligned_sector;
+
+ sector += (offset >> GRUB_DISK_SECTOR_BITS);
+ offset &= ((1 << GRUB_DISK_SECTOR_BITS) - 1);
+ aligned_sector = (sector & ~((1ULL << (disk->log_sector_size
+ - GRUB_DISK_SECTOR_BITS))
+ - 1));
+ offset += ((sector - aligned_sector) << GRUB_DISK_SECTOR_BITS);
+ num = ((size + offset + (1ULL << (disk->log_sector_size))
+ - 1) >> (disk->log_sector_size));
+
+ tmp_buf = grub_malloc (num << disk->log_sector_size);
+ if (!tmp_buf)
+ return grub_errno;
+
+ if ((disk->dev->disk_read) (disk, transform_sector (disk, aligned_sector),
+ num, tmp_buf))
+ {
+ grub_error_push ();
+ grub_dprintf ("disk", "%s read failed\n", disk->name);
+ grub_error_pop ();
+ grub_free (tmp_buf);
+ return grub_errno;
+ }
+ grub_memcpy (buf, tmp_buf + offset, size);
+ grub_free (tmp_buf);
+ return GRUB_ERR_NONE;
+ }
+}
+
+static grub_err_t
+grub_disk_read_small (grub_disk_t disk, grub_disk_addr_t sector,
+ grub_off_t offset, grub_size_t size, void *buf)
+{
+ grub_err_t err;
+
+ err = grub_disk_read_small_real (disk, sector, offset, size, buf);
+ if (err)
+ return err;
+ if (disk->read_hook)
+ (disk->read_hook) (sector + (offset >> GRUB_DISK_SECTOR_BITS),
+ offset & (GRUB_DISK_SECTOR_SIZE - 1),
+ size, disk->read_hook_data);
+ return GRUB_ERR_NONE;
+}
+
+/* Read data from the disk. */
+grub_err_t
+grub_disk_read (grub_disk_t disk, grub_disk_addr_t sector,
+ grub_off_t offset, grub_size_t size, void *buf)
+{
+ /* First of all, check if the region is within the disk. */
+ if (grub_disk_adjust_range (disk, &sector, &offset, size) != GRUB_ERR_NONE)
+ {
+ grub_error_push ();
+ grub_dprintf ("disk", "Read out of range: sector 0x%llx (%s).\n",
+ (unsigned long long) sector, grub_errmsg);
+ grub_error_pop ();
+ return grub_errno;
+ }
+
+ /* First read until first cache boundary. */
+ if (offset || (sector & (GRUB_DISK_CACHE_SIZE - 1)))
+ {
+ grub_disk_addr_t start_sector;
+ grub_size_t pos;
+ grub_err_t err;
+ grub_size_t len;
+
+ start_sector = sector & ~((grub_disk_addr_t) GRUB_DISK_CACHE_SIZE - 1);
+ pos = (sector - start_sector) << GRUB_DISK_SECTOR_BITS;
+ len = ((GRUB_DISK_SECTOR_SIZE << GRUB_DISK_CACHE_BITS)
+ - pos - offset);
+ if (len > size)
+ len = size;
+ err = grub_disk_read_small (disk, start_sector,
+ offset + pos, len, buf);
+ if (err)
+ return err;
+ buf = (char *) buf + len;
+ size -= len;
+ offset += len;
+ sector += (offset >> GRUB_DISK_SECTOR_BITS);
+ offset &= ((1 << GRUB_DISK_SECTOR_BITS) - 1);
+ }
+
+ /* Until SIZE is zero... */
+ while (size >= (GRUB_DISK_CACHE_SIZE << GRUB_DISK_SECTOR_BITS))
+ {
+ char *data = NULL;
+ grub_disk_addr_t agglomerate;
+ grub_err_t err;
+
+ /* agglomerate read until we find a first cached entry. */
+ for (agglomerate = 0; agglomerate
+ < (size >> (GRUB_DISK_SECTOR_BITS + GRUB_DISK_CACHE_BITS))
+ && agglomerate < disk->max_agglomerate;
+ agglomerate++)
+ {
+ data = grub_disk_cache_fetch (disk->dev->id, disk->id,
+ sector + (agglomerate
+ << GRUB_DISK_CACHE_BITS));
+ if (data)
+ break;
+ }
+
+ if (data)
+ {
+ grub_memcpy ((char *) buf
+ + (agglomerate << (GRUB_DISK_CACHE_BITS
+ + GRUB_DISK_SECTOR_BITS)),
+ data, GRUB_DISK_CACHE_SIZE << GRUB_DISK_SECTOR_BITS);
+ grub_disk_cache_unlock (disk->dev->id, disk->id,
+ sector + (agglomerate
+ << GRUB_DISK_CACHE_BITS));
+ }
+
+ if (agglomerate)
+ {
+ grub_disk_addr_t i;
+
+ err = (disk->dev->disk_read) (disk, transform_sector (disk, sector),
+ agglomerate << (GRUB_DISK_CACHE_BITS
+ + GRUB_DISK_SECTOR_BITS
+ - disk->log_sector_size),
+ buf);
+ if (err)
+ return err;
+
+ for (i = 0; i < agglomerate; i ++)
+ grub_disk_cache_store (disk->dev->id, disk->id,
+ sector + (i << GRUB_DISK_CACHE_BITS),
+ (char *) buf
+ + (i << (GRUB_DISK_CACHE_BITS
+ + GRUB_DISK_SECTOR_BITS)));
+
+
+ if (disk->read_hook)
+ (disk->read_hook) (sector, 0, agglomerate << (GRUB_DISK_CACHE_BITS + GRUB_DISK_SECTOR_BITS),
+ disk->read_hook_data);
+
+ sector += agglomerate << GRUB_DISK_CACHE_BITS;
+ size -= agglomerate << (GRUB_DISK_CACHE_BITS + GRUB_DISK_SECTOR_BITS);
+ buf = (char *) buf
+ + (agglomerate << (GRUB_DISK_CACHE_BITS + GRUB_DISK_SECTOR_BITS));
+ }
+
+ if (data)
+ {
+ if (disk->read_hook)
+ (disk->read_hook) (sector, 0, (GRUB_DISK_CACHE_SIZE << GRUB_DISK_SECTOR_BITS),
+ disk->read_hook_data);
+ sector += GRUB_DISK_CACHE_SIZE;
+ buf = (char *) buf + (GRUB_DISK_CACHE_SIZE << GRUB_DISK_SECTOR_BITS);
+ size -= (GRUB_DISK_CACHE_SIZE << GRUB_DISK_SECTOR_BITS);
+ }
+ }
+
+ /* And now read the last part. */
+ if (size)
+ {
+ grub_err_t err;
+ err = grub_disk_read_small (disk, sector, 0, size, buf);
+ if (err)
+ return err;
+ }
+
+ return grub_errno;
+}
+
+grub_uint64_t
+grub_disk_native_sectors (grub_disk_t disk)
+{
+ if (disk->partition)
+ return grub_partition_get_len (disk->partition);
+ else if (disk->total_sectors != GRUB_DISK_SIZE_UNKNOWN)
+ return disk->total_sectors << (disk->log_sector_size - GRUB_DISK_SECTOR_BITS);
+ else
+ return GRUB_DISK_SIZE_UNKNOWN;
+}